undefined_column Undefined Column — SQLSTATE 42703

A referenced column does not exist.

• The error is written to the server log and returned to the client carrying SQLSTATE 42703.
• Any driver (libpq, JDBC, psycopg, npgsql, pgx) surfaces this code in its error object so you can branch on it programmatically.
• PL/pgSQL can trap it by name: EXCEPTION WHEN undefined_column THEN.

Severity: ERROR  |  PostgreSQL versions: 12, 13, 14, 15, 16, 17

Reproduce with the exact statement and read the full message in the server log (raise log_min_messages / set log_min_error_statement for more context).

The column name is wrong, mis-cased, or not in scope at that point in the query.

Common causes:

• A typo or wrong case — PostgreSQL folds unquoted names to lowercase.
• The column was dropped or renamed.
• A missing table alias.
• Selecting a column not exposed by a subquery or CTE.

Steps to resolve 42703:

1. Verify the exact name with \d tablename in psql.
2. Match case and quoting — names with uppercase letters must be double-quoted to preserve case.
3. Qualify the column with the correct table or alias.

Reference: PostgreSQL error codes — Class 42 (Syntax Error or Access Rule Violation).