How to fix Raise exception in PostgreSQL

PostgreSQLINTERMEDIATEMEDIUMUpdated Dec 28, 2025· 254 views

RAISE EXCEPTION is a PL/pgSQL statement for throwing custom errors in stored procedures and functions. Understanding proper syntax and usage prevents compilation errors and ensures transactions abort correctly when validation fails.

Quick fix

Fixes Raise exception

-- Correct: 2 placeholders, 2 arguments
RAISE EXCEPTION 'User % not found with status %', user_id, status;

-- Wrong: 2 placeholders, 1 argument
RAISE EXCEPTION 'User % not found with status %', user_id;
  1. Verify RAISE syntax and format string placeholders
  2. Ensure RAISE is inside a PL/pgSQL block
  3. Use correct USING clause syntax for additional options
  4. Verify SQLSTATE code format when using custom codes
postgresql — error
-- Correct: 2 placeholders, 2 arguments
RAISE EXCEPTION 'User % not found with status %', user_id, status;
-- Wrong: 2 placeholders, 1 argument
RAISE EXCEPTION 'User % not found with status %', user_id;
Raise exception

What this error means

In PostgreSQL's PL/pgSQL procedural language, RAISE EXCEPTION is a statement that throws a custom error message and aborts the current transaction. When you encounter "Raise exception" errors, it typically means either a syntax error in your RAISE statement, incorrect format string placeholders, or a misuse of the RAISE statement outside of a PL/pgSQL context. RAISE can report messages at different severity levels (DEBUG, LOG, INFO, NOTICE, WARNING, EXCEPTION), with EXCEPTION being the default level that terminates execution.

Typical symptoms

  • Syntax error when defining functions with RAISE statements
  • Number of format string placeholders does not match the number of arguments
  • RAISE statement used outside of a PL/pgSQL function or stored procedure
  • Incorrect SQLSTATE or error code format
  • Missing quotes around the error message

Common causes

  1. Mismatch between % placeholders in the format string and the number of arguments provided
  2. Using RAISE outside of a PL/pgSQL block (RAISE is only valid in functions, procedures, and BEGIN...END blocks)
  3. Incorrect syntax for USING clause options (MESSAGE, DETAIL, HINT, ERRCODE)
  4. Attempting to use RAISE with an empty argument list outside of exception handling
  5. Invalid SQLSTATE code format (must be 5 characters)

How to fix "Raise exception"

1Verify RAISE syntax and format string placeholders

Ensure the number of % placeholders in your format string matches the number of arguments. Each % will be replaced by the next argument value.

sql
-- Correct: 2 placeholders, 2 arguments
RAISE EXCEPTION 'User % not found with status %', user_id, status;

-- Wrong: 2 placeholders, 1 argument
RAISE EXCEPTION 'User % not found with status %', user_id;
2Ensure RAISE is inside a PL/pgSQL block

RAISE statements are only valid within PL/pgSQL functions, stored procedures, and BEGIN...END blocks. They cannot be used in regular SQL queries.

sql
-- Correct: Inside a function
CREATE OR REPLACE FUNCTION check_user(user_id INT)
RETURNS VOID AS $$
BEGIN
    IF NOT EXISTS (SELECT 1 FROM users WHERE id = user_id) THEN
        RAISE EXCEPTION 'User % does not exist', user_id;
    END IF;
END;
$$ LANGUAGE plpgsql;

-- Wrong: Direct use in SQL
RAISE EXCEPTION 'Invalid input'; -- Will fail
3Use correct USING clause syntax for additional options

When providing error details, hints, or custom error codes, use the USING clause with proper syntax.

sql
-- Correct: USING clause with multiple options
RAISE EXCEPTION 'Duplicate user ID: %', user_id
    USING HINT = 'Please provide a unique user ID',
          ERRCODE = 'unique_violation';

-- Wrong: Missing USING keyword
RAISE EXCEPTION 'Invalid input'
    HINT = 'Check your parameters';
4Verify SQLSTATE code format when using custom codes

If using custom SQLSTATE/ERRCODE, ensure the code is exactly 5 characters. PostgreSQL provides standard codes, but custom codes should start with a letter (typically 'A') followed by three digits.

sql
-- Correct: Using standard SQLSTATE
RAISE EXCEPTION 'Invalid age' USING ERRCODE = '22003';

-- Correct: Using custom error code
RAISE EXCEPTION 'Business logic error' USING ERRCODE = 'A0001';

-- Wrong: Invalid format
RAISE EXCEPTION 'Error' USING ERRCODE = 'INVALID';
5Handle re-raising exceptions in exception blocks

Inside an EXCEPTION clause, you can use bare RAISE (with no arguments) to re-throw the caught exception.

sql
CREATE OR REPLACE FUNCTION safe_operation()
RETURNS VOID AS $$
BEGIN
    -- Some operation that might fail
    PERFORM * FROM invalid_table;
EXCEPTION
    WHEN undefined_table THEN
        -- Re-throw the same error
        RAISE;
END;
$$ LANGUAGE plpgsql;

Advanced notes

The RAISE statement can reference PostgreSQL's predefined condition names (like unique_violation, division_by_zero, etc.) or custom SQLSTATE codes. When no condition or SQLSTATE is specified, the default error code is RAISE_EXCEPTION (P0001). Transaction behavior is important: RAISE EXCEPTION will roll back the entire transaction, while other levels (NOTICE, WARNING) only report messages. For trigger functions, consider whether you want to abort the operation (EXCEPTION) or just warn (WARNING). In production code, always include meaningful HINT and DETAIL options to help developers debug issues.

Frequently asked questions

What does "Raise exception" mean?
In PostgreSQL's PL/pgSQL procedural language, RAISE EXCEPTION is a statement that throws a custom error message and aborts the current transaction. When you encounter "Raise exception" errors, it typically means either a syntax error in your RAISE statement, incorrect format string placeholders, or a misuse of the RAISE statement outside of a PL/pgSQL context. RAISE can report messages at different severity levels (DEBUG, LOG, INFO, NOTICE, WARNING, EXCEPTION), with EXCEPTION being the default level that terminates execution.
How do I fix "Raise exception"?
RAISE EXCEPTION is a PL/pgSQL statement for throwing custom errors in stored procedures and functions. Understanding proper syntax and usage prevents compilation errors and ensures transactions abort correctly when validation fails.
What causes "Raise exception"?
Mismatch between % placeholders in the format string and the number of arguments provided Using RAISE outside of a PL/pgSQL block (RAISE is only valid in functions, procedures, and BEGIN...END blocks) Incorrect syntax for USING clause options (MESSAGE, DETAIL, HINT, ERRCODE)
Is the "Raise exception" error serious?
It is a medium-severity error — more of a blocker than a risk. The steps above resolve it.

Official resources & further reading