How to Fix PostgreSQL Error 42P01 (Relation Does Not Exist)

What Is PostgreSQL Error 42P01?

Error 42P01 occurs when PostgreSQL cannot find a referenced table or relation. The message usually appears as: ERROR: relation "table_name" does not exist.

Common Causes

• Misspelled table name
• Incorrect schema
• Case-sensitive table naming
• Table not created

Example

SELECT * FROM Users;

If the table was created as "users", PostgreSQL treats it differently because of case sensitivity.

Fix

• Check schema with \dt
• Use correct schema prefix: public.users
• Avoid quoted identifiers when possible

Best Practice

Always use lowercase table names and avoid unnecessary quoting to prevent 42P01 errors.