3. ODBC Client Components

Abstract

This chapter describes the ODBC client component of OpenLink Universal Data Access (UDA).

ODBC stands for Open Database Connectivity, a data-access API implementation from Microsoft that conforms to the X/Open SQL CLI specification. ODBC links ODBC compliant applications to ODBC Drivers via the ODBC Driver Manager.

ODBC Driver Managers exist on other platforms such as Mac, Unix and Linux. These platforms usually make use of the "iODBC Driver Manager". Additional information regarding iODBC can be obtained from: www.iodbc.org.

The required parameters are configured through environment-variables - either use the web-based Administrative Assistant (normally located at <http://server:8000/>) navigating through `Server Components Administration', `Database Agent Administration', `Database Agent Settings by Form', select the name of the agent section used, and scroll to the section `OpenLink Agent Startup Parameters', or edit the rulebook file (oplrqb.ini) directly, to assert settings for the OCI_CONNPOOL_* settings below:

[Environment ORACLE90]
ORACLE_HOME        = /dbs/oracle90
ORACLE_SID         = ORCL
;ORACLE_SERVER      = T
;TWO_TASK           = P:
;ODBC_CATALOGS      = Y         ; Uncomment after loading odbccat9.sql
;MULTIPLEX_LDA      = 5         ; Allow 5 OpenLink clients on a single lda
;OPL_USR_TBLS_FIRST = Y         ; Sort SQLTables starting with user tables
SHOW_REMARKS       = N  ; Retrieve SQLColumns REMARKS field
CURSOR_SENSITIVITY = LOW        ; Set to HIGH after loading odbccat9.sql
;OCI_PREFETCH_ROWS  = 100       ; Number of rows to prefetch
;OCI_PREFETCH_MEMORY = 65535    ; Amount of memory to use for prefetching
;LD_LIBRARY_PATH = /dbs/oracle81/lib    ; Find shared libraries
;SHLIB_PATH      = /dbs/oracle81/lib    ; Find HP/UX shared libraries
;LIBPATH         = /dbs/oracle81/lib    ; Find AIX shared libraries
;NLS_LANG        = AMERICAN_AMERICA.UTF8 ; Uncomment for Unicode connections
OCI_CONNPOOL_MIN = 0         ; minimum initial connections in pool
OCI_CONNPOOL_INCR = 1        ; number of new connections when others busy
OCI_CONNPOOL_MAX = 1         ; sum of MIN+INCR
OCI_CONPOOL_WAIT = TRUE      ; whether new query waits or errors when all busy
OCI_CONNPOOL_LINGER = 0      ; seconds to linger after last connection cleared

OCI connection pooling is disabled by setting a minimum connection pool size of 0.

3. ODBC Client Components

Abstract

Table of Contents

3.7. Multi-Tier-specific Connection-Pooling

3.7.1. Multi-Tier-specific configuration