SQL Query Rewrite Facility Options

The SQL query rewrite facility is enabled by default in SPD Server. When an SPD Server user submits SQL statements that contain subexpressions that SPD Server can handle more efficiently by using the SQL query rewrite facility, the software optimizes the SQL query. The following RESET options provide control over the SQL query Rewrite Facility.

_QRWENABLE Option

_QRW Option

_QRWENABLE Option

Use the _QRWENABLE reset option to disable the SQL query rewrite facility. You might use this option if you suspect that the SQL query rewrite facility is not enhancing the performance of the SQL query execution. The SQL query rewrite facility is enabled by default.

Examples:

Disable SQL query rewrite facility:

execute(reset no_qrwenable) by sasspds; /* Disable query rewrite */
execute(reset _qrwenable=0) by sasspds; /* Another way to disable */

Re-enable SQL query rewrite facility:

execute(reset _qrwenable) by sasspds; /* Re-enable query rewrite */
execute(reset _qrwenable=1) by sasspds; /* Another way to enable */

_QRW Option

Use the _QRW reset option to enable diagnostic debugging and tracing outputs from the SQL query rewrite facility in the log. The diagnostic debugging option is disabled by default.

Examples:

Enable diagnostic debugging function:

execute(reset _qrw) by sasspds; /* Enable diagnostics */
execute(reset _qrw=1) by sasspds; /* Another way to enable */

Disable diagnostic debugging function:

execute(reset no_qrw) by sasspds; /* Disable diagnostics */
execute(reset _qrw=0) by sasspds; /* Another way to disable */

Last updated: February 3, 2017