When the Integration Service processes an SQL transformation, it runs SQL queries midstream in the pipeline. When a SELECT query retrieves database rows, the SQL transformation returns the database columns in the output ports. For other types of queries, the SQL transformation returns query results, pass-through data, or database errors in output ports.
The SQL transformation configured to run in script mode always returns one row for each input row. A SQL transformation that runs in query mode can return a different number of rows for each input row. The number of rows the SQL transformation returns is based on the type of query it runs and the success of the query.
You can view a log of the SQL query that the Integration Service passes to the database for processing. When you set logging to verbose, the Integration Service writes each SQL query to the session log. Set logging to verbose when you need to debug a session with the SQL transformation.
You can use transaction control with the SQL transformation when you configure the transformation to use a static database connection. You can also issue commit and rollback statements in the query.
The SQL transformation provides some database connection resiliency. It provides resilience for database deadlocks.