Virtuoso's in-built virtual database engine for ODBC and JDBC accessible databases enables it to act as bridge between Entity Frameworks & ADO.NET based client applications. Thus, you simply link external databases into Virtuoso using the browser based Conductor UI or programmatically using SQL extensions. Once the external tables a linked/attached, they inherit the functionality prowess of Virtuoso, and this particular use case scenario, complete compatibility with Entity Frameworks and ADO.NET 3.5.

Specifies Virtuoso data types.

Table 7.1. 

Member name Description
Binary BINARY data. This maps to an Array of type Byte .
Char CHAR data. This maps to String .
Date DATE data. This maps to DateTime .
DateTime DATETIME data. This maps to DateTime .
Decimal This is equal to Numeric .
Double DOUBLE PRECISION data. This maps to Double .
Float This is equal to Double.
Integer INTEGER data. This maps to Int32
LongBinary LONG BINARY data. This maps to an Array of type Byte .
LongNVarChar LONG NVARCHAR data. This maps to String .
LongVarChar LONG VARCHAR data. This maps to String .
NChar NChar data. This maps to String .
Numeric NUMERIC data. This maps to Decimal
NVarChar NVARCHAR data. This maps to String .
Real REAL data, This maps to Single .
SmallInt SMALLINT data. This maps to Int16
Time TIME data. This maps to TimeSpan
TimeStamp TIMESTAMP data. This maps to an Array of type Byte .
VarBinary VARBINARY data. This maps to an Array of type Byte .
VarChar VARCHAR data. This maps to String .

Represents an SQL statement or stored procedure to execute against a Virtuoso database. This class cannot be inherited.

Figure 7.29. Virtuoso .Net Provider VirtuosoCommand Class

Virtuoso .Net Provider VirtuosoCommand Class

 
              public 
              sealed 
              class 
              VirtuosoCommand
             extends, 
              Component
            
implements, ICloneable , IDbCommand {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

The VirtuosoCommand class provides the following methods for executing commands against a Virtuoso database:

Table 7.2. 

Item Description
ExecuteReader Executes commands that return rows.
ExecuteNonQuery Executes commands such as SQL INSERT, DELETE, UPDATE, and SET statements.
ExecuteScalar Retrieves a single value (for example, an aggregate value) from a database.

Initializes a new instance of the VirtuosoCommand class.

Initializes a new instance of the VirtuosoCommand class.

public VirtuosoCommand();

The base constructor initializes all fields to their default values. The following table shows initial property values for an instance of VirtuosoCommand.

Table 7.3. 

Properties Initial Value
CommandText empty string ("")
CommandTimeout 30
CommandType CommandType.Text
Connection null

You can change the value for any of these properties through a separate call to the property.

Initializes a new instance of the VirtuosoCommand class with the text of the query.

public VirtuosoCommand( string  cmdText );
cmdText

The text of the query.

Initializes a new instance of the VirtuosoCommand class with the text of the query and an VirtuosoConnection object.

public VirtuosoCommand( string  cmdText ,
                        VirtuosoConnection  connection );
cmdText

The text of the query.

connection

A VirtuosoConnection object that represents the connection to a Virtuoso database.

The Virtuoso ADO.NET Provider ConnectionString property implements the IDbConnection.ConnectionString property to get or set the string used to open a Virtuoso database connection, and includes the source database name and other parameters needed to establish the initial connection. The default value is an empty string.

public  string  ConnectionString  ;

Includes the source database name and other parameters needed to establish the initial connection. The default value is an empty string.

ConnectionString has the following syntax: Each connection string is a sequence of settings Individual settings are separated by semicolons. Each setting is a pair of name and value delimited by the equal sign. Whitespace is ignored on either side of both names and values. Names are case insensitive. The value part can be quoted by either single or double quote characters or remain unquoted at all. However if it includes a semicolon, single quote, or double quote characters, it must be enclosed in either type of quotes. To embed the same character that is used for enclosing the value the character within the value must be doubled.

The following table lists the valid names for values within the ConnectionString:

Table 7.4. 

Name Default Description
Connect Timeout or Connection Timeout 15 The number of seconds to wait for a connection to the server before terminating the attempt and generating an error.
Connection Lifetime 0 When a connection is returned to the pool, its creation time is compared with the current time, and the connection is destroyed if that time span (in seconds) exceeds the value specified by connection lifetime. Useful in clustered configurations to force load balancing between a running server and a server just brought on-line.
Charset utf-16 Specifies the character set to be used by the provider when passing string values to and from the database. Must be set to utf-8 to handle Unicode strings passed in SPARQL/SPASQL queries of RDF data.
Data Source or Server or Address or Network Address or Host   The name or network address of the instance of Virtuoso server to which to connect. Can take comma delimited list of instances for connection fail over.
Encrypt false Specifies if the connection must be SSL encrypted. Currently encryption only works with an ODBC-based provider.
Enlist true When true, the pooler automatically enlists the connection in the creation thread's current transaction context.
Initial Catalog or Database   The name of the database.
Max Pool Size 100 The maximum number of connections allowed in the pool.
Min Pool Size 0 The minimum number of connections allowed in the pool.
Password or Pwd   The password for the Virtuoso account logging on.
Persist Security Info false When set to 'false', security-sensitive information, such as the password, is not returned as part of the connection if the connection is open or has ever been in an open State. Resetting the connection string resets all connection string values including the password.
Pooling true When true, the VirtuosoConnection object is drawn from the appropriate pool, or if necessary, is created and added to the appropriate pool.
RoundRobin false Enables load balancing in which case the server for the connection is chosen at random from the comma delimited provided as for a Failover connection.
User ID or Uid   The Virtuoso login name.

IDbCommand.ConnectionString

The ConnectionString is similar to an OLE DB connection string, but is not identical. Unlike OLE DB or ADO, the connection string that is returned is the same as the user set ConnectionString minus security information if the Persist Security Info value is set to false (default). The Virtuoso ADO.NET Data Provider neither persists nor returns the password in a connection string unless you set Persist Security Info to true.

The ConnectionString property can be set only when the connection is closed. Many of the connection string values have corresponding read-only properties. When the connection string is set, all of these properties are updated, except when an error is detected; in this case, none of the properties are updated. VirtuosoConnection properties return only those settings contained in the ConnectionString .

Resetting the ConnectionString on a closed connection resets all connection string values (and related properties) including the password. For example, if you set a connection string that includes "Database=Demo ", and then reset the connection string to "Data Source=myserver;User ID=dba;Password=dba ", the Database property is no longer set to Demo .

The connection string is parsed immediately after being set. If errors in syntax are found when parsing, a runtime exception (e.g., ArgumentException ) is generated. Other errors can be found only when an attempt is made to open the connection.

Initializes a new instance of the VirtuosoCommand class with the text of the query, an VirtuosoConnection object, and the VirtuosoTransaction.

public VirtuosoCommand( string  cmdText ,
                        VirtuosoConnection  connection ,
                        VirtuosoTransaction  transaction );
cmdText

The text of the query.

connection

A VirtuosoConnection object that represents the connection to a Virtuoso database.

transaction

The VirtuosoTransaction in which the VirtuosoCommand executes.

Gets or sets the SQL statement or stored procedure to execute against the Virtuoso database.

public  string  CommandText  ;

The SQL statement or stored procedure to execute. The default value is an empty string ("").

IDbCommand.CommandText

When the CommandType property is set to StoredProcedure, the CommandText property should be set using standard ODBC stored procedure escape sequences. Setting the CommandText to the name of the stored procedure does not function as it does for some other .NET data providers.

The Virtuoso .NET Data Provider does not support named parameters for passing parameters to a SQL statement or a stored procedure called by an OleDbCommand when CommandType is set to Text. In this case, the question mark (?) placeholder must be used. For example:

SELECT * FROM Customers WHERE CustomerID = ?

As a result, the order in which VirtuosoParameter objects are added to the VirtuosoParameterCollection must directly correspond to the position of the question mark placeholder for the parameter.

Gets or sets the wait time before terminating an attempt to execute a command and generating an error.

public  int  CommandTimeout  ;

The time (in seconds) to wait for the command to execute. The default is 30 seconds.

IDbCommand.CommandTimeout

A value of zero (0) specifies no limit to the wait time, rather than no wait time, and therefore should be avoided.

Gets or sets a value indicating how the CommandText property is interpreted.

public  CommandType  CommandType  ;

One of the System.Data.CommandType values. The default is Text.

IDbCommand.CommandType

When the CommandType property is set to StoredProcedure, you should set the CommandText property to the full ODBC call syntax. The command then executes this stored procedure when you call one of the Execute methods (for example, ExecuteReader or ExecuteNonQuery).

The Connection, CommandType and CommandText properties cannot be set if the current connection is performing an execute or fetch operation.

The Virtuoso .NET Data Provider does not support passing named parameters to an SQL statement or to a stored procedure called by a VirtuosoCommand. In either of these cases, use the question mark (?) placeholder. For example:

SELECT * FROM Customers WHERE CustomerID = ?

The order in which VirtuosoParameter objects are added to the VirtuosoParameterCollection must directly correspond to the position of the question mark placeholder for the parameter.

Gets or sets the VirtuosoConnection used by this instance of the VirtuosoCommand.

public  VirtuosoConnection  Connection  ;

The connection to a Virtuoso database. The default is a null value.

Gets the VirtuosoParameterCollection.

public  VirtuosoParameterCollection  Connection  ;

The parameters of the SQL statement or stored procedure. The default is an empty collection.

When CommandType is set to Text, the Virtuoso .NET Data Provider does not support passing named parameters to an SQL statement or to a stored procedure called by an VirtuosoCommand. In either of these cases, use the question mark (?) placeholder. For example:

SELECT * FROM Customers WHERE CustomerID = ?

The order in which VirtuosoParameter objects are added to the VirtuosoParameterCollection must directly correspond to the position of the question mark placeholder for the parameter in the command text.

[Note] Note:

If the parameters in the collection do not match the requirements of the query to be executed, an error may result.

Gets or sets the VirtuosoTransaction within which the VirtuosoCommand executes.

public  VirtuosoTransaction  Transaction  ;

A VirtuosoTransaction. The default is a null value.

You cannot set the Transaction property if it is already set to a specific value, and the command is in the process of executing. If you set the transaction property to an VirtuosoTransaction object that is not connected to the same VirtuosoConnection as the VirtuosoCommand object, an exception will be thrown the next time you attempt to execute a statement.

Gets or sets how command results are applied to the DataRow when used by the Update method of the DbDataAdapter.

public  UpdateRowSource  UpdatedRowSource  ;

One of the System.Data.UpdateRowSource values.

IDbCommand.UpdatedRowSource

Attempts to cancel the execution of an VirtuosoCommand.

public void Cancel();

IDbCommand.Cancel

If there is nothing to cancel, nothing happens. However, if there is a command in process, and the attempt to cancel fails, no exception is generated.

Creates a new instance of a VirtuosoParameter object.

public VirtuosoParameter CreateParameter();

A VirtuosoParameter object.

The CreateParameter method is a strongly-typed version of IDbCommand.CreateParameter.

Executes an SQL statement against the Connection and returns the number of rows affected.

public int ExecuteNonQuery();

For UPDATE, INSERT, and DELETE statements, the return value is the number of rows affected by the command. For all other types of statements, the return value is -1.

IDbCommand.ExecuteNonQuery

You can use ExecuteNonQuery to perform catalog operations (for example, querying the structure of a database or creating database objects such as tables); or to change the data in a database, without using a DataSet, by executing UPDATE, INSERT, or DELETE statements.

Although ExecuteNonQuery does not return any rows, any output parameters or return values mapped to parameters are populated with data.

Sends the CommandText to the Connection and builds a VirtuosoDataReader.

Sends the CommandText to the Connection and builds a VirtuosoDataReader.

public VirtuosoDataReader ExecuteReader();

A VirtuosoDataReader object.

Sends the CommandText to the Connection and builds a VirtuosoDataReader using one of the CommandBehavior values.

public VirtuosoDataReader ExecuteReader( CommandBehavior  behavior );
behavior

One of the System.Data.CommandBehavior values.

A VirtuosoDataReader object.

Executes the query, and returns the first column of the first row in the resultset returned by the query. Extra columns or rows are ignored.

public object ExecuteScalar();

The first column of the first row in the resultset.

IDbCommand.ExecuteScalar

Use the ExecuteScalar method to retrieve a single value (for example, an aggregate value) from a database. This requires less code than using the ExecuteReader method, and then performing the operations necessary to generate the single value using the data returned by a VirtuosoDataReader.

A typical ExecuteScalar query can be formatted as in the following C# example:

command.CommandText = "select count(*) from foobar";
int count = (int) command.ExecuteScalar();

This member supports the .NET Framework infrastructure and is not intended to be used directly from your code.

object ICloneable.Clone();

This member supports the .NET Framework infrastructure and is not intended to be used directly from your code.

IDbDataParameter IDbCommand.CreateParameter();

This member supports the .NET Framework infrastructure and is not intended to be used directly from your code.

This member supports the .NET Framework infrastructure and is not intended to be used directly from your code.

IDataReader IDbCommand.ExecuteReader();

This member supports the .NET Framework infrastructure and is not intended to be used directly from your code.

IDataReader IDbCommand.ExecuteReader( CommandBehavior  behavior );

Creates a prepared (or compiled) version of the command at the Virtuoso server.

public void Prepare();

IDbCommand.Prepare

Provides a means of automatically generating single-table commands used to reconcile changes made to a DataSet with the associated Virtuoso database. This class cannot be inherited.

System.Object
System.MarshalByRefObject
System.ComponentModel.Component
VirtuosoCommandBuilder
 
              public 
              sealed 
              class 
              VirtuosoCommandBuilder
             extends, 
              Component
             {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

The VirtuosoDataAdapter does not automatically generate the SQL statements required to reconcile changes made to a DataSet associated with the data source. However, you can create a VirtuosoCommandBuilder object that generates SQL statements for single-table updates if you set the SelectCommand property of the VirtuosoDataAdapter. Then, the VirtuosoCommandBuilder generates any additional SQL statements that you do not set.

The relationship between a VirtuosoDataAdapter and its corresponding VirtuosoCommandBuilder is always one-to-one. To create this correspondence, you set the DataAdapter property of the VirtuosoCommandBuilder object. This causes the VirtuosoCommandBuilder to register itself as a listener for RowUpdating events on the specified VirtuosoDataAdapter object.

To generate INSERT, UPDATE, or DELETE statements, the VirtuosoCommandBuilder uses the SelectCommand property to retrieve a required set of metadata. If you change the value of SelectCommand after the metadata has been retrieved (for example, after the first update), you then should call the RefreshSchema method to update the metadata.

The VirtuosoCommandBuilder also uses the Connection, CommandTimeout, and Transaction properties referenced by the SelectCommand. The user should call RefreshSchema if any of these properties are modified, or if the value of the SelectCommand property itself is changed. Otherwise the InsertCommand, UpdateCommand, and DeleteCommand properties retain their previous values.

If you call Dispose, the VirtuosoCommandBuilder is disassociated from the VirtuosoDataAdapter, and the generated commands are no longer used.

Initializes a new instance of the VirtuosoCommandBuilder class.

public VirtuosoCommandBuilder();

Initializes a new instance of the VirtuosoCommandBuilder class with the associated VirtuosoDataAdapter object.

public VirtuosoCommandBuilder( VirtuosoDataAdapter  adapter );
adapter

A VirtuosoDataAdapter object to associate with this VirtuosoCommandBuilder.

The VirtuosoCommandBuilder registers itself as a listener for RowUpdating events that are generated by the VirtuosoDataAdapter specified in this property.

Gets or sets a VirtuosoDataAdapter object for which SQL statements are automatically generated.

public  VirtuosoDataAdapter  DataAdapter  ;

A VirtuosoDataAdapter object.

The VirtuosoCommandBuilder registers itself as a listener for RowUpdating events that are generated by the VirtuosoDataAdapter specified in this property.

Gets or sets the beginning character or characters to use when working with database objects (for example, tables or columns) whose names contain characters such as spaces.

public  string  QuotePrefix  ;

The beginning character or characters to use. The default is an empty string.

Database objects in Virtuoso servers can contain any valid characters, including spaces, commas, and semicolons. To accommodate this capability, use the QuotePrefix and QuoteSuffix properties to specify delimiters such as a left bracket and a right bracket to encapsulate the object name.

Gets or sets the ending character or characters to use when working with database objects (for example, tables or columns) whose names contain characters such as spaces.

public  string  QuotePrefix  ;

The ending character or characters to use. The default is an empty string.

Database objects in Virtuoso servers can contain any valid characters, including spaces, commas, and semicolons. To accommodate this capability, use the QuotePrefix and QuoteSuffix properties to specify delimiters such as a left bracket and a right bracket to encapsulate the object name.

Retrieves parameter information from the stored procedure specified in the VirtuosoCommand and populates the Parameters collection of the specified VirtuosoCommand object.

public static void DeriveParameters( VirtuosoCommand  command );
command

The VirtuosoCommand referencing the stored procedure from which the parameter information is to be derived. The derived parameters are added to the Parameters collection of the VirtuosoCommand.

DeriveParameters overwrites any existing parameter information for the VirtuosoCommand. DeriveParameters requires an extra call to the data server to obtain the information. If the parameter information is known in advance, it is more efficient to populate the parameters collection by setting the information explicitly.

For more information, see "Using Stored Procedures with a Command" in the Microsoft® .NET Framework SDK documentation.

Releases the unmanaged and, optionally, the managed resources used by the VirtuosoCommandBuilder.

protected override void Dispose( bool  disposing );
disposing

true to release both managed and unmanaged resources; false to release only unmanaged resources.

This method is called by the public Dispose method and the Finalize method. Dispose() invokes the protected Dispose(Boolean) method with the disposing parameter set to true. Finalize invokes Dispose with disposing set to false.

When the disposing parameter is true, the method releases all resources held by any managed objects that this VirtuosoCommand references. It does this by invoking the Dispose() method of each referenced object.

For more information about Dispose and Finalize, see "Cleaning Up Unmanaged Resources," and "Overriding the Finalize Method," in the .NET Framework SDK documentation.

Gets the automatically generated VirtuosoCommand object required to perform deletions on the Virtuoso database.

public VirtuosoCommand GetDeleteCommand();

The automatically generated VirtuosoCommand object required to perform deletions.

You can use the GetDeleteCommand method for informational or troubleshooting purposes because it returns the VirtuosoCommand object to be executed.

You can also use GetDeleteCommand as the basis of a modified command. For example, you might call GetDeleteCommand and modify the CommandTimeout value, and then explicitly set that on the VirtuosoDataAdapter.

After the SQL statement is first generated, you must explicitly call RefreshSchema if you change the statement in any way. Otherwise, the GetDeleteCommand still will be using information from the previous statement, which might not be correct. The SQL statements are first generated when the application calls either Update or GetDeleteCommand.

Gets the automatically generated VirtuosoCommand object required to perform insertions on the Virtuoso database.

public VirtuosoCommand GetInsertCommand();

The automatically generated VirtuosoCommand object required to perform insertions.

You can use the GetInsertCommand method for informational or troubleshooting purposes because it returns the VirtuosoCommand object to be executed.

You can also use GetInsertCommand as the basis of a modified command. For example, you might call GetInsertCommand and modify the CommandTimeout value, and then explicitly set that on the VirtuosoDataAdapter.

After the SQL statement is first generated, you must explicitly call RefreshSchema if you change the statement in any way. Otherwise, the GetInsertCommand still will be using information from the previous statement, which might not be correct. The SQL statements are first generated when the application calls either Update or GetInsertCommand.

Gets the automatically generated VirtuosoCommand object required to perform updates on the Virtuoso database.

public VirtuosoCommand GetUpdateCommand();

The automatically generated VirtuosoCommand object required to perform updates.

You can use the GetUpdateCommand method for informational or troubleshooting purposes because it returns the VirtuosoCommand object to be executed.

You can also use GetUpdateCommand as the basis of a modified command. For example, you might call GetUpdateCommand and modify the CommandTimeout value, and then explicitly set that on the VirtuosoDataAdapter.

After the SQL statement is first generated, you must explicitly call RefreshSchema if you change the statement in any way. Otherwise, the GetUpdateCommand still will be using information from the previous statement, which might not be correct. The SQL statements are first generated when the application calls either Update or GetUpdateCommand.

Refreshes the database schema information used to generate INSERT, UPDATE, or DELETE statements.

public void RefreshSchema();

You should call RefreshSchema whenever the SelectCommand value of the VirtuosoDataAdapter changes.

Represents an open connection to a Virtuoso database. This class cannot be inherited.

System.Object
System.MarshalByRefObject
System.ComponentModel.Component
VirtuosoConnection
 
              public 
              sealed 
              class 
              VirtuosoConnection
             extends, 
              Component
            
implements, ICloneable , IDbConnection {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

A VirtuosoConnection object represents a unique session to a Virtuoso database server.

The VirtuosoConnection object uses native resources such as network connection handles. You should always explicitly close any open VirtuosoConnection objects by calling Close or Dispose before the VirtuosoConnection object goes out of scope. Not doing so leaves the freeing of these native resources to garbage collection, which may not free them immediately. This, in turn, may eventually cause the underlying driver to run out of resources or reach a maximum limit, resulting in sporadic failures. For example, you might encounter Maximum Connections-related errors while a number of connections are waiting to be deleted by the garbage collector. Explicitly closing the connections by calling Close or Dispose allows a more efficient use of native resources, enhancing scalability and improving overall application performance.

Initializes a new instance of the VirtuosoConnection class.

Initializes a new instance of the VirtuosoConnection class.

public VirtuosoConnection();

When a new instance of VirtuosoConnection is created, the read/write properties are set to the following initial values unless they are specifically set using their associated keywords in the ConnectionString property.

Table 7.5. 

Properties Initial Value
ConnectionString empty string ("")
ConnectionTimeout 15
Database empty string ("")

You can change the value for these properties only by using the ConnectionString property

Initializes a new instance of the VirtuosoConnection class with the specified connection string.

public VirtuosoConnection( string  connectionString );
connectionString

The connection used to open the Virtuoso database.

When a new instance of VirtuosoConnection is created, the read/write properties are set to the following initial values unless they are specifically set using their associated keywords in the ConnectionString property.

Table 7.6. 

Properties Initial Value
ConnectionString connectionString
ConnectionTimeout 15
Database empty string ("")

You can change the value for these properties only by using the ConnectionString property

Gets or sets the string used to open a Virtuoso database.

public  string  ConnectionString  ;

The connection string that includes the source database name, and other parameters needed to establish the initial connection. The default value is an empty string.

IDbConnection.ConnectionString

The ConnectionString is similar to an OLE DB connection string, but is not identical. Unlike OLE DB or ADO, the connection string that is returned is the same as the user-set ConnectionString minus security information if the Persist Security Info value is set to false (default). The Virtuoso .NET Data Provider does not persist or return the password in a connection string unless you set Persist Security Info to true.

The ConnectionString property can be set only when the connection is closed. Many of the connection string values have corresponding read-only properties. When the connection string is set, all of these properties are updated, except when an error is detected. In this case, none of the properties are updated. VirtuosoConnection properties return only those settings contained in the ConnectionString.

Resetting the ConnectionString on a closed connection resets all connection string values (and related properties) including the password. For example, if you set a connection string that includes "Database=Demo", and then reset the connection string to "Data Source=myserver;User ID=dba;Password=dba", the Database property is no longer set to northwind.

The connection string is parsed immediately after being set. If errors in syntax are found when parsing, a runtime exception, such as ArgumentException, is generated. Other errors can be found only when an attempt is made to Open the connection.

Connection string has the following syntax. Each connection string is a sequence of settings Individual settings are separated by semicolons. Each setting is a pair of name and value delimited by the equal sign. Whitespace is ignored on either side of both names and values. Names are case insensitive. The value part can be quoted by either single or double quote characters or remain unquoted at all. However if it includes a semicolon, single quote, or double quote characters, it must be enclosed in either type of quotes. To embed the same character that is used for enclosing the value the character within the value must be doubled.

The following table lists the valid names for values within the ConnectionString.

Table 7.7. 

Name Default Description

Connect Timeout

-or-

Connection Timeout

15 The length of time (in seconds) to wait for a connection to the server before terminating the attempt and generating an error.
Connection Lifetime 0 When a connection is returned to the pool, its creation time is compared with the current time, and the connection is destroyed if that time span (in seconds) exceeds the value specified by connection lifetime. Useful in clustered configurations to force load balancing between a running server and a server just brought on-line.

Data Source

-or-

Server

-or-

Address

-or-

Network Address

  The name or network address of the instance of Virtuoso server to which to connect.
Encrypt false Specifies if the connection must be SSL encrypted. Currently encryption only works with an ODBC-based provider.
Enlist true When true, the pooler automatically enlists the connection in the creation thread's current transaction context.

Initial Catalog

-or-

Database

  The name of the database.
Max Pool Size 100 The maximum number of connections allowed in the pool.
Min Pool Size 0 The minimum number of connections allowed in the pool.

Password

-or-

Pwd

  The password for the Virtuoso account logging on.
Persist Security Info false When set to 'false', security-sensitive information, such as the password, is not returned as part of the connection if the connection is open or has ever been in an open State. Resetting the connection string resets all connection string values including the password
Pooling true When true, the VirtuosoConnection object is drawn from the appropriate pool, or if necessary, is created and added to the appropriate pool.

User ID

-or-

Uid

  The Virtuoso login name.

Gets or sets the time to wait while trying to establish a connection before terminating the attempt and generating an error.

public  int  ConnectionTimeout  ;

The time (in seconds) to wait for a connection to open. The default value is 15 seconds.

IDbConnection.ConnectionTimeout

A value of 0 indicates no limit, and should be avoided in a ConnectionString because an attempt to connect will wait indefinitely.

Gets the name of the current database or the database to be used after a connection is opened.

public  string  Database  ;

The name of the current database or the name of the database to be used once a connection is open. The default value is an empty string.

IDbConnection.Database

Initially, the Database property is set in the connection string. The Database property can be updated by using the ChangeDatabase method.

Gets the current state of the connection.

public  ConnectionState  State  ;

A bitwise combination of the ConnectionState values. The default is Closed.

The allowed state changes are:

  • From Closed to Open, using the Open method of the connection object.

  • From Open to Closed, using either the Close method or the Dispose method of the connection object.

Begins a database transaction.

Begins a database transaction.

public VirtuosoTransaction BeginTransaction();

An object representing the new transaction.

To commit or roll back the transaction, you must explicitly use the Commit or Rollback methods.

To ensure that the Virtuoso .NET Data Provider transaction management model performs correctly, avoid using other transaction management models, such as those provided by the data source.

Begins a database transaction with the specified isolation level.

public VirtuosoTransaction BeginTransaction( IsolationLevel  isoLevel );
isoLevel

The isolation level under which the transaction should run.

An object representing the new transaction.

To commit or roll back the transaction, you must explicitly use the Commit or Rollback methods.

To ensure that the Virtuoso .NET Data Provider transaction management model performs correctly, avoid using other transaction management models, such as those provided by the data source.

Changes the current database for an open VirtuosoConnection.

public void ChangeDatabase( string  database );
database

The name of the database to use in place of the current database.

IDbConnection.ChangeDatabase

The value parameter must contain a valid database name, and cannot contain a null value, an empty string (""), or a string with only blank characters.

Closes the connection to the database. This is the preferred method of closing any open connection.

public void Close();

IDbConnection.Close

The Close method rolls back any pending transactions. It then releases the connection to the connection pool, or closes the connection if connection pooling is disabled.

An application can call Close more than one time. No exception is generated.

Creates and returns a VirtuosoCommand object associated with the VirtuosoConnection.

public VirtuosoCommand CreateCommand();

A VirtuosoCommand object.

Enlists in the specified transaction as a distributed transaction.

public void EnlistDistributedTransaction( ITransaction  transaction );
transaction

A reference to an existing transaction in which to enlist or null to unenlist.

You can enlist in an existing distributed transaction using the EnlistDistributedTransaction method if auto-enlistment is disabled. Enlisting in an existing distributed transaction ensures that, if the transaction is committed or rolled back, modifications made by the code at the data source are also committed or rolled back.

This member supports the Microsoft® .NET Framework infrastructure and is not intended to be used directly from your code.

object ICloneable.Clone();

This member supports the Microsoft® .NET Framework infrastructure and is not intended to be used directly from your code.

This member supports the Microsoft® .NET Framework infrastructure and is not intended to be used directly from your code.

IDbTransaction IDbConnection.BeginTransaction();

This member supports the Microsoft® .NET Framework infrastructure and is not intended to be used directly from your code.

IDbTransaction IDbConnection.BeginTransaction( IsolationLevel  isoLevel );

This member supports the Microsoft® .NET Framework infrastructure and is not intended to be used directly from your code.

IDbCommand IDbConnection.CreateCommand();

Opens a database connection with the property settings specified by the ConnectionString.

public void Open();

IDbConnection.Open

The VirtuosoConnection draws an open connection from the connection pool if one is available. Otherwise, it establishes a new connection to an instance of Virtuoso server.

[Note] Note:

If the VirtuosoConnection goes out of scope, it is not closed. Therefore, you must explicitly close the connection by calling Close or Dispose.

Represents a set of data commands and a connection to a data source that are used to fill the DataSet and update the data source. This class cannot be inherited.

System.Object
System.MarshalByRefObject
System.ComponentModel.Component
System.Data.Common.DataAdapter
System.Data.Common.DbDataAdapter
VirtuosoDataAdapter
 
              public 
              sealed 
              class 
              VirtuosoDataAdapter
             extends, 
              DbDataAdapter
            
implements, IDbDataAdapter {
}

Any public static (Shared in Microsoft® Visual Basic®) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

The VirtuosoDataAdapter serves as a bridge between a DataSet and data source for retrieving and saving data. The VirtuosoDataAdapter provides this bridge by using Fill to load data from the data source into the DataSet, and using Update to send changes made in the DataSet back to the data source.

The VirtuosoDataAdapter also includes the SelectCommand, InsertCommand, DeleteCommand, UpdateCommand, and TableMappings properties to facilitate loading and updating of data.

Initializes a new instance of the VirtuosoDataAdapter class.

public VirtuosoDataAdapter();

When you create an instance of VirtuosoDataAdapter, the following read/write properties are set to their default values, as shown in the table.

Table 7.8. 

Properties Default Value
MissingMappingAction MissingMappingAction.Passthrough
MissingSchemaAction MissingSchemaAction.Add

You can change the value of any of these properties through a separate call to the property.

Initializes a new instance of the VirtuosoDataAdapter class with the specified VirtuosoCommand as the SelectCommand property.

public VirtuosoDataAdapter( VirtuosoCommand  selectCommand );
selectCommand

A VirtuosoCommand that is an SQL SELECT statement or stored procedure, and is set as the SelectCommand property of the VirtuosoDataAdapter.

This implementation of the VirtuosoDataAdapter constructor sets the SelectCommand property to the value specified in the selectCommand parameter.

When you create an instance of VirtuosoDataAdapter, the following read/write properties are set to their default values, as shown in the table.

Table 7.9. 

Properties Default Value
MissingMappingAction MissingMappingAction.Passthrough
MissingSchemaAction MissingSchemaAction.Add

You can change the value of any of these properties through a separate call to the property.

Initializes a new instance of the VirtuosoDataAdapter class with an SQL SELECT statement and a VirtuosoConnection.

public VirtuosoDataAdapter( string  selectCommandText ,
                            VirtuosoConnection  selectConnection );
selectCommandText

A string that is a SQL SELECT statement or stored procedure to be used by the SelectCommand property of the VirtuosoDataAdapter.

selectConnection

A VirtuosoConnection that represents the connection.

Initializes a new instance of the VirtuosoDataAdapter class with an SQL SELECT statement and a connection string.

public VirtuosoDataAdapter( string  selectCommandText ,
                            string  selectConnectionString );
selectCommandText

A string that is a SQL SELECT statement or stored procedure to be used by the SelectCommand property of the VirtuosoDataAdapter.

selectConnectionString

The connection string.

Gets or sets an SQL statement or stored procedure used to delete records in the data source.

public  VirtuosoCommand  DeleteCommand  ;

A VirtuosoCommand used during an update operation to delete records in the database that correspond to deleted rows in the DataSet.

When DeleteCommand is assigned to a previously created VirtuosoCommand, the VirtuosoCommand is not cloned. The DeleteCommand maintains a reference to the previously created VirtuosoCommand object.

Gets or sets an SQL statement or stored procedure used to insert new records in the data source.

public  VirtuosoCommand  InsertCommand  ;

A VirtuosoCommand used during an update operation to insert records in the database that correspond to new rows in the DataSet.

When InsertCommand is assigned to a previously created VirtuosoCommand, the VirtuosoCommand is not cloned. The InsertCommand maintains a reference to the previously created VirtuosoCommand object.

Gets or sets an SQL statement or stored procedure used to select records in the data source.

public  VirtuosoCommand  SelectCommand  ;

A VirtuosoCommand used during Fill to select records from the database for placement in the DataSet.

When SelectCommand is assigned to a previously created VirtuosoCommand, the VirtuosoCommand is not cloned. The SelectCommand maintains a reference to the previously created VirtuosoCommand object.

If the SelectCommand does not return any rows, no tables are added to the DataSet, and no exception is raised.

Gets or sets an SQL statement or stored procedure used to update records in the data source.

public  VirtuosoCommand  UpdateCommand  ;

A VirtuosoCommand used during an update operation to update records in the database that correspond to modified rows in the DataSet.

When UpdateCommand is assigned to a previously created VirtuosoCommand, the VirtuosoCommand is not cloned. The UpdateCommand maintains a reference to the previously created VirtuosoCommand object.

This member overrides DbDataAdapter.CreateRowUpdatedEvent.

protected override RowUpdatedEventArgs CreateRowUpdatedEvent( DataRow  dataRow ,
                                                              IDbCommand  command ,
                                                              StatementType  statementType ,
                                                              DataTableMapping  tableMapping );

This member overrides DbDataAdapter.CreateRowUpdatingEvent.

protected override RowUpdatedEventArgs CreateRowUpdatingEvent( DataRow  dataRow ,
                                                               IDbCommand  command ,
                                                               StatementType  statementType ,
                                                               DataTableMapping  tableMapping );

Raises the RowUpdated event.

protected override void OnRowUpdated( RowUpdatedEventArgs  value );
value

A System.Data.Common.RowUpdatedEventArgs object that contains the event data.

Raising an event invokes the event handler through a delegate. For an overview, see "Raising an Event" in the Microsoft® .NET Framework SDK documentation.

Raises the RowUpdating event.

protected override void OnRowUpdating( RowUpdatingEventArgs  value );
value

A System.Data.Common.RowUpdatingEventArgs object that contains the event data.

Raising an event invokes the event handler through a delegate. For an overview, see "Raising an Event" in the Microsoft® .NET Framework SDK documentation.

Occurs during an Update operation after a command is executed against the data source.

public  event  VirtuosoRowUpdatedEventHandler  RowUpdated  ;

The event handler receives an argument of type VirtuosoRowUpdatedEventArgs containing data related to this event. The following VirtuosoRowUpdatedEventArgs properties provide information specific to this event.

Table 7.10. 

Property Description
Command Gets the VirtuosoCommand executed when Update is called.
Errors (inherited from RowUpdatedEventArgs) Gets any errors generated by the .NET data provider when the Command was executed.
RecordsAffected (inherited from RowUpdatedEventArgs) Gets the number of rows changed, inserted, or deleted by execution of the SQL statement.
Row (inherited from RowUpdatedEventArgs) Gets the DataRow sent through an Update.
StatementType (inherited from RowUpdatedEventArgs) Gets the type of SQL statement executed.
Status (inherited from RowUpdatedEventArgs) Gets the UpdateStatus of the Command.
TableMapping (inherited from RowUpdatedEventArgs) Gets the DataTableMapping sent through an Update.

When using the Update method, there are two events that occur per data row updated. The order of execution is as follows:

  1. The values in the DataRow are moved to the parameter values.

  2. The OnRowUpdating event is raised.

  3. The command executes.

  4. If the UpdateRowSource enumeration is set to FirstReturnedRecord, the first returned result is placed in the DataRow.

  5. If there are output parameters, they are placed in the DataRow.

  6. The OnRowUpdated event is raised.

  7. AcceptChanges is called.

Occurs during an Update operation before a command is executed against the data source.

public  event  VirtuosoRowUpdatingEventHandler  RowUpdating  ;

The event handler receives an argument of type VirtuosoRowUpdatingEventArgs containing data related to this event. The following VirtuosoRowUpdatingEventArgs properties provide information specific to this event.

Table 7.11. 

Property Description
Command Gets or sets the VirtuosoCommand to execute when Update is called.
Errors (inherited from RowUpdatingEventArgs) Gets any errors generated by the .NET data provider when the Command executes.
Row (inherited from RowUpdatingEventArgs) Gets the DataRow to send through an Update.
StatementType (inherited from RowUpdatingEventArgs) Gets the type of SQL statement to execute.
Status (inherited from RowUpdatingEventArgs) Gets the UpdateStatus of the Command.
TableMapping (inherited from RowUpdatingEventArgs) Gets the DataTableMapping to send through the Update.

When using the Update method, there are two events that occur per data row updated. The order of execution is as follows:

  1. The values in the DataRow are moved to the parameter values.

  2. The OnRowUpdating event is raised.

  3. The command executes.

  4. If the UpdateRowSource enumeration is set to FirstReturnedRecord, the first returned result is placed in the DataRow.

  5. If there are output parameters, they are placed in the DataRow.

  6. The OnRowUpdated event is raised.

  7. AcceptChanges is called.

Provides a means of reading a forward-only stream of rows from a Virtuoso database. This class cannot be inherited.

System.Object
System.MarshalByRefObject
VirtuosoDataReader
 
              public 
              sealed 
              class 
              VirtuosoDataReader
             extends, 
              MarshalByRefObject
            
implements, IDataReader , IDataRecord , IDisposable , IEnumerable {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

To create a VirtuosoDataReader, you must call the ExecuteReader method of the VirtuosoCommand object, rather than directly using a constructor.

Changes made to a resultset by another process or thread while data is being read may be visible to the user of the VirtuosoDataReader. However, the precise behavior is both driver and timing dependent.

IsClosed and RecordsAffected are the only properties that you can call after the VirtuosoDataReader is closed. In some cases, you must call Close before you can call RecordsAffected.

Gets a value indicating the depth of nesting for the current row.

public  int  Depth  ;

The depth of nesting for the current row.

IDataReader.Depth

The outermost table has a depth of zero. The Virtuoso .NET Data Provider does not support nesting and always returns zero.

Gets the number of columns in the current row.

public  int  FieldCount  ;

When not positioned in a valid record set, 0; otherwise the number of columns in the current record. The default is -1.

IDataRecord.FieldCount

After executing a query that does not return rows, FieldCount returns 0.

Gets a value indicating whether the data reader is closed.

public  bool  IsClosed  ;

true if the VirtuosoDataReader is closed; otherwise, false .

IDataReader.IsClosed

IsClosed and RecordsAffected are the only properties that you can call after the VirtuosoDataReader is closed.

Gets the value of the specified column in its native format given the column ordinal.

public  object  this[int i]  ;
i

The zero-based column ordinal.

The value of the specified column in its native format.

IDataRecord.Item

Gets the value of the specified column in its native format given the column name.

public  object  this[string name]  ;
name

The column name.

The value of the specified column in its native format.

IDataRecord.Item

Gets the number of rows changed, inserted, or deleted by execution of the SQL statement.

public  int  RecordsAffected  ;

The number of rows changed, inserted, or deleted; 0 if no rows were affected or the statement failed; and -1 for SELECT statements.

IDataReader.RecordsAffected

IsClosed and RecordsAffected are the only properties that you can call after the VirtuosoDataReader is closed.

Closes the VirtuosoDataReader object.

public void Close();

IDataReader.Close

You must explicitly call the Close method when you are through using the VirtuosoDataReader to use the associated VirtuosoConnection for any other purpose.

The Close method fills in the values for output parameters, return values and RecordsAffected.

Gets the value of the specified column as a Boolean.

public bool GetBoolean( int  i );
i

The zero-based column ordinal.

A Boolean that is the value of the column.

IDataRecord.GetBoolean

Call IsDBNull to check for null values before calling this method.

public byte GetByte( int  i );
i

The zero-based column ordinal.

The value of the specified column as a byte.

IDataRecord.GetByte

Call IsDBNull to check for null values before calling this method.

Reads a stream of bytes from the specified column offset into the buffer as an array, starting at the given buffer offset.

public long GetBytes( int  i ,
                      long  fieldOffset ,
                      byte[]  buffer ,
                      int  bufferOffset ,
                      int  length );
i

The zero-based column ordinal.

fieldOffset

The index within the field from which to begin the read operation.

buffer

The buffer into which to read the stream of bytes.

bufferOffset

The index for buffer to begin the read operation.

length

The number of bytes to read.

The actual number of bytes read.

IDataRecord.GetBytes

GetBytes returns the number of available bytes in the field. In most cases this is the exact length of the field. However, the number returned may be less than the true length of the field if GetBytes has already been used to obtain bytes from the field. This may be the case, for example, if the VirtuosoDataReader is reading a large data structure into a buffer. For more information, see the SequentialAccess setting of System.Data.CommandBehavior in the Microsoft® .NET Framework SDK documentation.

If you pass a buffer that is a null value, GetBytes returns the length of the field in bytes.

public char GetChar( int  i );
i

The zero-based column ordinal.

The value of the specified column as a character.

IDataRecord.GetChar

Call IsDBNull to check for null values before calling this method.

Reads a stream of characters from the specified column offset into the buffer as an array, starting at the given buffer offset.

public long GetChars( int  i ,
                      long  fieldOffset ,
                      char[]  buffer ,
                      int  bufferOffset ,
                      int  length );
i

The zero-based column ordinal.

fieldOffset

The index within the field from which to begin the read operation.

buffer

The buffer into which to copy data..

bufferOffset

The index for buffer to begin the read operation.

length

The number of characters to read.

The actual number of characters read.

IDataRecord.GetChars

GetChars returns the number of available characters in the field. In most cases this is the exact length of the field. However, the number returned may be less than the true length of the field if GetChars has already been used to obtain characters from the field. This may be the case, for example, if the VirtuosoDataReader is reading a large data structure into a buffer. For more information, see the SequentialAccess setting of System.Data.CommandBehavior in the Microsoft® .NET Framework SDK documentation.

If you pass a buffer that is a null value. GetChars returns the length of the field in characters.

Not currently supported.

public IDataReader GetData( int  i );

IDataRecord.GetData

Gets the name of the source data type.

public string GetDataTypeName( int  i );
i

The zero-based column ordinal.

The name of the source data type.

IDataRecord.GetDataTypeName

Gets the value of the specified column as a DateTime object.

public DateTime GetDateTime( int  i );
i

The zero-based column ordinal.

The value of the specified column as a DateTime object.

IDataRecord.GetDateTime

Call IsDBNull to check for null values before calling this method.

Gets the value of the specified column as a Decimal object.

public decimal GetDecimal( int  i );
i

The zero-based column ordinal.

The value of the specified column as a Decimal object.

IDataRecord.GetDecimal

Call IsDBNull to check for null values before calling this method.

public double GetDouble( int  i );
i

The zero-based column ordinal.

The value of the specified column as a double-precision floating point number.

IDataRecord.GetDouble

Call IsDBNull to check for null values before calling this method.

Gets the Type that is the data type of the object.

public Type GetFieldType( int  i );
i

The zero-based column ordinal.

The Type that is the data type of the object.

IDataRecord.GetFieldType

public float GetFloat( int  i );
i

The zero-based column ordinal.

The value of the specified column as a single-precision floating-point number.

IDataRecord.GetFloat

Call IsDBNull to check for null values before calling this method.

Gets the value of the specified column as a globally-unique identifier (GUID).

public Guid GetGuid( int  i );
i

The zero-based column ordinal.

The value of the specified column as a GUID.

IDataRecord.GetGuid

Call IsDBNull to check for null values before calling this method.

Gets the value of the specified column as a 16-bit signed integer.

public short GetInt16( int  i );
i

The zero-based column ordinal.

The value of the specified column as a 16-bit signed integer.

IDataRecord.GetInt16

Call IsDBNull to check for null values before calling this method.

Gets the value of the specified column as a 32-bit signed integer

public int GetInt32( int  i );
i

The zero-based column ordinal.

The value of the specified column as a 32-bit signed integer.

IDataRecord.GetInt32

Call IsDBNull to check for null values before calling this method.

Gets the value of the specified column as a 64-bit signed integer.

public long GetInt64( int  i );
i

The zero-based column ordinal.

The value of the specified column as a 64-bit signed integer.

IDataRecord.GetInt64

Call IsDBNull to check for null values before calling this method.

Gets the name of the specified column.

public string GetName( int  i );
i

The zero-based column ordinal.

A string that is the name of the specified column.

IDataRecord.GetName

Gets the column ordinal, given the name of the column.

public int GetOrdinal( string  name );
name

The name of the column.

The zero-based column ordinal.

IDataRecord.GetOrdinal

Returns a DataTable that describes the column metadata of the VirtuosoDataReader.

public DataTable GetSchemaTable();

A DataTable that describes the column metadata.

IDataReader.GetSchemaTable

For the GetSchemaTable method returns metadata about each column in the following order:

Table 7.12. 

DataReader Column Description
ColumnName The name of the column; this might not be unique. If the column name cannot be determined, a null value is returned. This name always reflects the most recent naming of the column in the current view or command text.
ColumnOrdinal The ordinal of the column. This is zero for the bookmark column of the row, if any. Other columns are numbered starting with one. This column cannot contain a null value.
ColumnSize The maximum possible length of a value in the column. For columns that use a fixed-length data type, this is the size of the data type.
NumericPrecision If ProviderType is a numeric data type, this is the maximum precision of the column. The precision depends on the definition of the column. If ProviderType is not a numeric data type, this is a null value.
NumericScale If ProviderType is decimal, the number of digits to the right of the decimal point. Otherwise, this is a null value.
DataType Maps to the .Net Framework type of the column.
ProviderType The indicator of the column's data type. If the data type of the column varies from row to row, this must be Object. This column cannot contain a null value.
IsLong Set if the column contains a Binary Long Object (BLOB) that contains very long data.
AllowDBNull Set if the consumer can set the column to a null value or if the provider cannot determine whether or not the consumer can set the column to a null value. Otherwise, not set. A column may contain null values, even if it cannot be set to a null value.
IsReadOnly true if the column can be modified; otherwise false .
IsRowVersion  
IsUnique true : No two rows in the base table-the table returned in BaseTableName-can have the same value in this column. IsUnique is guaranteed to be true if the column constitutes a key by itself or if there is a constraint of type UNIQUE that applies only to this column. false : The column can contain duplicate values in the base table. The default of this column is false .
IsKey true : The column is one of a set of columns in the rowset that, taken together, uniquely identify the row. The set of columns with IsKey set to true must uniquely identify a row in the rowset. There is no requirement that this set of columns is a minimal set of columns. This set of columns may be generated from a base table primary key, a unique constraint or a unique index. false : The column is not required to uniquely identify the row.
IsAutoIncrement true : The column assigns values to new rows in fixed increments. false : The column does not assign values to new rows in fixed increments. The default of this column is false .
BaseSchemaName The name of the schema in the data store that contains the column. A null value if the base schema name cannot be determined. The default of this column is a null value.
BaseCatalogName The name of the catalog in the data store that contains the column. NULL if the base catalog name cannot be determined. The default of this column is a null value.
BaseTableName The name of the table or view in the data store that contains the column. A null value if the base table name cannot be determined. The default of this column is a null value.
BaseColumnName The name of the column in the data store. This might be different than the column name returned in the ColumnName column if an alias was used. A null value if the base column name cannot be determined or if the rowset column is derived, but not identical to, a column in the data store. The default of this column is a null value.

Gets the value of the specified column as a string.

public string GetString( int  i );
i

The zero-based column ordinal.

The value of the specified column as a string.

IDataRecord.GetString

Call IsDBNull to check for null values before calling this method.

Gets the value of the column at the specified ordinal in its native format.

public object GetValue( int  i );
i

The zero-based column ordinal.

The value to return.

IDataRecord.GetValue

This method returns DBNull for null database columns.

Gets all the attribute columns in the current row.

public int GetValues( object[]  values );
values

An array of type Object into which to copy the attribute columns.

The number of instances of Object in the array.

IDataRecord.GetValues

For most applications, the GetValues method provides an efficient means for retrieving all columns, rather than retrieving each column individually.

You can pass an Object array that contains fewer than the number of columns contained in the resulting row. Only the amount of data the Object array holds is copied to the array. You can also pass an Object array whose length is more than the number of columns contained in the resulting row.

This method returns DBNull for null database columns.

This member supports the Microsoft® .NET Framework infrastructure and is not intended to be used directly from your code.

void IDisposable.Dispose();

This member supports the Microsoft® .NET Framework infrastructure and is not intended to be used directly from your code.

IEnumerable IEnumerable.GetEnumerator();

Gets a value indicating whether the column contains non-existent or missing values.

public bool IsDBNull( int  i );
i

The zero-based column ordinal.

true if the specified column value is equivalent to DBNull; otherwise, false .

IDataRecord.IsDBNull

To avoid raising an error, call this method to check for null column values before calling the typed Get methods (for example, GetByte, GetChar, and so on).

Advances the VirtuosoDataReader to the next result, when reading the results of batch SQL statements.

public bool NextResult();

true if there are more result sets; otherwise, false .

IDataReader.NextResult

Used to process multiple results, which can be generated by executing batch SQL statements.

By default, the VirtuosoDataReader is positioned on the first result.

Advances the VirtuosoDataReader to the next record.

public bool Read();

true if there are more rows; otherwise, false .

IDataReader.Read

The default position of the VirtuosoDataReader is prior to the first record. Therefore, you must call Read to begin accessing any data.

Collects information relevant to a warning or error returned by Virtuoso server. This class cannot be inherited.

System.Object
VirtuosoError
 
              public 
              sealed 
              class 
              VirtuosoError
             {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

This class is created by the Virtuoso .NET Data Provider when an error occurs. An instance of VirtuosoError is created and managed by the VirtuosoErrorCollection, which in turn is created by the VirtuosoException class.

Gets a short description of the error.

public  string  Message  ;

A description of the error.

Gets the five-character error code that follows the ANSI SQL standard for the database.

public  string  SQLState  ;

The five-character error code, which identifies the source of the error.

Collects all errors generated by the Virtuoso .NET Data Provider. This class cannot be inherited.

System.Object
VirtuosoErrorCollection
 
              public 
              sealed 
              class 
              VirtuosoErrorCollection
            implements, 
              ICollection
             {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

This class is created by VirtuosoException to collect instances of the VirtuosoError class. VirtuosoErrorCollection always contains at least one instance of the VirtuosoError class.

Gets the number of errors in the collection.

public  int  Count  ;

The total number of errors in the collection.

ICollection.Count

Gets the error at the specified index.

public  VirtuosoError  this[int i]  ;
i

The zero-based index of the error to retrieve.

A VirtuosoError that contains the error at the specified index.

Copies the elements of the VirtuosoErrorCollection into an array, starting at the given index within the array.

public void CopyTo( Array  array ,
                    int  i );
array

The array into which to copy the elements.

i

The starting index of array.

ICollection.CopyTo

This member supports the Microsoft® .NET Framework infrastructure and is not intended to be used directly from your code.

IEnumerable IEnumerable.GetEnumerator();

The exception that is thrown when Virtuoso server returns a warning or error. This class cannot be inherited.

System.Object
System.Exception
System.SystemException
VirtuosoException
 
              public 
              sealed 
              class 
              VirtuosoException
             extends, 
              SystemException
             {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

This class is created whenever the Virtuoso .NET Data Provider encounters an error generated by the server (Client-side errors are raised as standard common language runtime exceptions.). It always contains at least one instance of VirtuosoError.

Gets a collection of one or more VirtuosoError objects that give detailed information about exceptions generated by the Virtuoso .NET Data Provider.

public  VirtuosoErrorCollection  Errors  ;

The collected instances of the VirtuosoError class.

This property is a wrapper for the VirtuosoErrorCollection.

Gets the text describing the error.

public  string  Message  ;

The text describing the error.

This is a wrapper for the Message property of the first VirtuosoError in the Errors property.

Provides data for the InfoMessage event. This class cannot be inherited.

System.Object
System.EventArgs
VirtuosoInfoMessageEventArgs
 
              public 
              sealed 
              class 
              VirtuosoInfoMessageEventArgs
             extends, 
              EventArgs
             {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

The InfoMessage event contains a VirtuosoErrorCollection collection with warnings sent from the Virtuoso srver.

Gets the collection of warnings sent from the Virtuoso server.

public  VirtuosoErrorCollection  Errors  ;

The collection of warnings sent from the server.

Represents the method that will handle the InfoMessage event of a VirtuosoConnection.

public delegate void VirtuosoInfoMessageEventHandler( object  sender ,
                                                      VirtuosoInfoMessageEventArgs  e );

The declaration of your event handler must have the same parameters as the VirtuosoInfoMessageEventHandler delegate declaration.

sender

The source of the event.

e

A VirtuosoInfoMessageEventArgs object that contains the event data.

When you create a VirtuosoInfoMessageEventArgs delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event handler delegates, see "Events and Delegates" in the .NET Framework SDK documentation.

Represents a parameter to an VirtuosoCommand and optionally, its mapping to a DataColumn. This class cannot be inherited.

System.Object
System.MarshalByRefObject
VirtuosoParameter
 
              public 
              sealed 
              class 
              VirtuosoParameter
             extends, 
              MarshalByRefObject
            
implements, IDbDataParameter , IDataParameter , ICloneable {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

Initializes a new instance of the VirtuosoParameter class.

public VirtuosoParameter();

Initializes a new instance of the VirtuosoParameter class with the parameter name and value.

public VirtuosoParameter( string  parameterName ,
                          object  object );
parameterName

The name of the parameter to map.

value

An Object that is the value of the VirtuosoParameter.

When you specify an Object in the value parameter, the VirtDbType is inferred from the .NET Framework type of the Object.

Initializes a new instance of the VirtuosoParameter class with the parameter name and the data type.

public VirtuosoParameter( string  parameterName ,
                          VirtDbType  dbType );
parameterName

The name of the parameter to map.

dbType

One of the VirtDbType values.

The data type, and if appropriate, Size and Precision are inferred from the value of the dbType parameter.

Initializes a new instance of the VirtuosoParameter class with the parameter name, the VirtDbType, and the size.

public VirtuosoParameter( string  parameterName ,
                          VirtDbType  dbType ,
                          int  size );
parameterName

The name of the parameter to map.

dbType

One of the VirtDbType values.

size

The width of the parameter.

The Size is inferred from the value of the dbType parameter if it is not explicitly set in the size parameter.

Initializes a new instance of the VirtuosoParameter class with the parameter name, VirtDbType, size, and source column name.

public VirtuosoParameter( string  parameterName ,
                          VirtDbType  dbType ,
                          int  size ,
                          string  sourceColumn );
parameterName

The name of the parameter to map.

dbType

One of the VirtDbType values.

size

The width of the parameter.

sourceColumn

The name of the source column.

The Size is inferred from the value of the dbType parameter if it is not explicitly set in the size parameter.

Initializes a new instance of the VirtuosoParameter class with the parameter name, the type of the parameter, the size of the parameter, a ParameterDirection, the precision of the parameter, the scale of the parameter, the source column, a DataRowVersion to use, and the value of the parameter.

public VirtuosoParameter( string  parameterName ,
                          VirtDbType  dbType ,
                          int  size ,
                          ParameterDirection  direction ,
                          bool  isNullable ,
                          byte  precision ,
                          byte  scale ,
                          string  sourceColumn ,
                          DataRowVersion  sourceVersion ,
                          object  value );
parameterName

The name of the parameter to map.

dbType

One of the VirtDbType values.

size

The width of the parameter.

direction

One of the System.Data.ParameterDirection values.

isNullable

true if the value of the field can be null, otherwise false .

precision

The total number of digits to the left and right of the decimal point to which Value is resolved.

scale

The total number of decimal places to which Value is resolved.

sourceColumn

The name of the source column.

sourceVersion

One of the System.Data.DataRowVersion values.

value

An Object that is the value of the VirtuosoParameter.

The Size and Precision are inferred from the value of the dbType parameter if they are not explicitly set in the size and precision parameters.

Gets or sets the DbType of the parameter.

public  DbType  DbType  ;

One of the System.Data.DbType values. The default is String.

IDataParameter.DbType

The VirtDbType and DbType are linked. Therefore, setting the DbType changes the VirtDbType to a supporting VirtDbType.

For a list of the supported data types, see the appropriate VirtDbType member.

Gets or sets a value indicating whether the parameter is input-only, output-only, bidirectional, or a stored procedure return value parameter.

public  ParameterDirection  Direction  ;

One of the System.Data.ParameterDirection values. The default is Input.

IDataParameter.Direction

If the ParameterDirection is Output, and execution of the associated VirtuosoCommand does not return a value, the VirtuosoParameter will contain a null value. Null values are handled using the DBNull class. After the last row from the last resultset is read, the Output, InputOut, and ReturnValue parameters are updated.

Gets or sets a value indicating whether the parameter accepts null values.

public  bool  IsNullable  ;

true if null values are accepted; otherwise, false . The default is false .

IDataParameter.IsNullable

Null values are handled using the System.DBNull class.

Gets or sets the name of the VirtuosoParameter.

public  string  ParameterName  ;

The name of the VirtuosoParameter. The default is an empty string ("").

IDataParameter.ParameterName

Instead of named parameters, the Virtuoso .NET Data Provider uses positional parameters that are marked with a question mark (?) in the syntax of the command text. Parameter objects in the VirtuosoParameterCollection and the actual parameters accepted by the stored procedure or parameterized SQL statement correspond to each other based on the order in which the VirtuosoParameter objects are inserted into the collection rather than by parameter name. Parameter names can be supplied, but will be ignored during parameter object binding.

Gets or sets the maximum number of digits used to represent the Value property.

public  byte  Precision  ;

The maximum number of digits used to represent the Value property. The default value is 0.

IDbDataParameter.Precision

The Precision property is used only for decimal and numeric input parameters.

Gets or sets the number of decimal places to which Value is resolved.

public  byte  Scale  ;

The number of decimal places to which Value is resolved. The default is 0.

IDbDataParameter.Scale

The Scale property is used only for decimal and numeric input parameters.

Gets or sets the maximum size, in bytes, of the data within the column.

public  int  Size  ;

The maximum size, in bytes, of the data within the column. The default value is inferred from the parameter value.

IDbDataParameter.Size

The Size property is used for binary and string types.

For variable-length data types, the Size property describes the maximum amount of data to transmit to the server. For example, for a string value, the Size property could be used to limit the amount of data sent to the server to the first one hundred bytes.

For nonstring data types and ANSI string data, the Size property refers to the number of bytes. For Unicode string data, the Size property refers to the number of characters. The count for strings does not include the terminating character.

If not explicitly set, the value of Size is inferred from the actual size of the specified parameter value.

For fixed-width data types, the value of Size is ignored. It can be retrieved for informational purposes, and returns the maximum amount of bytes the provider uses when transmitting the value of the parameter to the server.

Gets or sets the name of the source column mapped to the DataSet and used for loading or returning the Value.

public  string  SourceColumn  ;

The name of the source column that will be used to set the value of this parameter. The default is an empty string ("").

IDataParameter.SourceColumn

When SourceColumn is set to anything other than an empty string, the value of the parameter is retrieved from the column with the SourceColumn name. If Direction is set to Input, the value is taken from the DataSet. If Direction is set to Output, the value is taken from the data source. A Direction of InputOutput is a combination of both.

Gets or sets the DataRowVersion to use when loading Value.

public  DataRowVersion  DataRowVersion  ;

One of the System.Data.DataRowVersion values. The default is Current.

IDataParameter.SourceVersion

The SourceVersion is used by UpdateCommand during an Update operation to determine whether the parameter value is set to Current or Original. This allows primary keys to be updated. This property is ignored by InsertCommand and DeleteCommand.

This property is set to the version of the DataRow used by either the Item property (DataRow indexer), or the GetChildRows method of the DataRow object.

Gets or sets the value of the parameter.

public  object  Value  ;

An Object that is the value of the parameter. The default value is null.

IDataParameter.Value

For input parameters, the value is bound to the VirtuosoCommand that is sent to the server. For output and return-value parameters, the value is set on completion of the VirtuosoCommand and after the VirtuosoDataReader is closed.

When sending a null parameter value to the server, the user must specify DBNull, not null. A null value in the system is an empty object that has no value. DBNull is used to represent null values.

If the application specifies the database type, the bound value is converted to that type when the provider sends the data to the server. The provider attempts to convert any type of value if it supports the IConvertible interface. Conversion errors may result if the specified type is not compatible with the value.

Both the DbType and VirtDbType properties can be inferred by setting Value. If applicable, the size, precision and scale will also be inferred from Value.

The Value property is overwritten by the Update method.

Gets or sets the VirtDbType of the parameter.

public  VirtDbType  VirtDbType  ;

One of the VirtDbType values. The default is NVarChar.

The VirtDbType and DbType are linked. Therefore, setting the DbType changes the VirtDbType to a supporting VirtDbType.

For a list of the supported data types, see the appropriate VirtDbType member. For more information, see "Using Parameters with a DataAdapter" in the Microsoft® .NET Framework SDK documentation.

This member supports the Microsoft® .NET Framework infrastructure and is not intended to be used directly from your code.

object ICloneable.Clone();

Gets a string containing the ParameterName.

public override string ToString();

A string containing the ParameterName.

Represents a collection of parameters relevant to a VirtuosoCommand as well as their respective mappings to columns in a DataSet. This class cannot be inherited.

System.Object
System.MarshalByRefObject
VirtuosoParameterCollection
 
              public 
              sealed 
              class 
              VirtuosoParameterCollection
             extends, 
              MarshalByRefObject
            
implements, IDataParameterCollection , ICollection , IEnumerable , IList {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

Gets the number of VirtuosoParameter objects in the collection.

public  int  Count  ;

The number of VirtuosoParameter objects in the collection.

ICollection.Count

Gets or sets the VirtuosoParameter at the specified index.

public  object  this[int i]  ;
index

The zero-based index of the parameter to retrieve.

The VirtuosoParameter at the specified index.

Gets or sets the VirtuosoParameter with the specified name.

public  object  this[string parameterName]  ;
parameterName

The name of the parameter to retrieve.

The VirtuosoParameter with the specified name.

Adds the specified VirtuosoParameter object to the VirtuosoParameterCollection.

public int Add( object  value );
value

The VirtuosoParameter to add to the collection.

The index in the collection of the new VirtuosoParameter object.

IList.Add

Adds the specified VirtuosoParameter object to the VirtuosoParameterCollection.

public VirtuosoParameter Add( VirtuosoParameter  value );
value

The VirtuosoParameter to add to the collection.

A reference to the new VirtuosoParameter object.

Adds a VirtuosoParameter to the VirtuosoParameterCollection with the specified parameter name and value.

public VirtuosoParameter Add( string  parameterName ,
                              object  value );
parameterName

The name of the parameter.

value

The Value of the VirtuosoParameter to add to the collection.

The new VirtuosoParameter object.

Adds a VirtuosoParameter to the VirtuosoParameterCollection with the specified parameter name and data type.

public VirtuosoParameter Add( string  parameterName ,
                              VirtDbType  dbType );
parameterName

The name of the parameter.

value

One of the VirtDbType values.

The new VirtuosoParameter object.

Adds a VirtuosoParameter to the VirtuosoParameterCollection with the specified parameter name, data type, and parameter size.

public VirtuosoParameter Add( string  parameterName ,
                              VirtDbType  dbType ,
                              int  size );
parameterName

The name of the parameter.

value

One of the VirtDbType values.

size

The size of the parameter (width of the column).

The new VirtuosoParameter object.

Adds a VirtuosoParameter to the VirtuosoParameterCollection with the specified parameter name, data type, parameter size, and source column name.

public VirtuosoParameter Add( string  parameterName ,
                              VirtDbType  dbType ,
                              int  size ,
                              string  sourceColumn );
parameterName

The name of the parameter.

value

One of the VirtDbType values.

size

The size of the parameter (width of the column).

sourceColumn

The name of the source column.

The new VirtuosoParameter object.

Removes all items from the collection.

public void Clear();

IList.Clear

Gets a value indicating whether a VirtuosoParameter object exists in the collection.

public bool Contains( object  value );
value

The value of the VirtuosoParameter object to find.

true if the collection contains the VirtuosoParameter; otherwise, false .

IList.Contains

Gets a value indicating whether a VirtuosoParameter object with the specified parameter name exists in the collection.

public bool Contains( string  parameterName );
parameterName

The name of the VirtuosoParameter object to find.

true if the collection contains the VirtuosoParameter; otherwise, false .

IDataParameterCollection.Contains

Copies VirtuosoParameter objects from the VirtuosoParameterCollection to the specified array.

public void CopyTo( Array  array ,
                    int  index );
array

The array into which to copy the VirtuosoParameter objects.

index

The starting index of the array.

ICollection.CopyTo

This member supports the Microsoft® .NET Framework infrastructure and is not intended to be used directly from your code.

public IEnumerator GetEnumerator();

Gets the location in the collection of a VirtuosoParameter object.

public int IndexOf( object  value );
value

The VirtuosoParameter object to find.

The zero-based location of the VirtuosoParameter in the collection.

IList.IndexOf

Gets the location in the collection of the VirtuosoParameter object with the specified parameter name.

public int IndexOf( string  parameterName );
parameterName

The name of the VirtuosoParameter object to find.

The zero-based location of the VirtuosoParameter in the collection.

IDataParameterCollection.IndexOf

Inserts a VirtuosoParameter into the collection at the specified index.

public void Insert( int  index ,
                    object  value );
index

The zero-based index where the parameter is to be inserted within the collection.

value

The VirtuosoParameter to add to the collection.

IList.Insert

Removes the specified VirtuosoParameter from the collection.

public void Remove( object  value );
value

The VirtuosoParameter object to remove from the collection.

IList.Remove

Removes the VirtuosoParameter at the specified index from the collection.

public void RemoveAt( int  index );
index

The zero-based index of the parameter to remove.

IList.RemoveAt

Removes the VirtuosoParameter with the specified name from the collection.

public void RemoveAt( string  parameterName );
parameterName

The name of the parameter to remove.

IDataParameterCollection.RemoveAt

Provides the capability for the Virtuoso .NET Data Provider to ensure that a user has a security level adequate to access a data source. This class cannot be inherited.

System.Object
System.Security.CodeAccessPermission
VirtuosoPermission
 
              public 
              sealed 
              class 
              VirtuosoPermission
             extends, 
              CodeAccessPermission
            
implements, IUnrestrictedPermission {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

Initializes a new instance of the VirtuosoPermission class.

public VirtuosoPermission();

Initializes a new instance of the VirtuosoPermission class.

public VirtuosoPermission( PermissionState  state );
state

One of the System.Security.Permissions.PermissionState values.

Creates and returns an identical copy of the current permission object.

public override IPermission Copy();

A copy of the current permission object.

IPermission.Copy

A copy of a permission object represents the same access to resources as the original permission object.

Reconstructs a security object with a specified state from an XML encoding.

public override void FromXml( SecurityElement  securityElement );
securityElement

The XML encoding to use to reconstruct the security object.

ISecurityEncodable.FromXml

Returns a new permission object representing the intersection of the current permission object and the specified permission object.

public override IPermission Intersect( IPermission  target );
target

A permission object to intersect with the current permission object. It must be of the same type as the current permission object.

A new permission object that represents the intersection of the current permission object and the specified permission object. This new permission object is a null reference (Nothing in Visual Basic) if the intersection is empty.

IPermission.Intersect

The intersection of two permissions is a permission that describes the set of operations they both describe in common. Only a demand that passes both original permissions will pass the intersection.

Returns a value indicating whether the current permission object is a subset of the specified permission object.

public override bool IsSubsetOf( IPermission  target );
target

A permission object that is to be tested for the subset relationship. This object must be of the same type as the current permission object.

true if the current permission object is a subset of the specified permission object; otherwise false .

IPermission.IsSubsetOf

The current permission object is a subset of the specified permission object if the current permission object specifies a set of operations that is wholly contained by the specified permission object. For example, a permission that represents access to C:\example.txt is a subset of a permission that represents access to C:\. If this method returns true, the current permission object represents no more access to the protected resource than does the specified permission object.

Returns a value indicating whether the permission can be represented as unrestricted without any knowledge of the permission semantics.

public bool IsUnrestricted();

true if the VirtuosoPermission instance was created with PermissionState.Unrestricted; otherwise, false .

IUnrestrictedPermission.IsUnrestricted

Creates an XML encoding of the security object and its current state.

public override SecurityElement ToXml();

An XML encoding of the security object, including any state information.

ISecurityEncodable.ToXml

Creates a permission that is the union of the permission and the specified permission.

public override IPermission Union( IPermission  target );
target

A permission to combine with the current permission. It must be of the same type as the current permission.

A new permission that represents the union of the current permission and the specified permission.

The result of a call to Union is a permission that represents all the operations represented by both the current permission and the specified permission. Any demand that passes either permission passes their union.

Allows security actions for VirtuosoPermission to be applied to code using declarative security. This class cannot be inherited.

System.Object
System.Attribute
System.Security.Permissions.SecurityAttribute
System.Security.Permissions.CodeAccessSecurityAttribute
VirtuosoPermissionAttribute
 
              public 
              sealed 
              class 
              VirtuosoPermissionAttribute
             extends, 
              CodeAccessSecurityAttribute
             {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

Initializes a new instance of the VirtuosoPermissionAttribute class.

public VirtuosoPermissionAttribute();
action

One of the SecurityAction values representing an action that can be performed using declarative security.

Returns a VirtuosoPermission object that is configured according to the attribute properties.

public override IPermission CreatePermission();

A VirtuosoPermission object.

Provides data for the RowUpdated event. This class cannot be inherited.

System.Object
System.EventArgs
System.Data.Common.RowUpdatedEventArgs
VirtuosoRowUpdatedEventArgs
 
              public 
              sealed 
              class 
              VirtuosoRowUpdatedEventArgs
             extends, 
              RowUpdatedEventArgs
             {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

Initializes a new instance of the VirtuosoRowUpdatedEventArgs class.

public VirtuosoRowUpdatedEventArgs( DataRow  row ,
                                    IDbCommand  command ,
                                    StatementType  statementType ,
                                    DataTableMapping  tableMapping );
row

The DataRow sent through an Update.

command

The IDbCommand executed when Update is called.

statementType

One of the StatementType values that specifies the type of query executed.

tableMapping

The DataTableMapping sent through an Update.

Gets the VirtuosoCommand executed when Update is called.

public  new  VirtuosoCommand  Command  ;

The VirtuosoCommand executed when Update is called.

Represents the method that will handle the RowUpdated event of a VirtuosoDataAdapter.

public delegate void VirtuosoRowUpdatedEventHandler( object  sender ,
                                                     VirtuosoRowUpdatedEventArgs  e );

The declaration of your event handler must have the same parameters as the VirtuosoRowUpdatedEventHandler delegate declaration.

sender

The source of the event.

e

A VirtuosoRowUpdatedEventArgs object that contains the event data.

The handler is not required perform any action, and your code should avoid generating exceptions or allowing exceptions to propagate to the calling method. Any exceptions that do reach the caller are ignored. When you create a VirtuosoRowUpdatedEventHandler delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event handler delegates, see "Events and Delegates" in the .NET Framework SDK documentation.

Provides data for the RowUpdating event. This class cannot be inherited.

System.Object
System.EventArgs
System.Data.Common.RowUpdatingEventArgs
VirtuosoRowUpdatingEventArgs
 
              public 
              sealed 
              class 
              VirtuosoRowUpdatingEventArgs
             extends, 
              RowUpdatingEventArgs
             {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

Initializes a new instance of the VirtuosoRowUpdatingEventArgs class.

public VirtuosoRowUpdatingEventArgs( DataRow  row ,
                                     IDbCommand  command ,
                                     StatementType  statementType ,
                                     DataTableMapping  tableMapping );
row

The DataRow sent through an Update.

command

The IDbCommand executed when Update is called.

statementType

One of the StatementType values that specifies the type of query executed.

tableMapping

The DataTableMapping sent through an Update.

Gets or sets the VirtuosoCommand executed when Update is called.

public  new  VirtuosoCommand  Command  ;

The VirtuosoCommand executed when Update is called.

Represents the method that will handle the RowUpdating event of a VirtuosoDataAdapter.

public delegate void VirtuosoRowUpdatingEventHandler( object  sender ,
                                                      VirtuosoRowUpdatingEventArgs  e );

The declaration of your event handler must have the same parameters as the VirtuosoRowUpdatingEventHandler delegate declaration.

sender

The source of the event.

e

A VirtuosoRowUpdatingEventArgs object that contains the event data.

The handler is not required perform any action, and your code should avoid generating exceptions or allowing exceptions to propagate to the calling method. Any exceptions that do reach the caller are ignored. When you create a VirtuosoRowUpdatingEventHandler delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event handler delegates, see "Events and Delegates" in the .NET Framework SDK documentation.

Represents a transaction to be made at a Virtuoso database. This class cannot be inherited.

System.Object
System.MarshalByRefObject
VirtuosoTransaction
 
              public 
              sealed 
              class 
              VirtuosoTransaction
             extends, 
              MarshalByRefObject
            
implements, IDbTransaction , IDisposable {
}

Any public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Any instance members are not guaranteed to be thread safe.

The application creates a VirtuosoTransaction object by calling BeginTransaction on the VirtuosoConnection object. All subsequent operations associated with the transaction (for example, committing or aborting the transaction), are performed on the VirtuosoTransaction object.

Gets the VirtuosoConnection object associated with the transaction.

public  VirtuosoConnection  Connection  ;

The VirtuosoConnection object to associate with the transaction.

A single application may have multiple database connections, each with zero or more transactions. This property enables you to determine the connection object associated with a particular transaction.

Specifies the IsolationLevel for this transaction

public  IsolationLevel  IsolationLevel  ;

The IsolationLevel for this transaction.

IDbTransaction.IsolationLevel

Parallel transactions are not supported. Therefore, the IsolationLevel applies to the entire transaction.

Commits the database transaction.

public void Commit();

Releases the unmanaged resources used by the VirtuosoTransaction and optionally releases the managed resources.

public void Dispose();

IDisposable.Dispose

Rolls back a transaction from a pending state.

public void Rollback();

IDbTransaction.Rollback

The transaction can be rolled back only from a pending state (after BeginTransaction has been called, but before Commit is called).