Output buffer

More read-only database operations can make use of query parallelism.

To consistently enable parallelism for read-only operations, Swarm64 DA adds a S64 DA Output Buffer node on top of the query plan. This node enables query parallelism in more cases, such as cursors, materialized views, cursors within functions, and database connectors like JDBC. If the S64 DA Output Buffer node is not required to enable parallelism it is bypassed and thereby does not influence query runtime. The S64 DA Output Buffer node also replaces any Materialize node that would appear in the top of the plan.

Restriction:

Avoid using cursors in conjunction with DELETE/UPDATE ... CURRENT OF my_cursor statements and follow the advise in the EPAS documentation.

The S64 DA Output Buffer is incompatible with CURRENT OF and errors out accordingly. If a query stopped working because of output buffering and you cannot declare your cursor FOR UPDATE, consider disabling the feature when executing that query.

Settings

swarm64da.enable_outputbuffer (boolean)

Enables or disables the output buffer node. The default is on.