Permanently Attach a Comment to a Query: Quick Tip

Jim Knicely authored this tip.

There are several system tables like QUERY_REQUESTS that store the queries executed in the database. To help understand why a query was executed (i.e., for debugging purposes), you might want to add a comment to the SQL code.

Example: dbadmin=> /* This is a SELECT from the table JIM */ dbadmin-> SELECT * FROM jim; c --- 1 (1 row) dbadmin=> SELECT request FROM query_requests WHERE transaction_id = current_trans_id() AND statement_id = current_statement() - 1; request -------------------- SELECT * FROM jim; (1 row) What happened to the comment?

If you’d like to “glue” the comment to the query permanently, use a “nested” comment:

dbadmin=> SELECT /* This is a SELECT from the table JIM */ * FROM jim; c --- 1 (1 row) dbadmin=> SELECT request FROM query_requests WHERE transaction_id = current_trans_id() AND statement_id = current_statement() - 1; request -------------------------------------------------------------- SELECT /* This is a SELECT from the table JIM */ * FROM jim; (1 row) Have fun!