Attempting to DROP or ALTER a table while another session holds a lock on it. Long-running query on a table preventing a schema migration. Autovacuum running on the table during a maintenance window

Step 1: Find blocking sessions: `SELECT pid, query, state FROM pg_stat_activity WHERE wait_event_type='Lock';`. Step 2: Terminate the blocking session if safe: `SELECT pg_terminate_backend( );`. Step 3: Use `LOCK TIMEOUT` to avoid waiting indefinitely: `SET lock_timeout = '5s';`. Step 4: Schedule schema migrations during low-traffic windows.

Medium severityconfiguration

Power BI Refresh Error:
55006

What does this error mean?

The operation cannot be performed because the target object is currently in use by another session.

Common causes

1Attempting to DROP or ALTER a table while another session holds a lock on it
2Long-running query on a table preventing a schema migration
3Autovacuum running on the table during a maintenance window

How to fix it

1Step 1: Find blocking sessions: `SELECT pid, query, state FROM pg_stat_activity WHERE wait_event_type='Lock';`
2Step 2: Terminate the blocking session if safe: `SELECT pg_terminate_backend(<pid>);`
3Step 3: Use `LOCK TIMEOUT` to avoid waiting indefinitely: `SET lock_timeout = '5s';`
4Step 4: Schedule schema migrations during low-traffic windows.

Frequently asked questions

How do I prevent 55006 errors in automated pipelines?

Add retry logic with exponential backoff, validate data quality before loading, and monitor pipeline failures in MetricSign to catch this error early.

Official documentation: https://www.postgresql.org/docs/current/errcodes-appendix.html