Encountered 'error: relation "table_name" does not exist'. why?

This error indicates that you're trying to access a table that doesn't exist in the current schema or at all.

Example:

ERROR:  relation "nonexistent_table" does not exist

Solution:

1. Check the table name for any typos.
2. Ensure the table exists in the current schema or specify the schema explicitly.
3. Confirm that you have the appropriate permissions.