Logs the operations that the SQL engine performs while executing a query. Operations include preparing a statement to be executed, executing the statement, and (if needed) fetching the data. These are internal operations that do not necessarily directly correlate calls made to the data source.
Message Levels
CONFIG - Any errors or warnings detected by the SQL engine are written at this level.
FINE - In addition to the same information logged by the CONFIG level, SQL engine operations are logged at this level. In particular, the SQL statement that is being executed is written at this level.
FINER - In addition to the same information logged by the CONFIG and FINE levels, data sent or received in the process of performing an operation is written at this level.