15.5.2. Elements Description
The <sync> tag of the updategram signifies
the beginning of an operation(s) The rows specified in the
<before> refer to existing records in the
database. The rows specified in the <after>
block refer to what the user wants in the database.
<TABLENAME.../> identifies target table.
The sql:at-identity attribute stores the last
identity value added by the system (if possible). This identity value can
then be used in subsequent operations.
The sql:id attribute is used to mark rows. This
forces an association between the record specified in the
<before> and
<after> block in the update gram. When there
are multiple instances specified, it is recommended that
sql:id attribute be used for all the instances.
Each <TABLENAME.../> refers to a single
table. Multiple <TABLENAME.../> entries are
allowed in the same <before> or
<after> tags, or in both
<before> and
<after> tags; however, nesting is not
allowed. The <before> and
<after> tags are optional. A missing tag is
the same as having a tag with no content.