Thread

1. BUG #19064: Trigger allows creation with invalid column references but fails at runtime

   PG Bug reporting form <noreply@postgresql.org> — 2025-09-26T07:36:24Z

   The following bug has been logged on the website:
   
   Bug reference:      19064
   Logged by:          Ketan Bhatiya
   Email address:      ketan.bhatiya@lenditt.com
   PostgreSQL version: Unsupported/Unknown
   Operating system:   Windows
   Description:        
   
   Example Function & Trigger
   
   CREATE OR REPLACE FUNCTION update_order_total()
   RETURNS TRIGGER AS $$
   BEGIN
      -- Wrong column reference: "wrong_column" does not exist in "Orders"
      UPDATE Orders
      SET total = NEW.wrong_column
      WHERE id = NEW.id;
      RETURN NULL;
   END;
   $$ LANGUAGE plpgsql;
   
   CREATE OR REPLACE TRIGGER trg_update_order_total
   AFTER UPDATE ON Orders
   FOR EACH ROW
   EXECUTE FUNCTION update_order_total();
   
   
   Steps to Reproduce
   
   Run the above function and trigger creation.
   ✅ They are created successfully.
   
   Update a row in Orders.
   
   Expected Result
   If the trigger contains a reference to a non-existing column, PostgreSQL
   should throw an error at creation time.
   
   Actual Result
   
   The function and trigger creation succeed.
   
   ❌ At runtime, when an update happens, it fails with:
   
   ERROR: record "new" has no field "wrong_column"
   
   Suggestion / Proposed Improvement
   PostgreSQL should validate column references at trigger creation time, not
   just at runtime.
   If a column does not exist in the target table (Orders in this example),
   trigger creation should fail immediately with a clear error message.
   
   

2. Re: BUG #19064: Trigger allows creation with invalid column references but fails at runtime

   David G. Johnston <david.g.johnston@gmail.com> — 2025-09-26T12:46:03Z

   On Friday, September 26, 2025, PG Bug reporting form <noreply@postgresql.org>
   wrote:
   
   > The following bug has been logged on the website:
   >
   > Bug reference:      19064
   > Logged by:          Ketan Bhatiya
   > Email address:      ketan.bhatiya@lenditt.com
   > PostgreSQL version: Unsupported/Unknown
   > Operating system:   Windows
   > Description:
   >
   > Suggestion / Proposed Improvement
   > PostgreSQL should validate column references at trigger creation time, not
   > just at runtime.
   > If a column does not exist in the target table (Orders in this example),
   > trigger creation should fail immediately with a clear error message.
   >
   >
   The bug reporting list should not be used for feature requests.  Those
   should be directed to -general.
   
   It seems unlikely anyone is going to spend time on this though.  You are
   expected to test what you write and this fails immediately and obviously.
   
   David J.
   

3. Re: BUG #19064: Trigger allows creation with invalid column references but fails at runtime

   Rahila Syed <rahilasyed90@gmail.com> — 2025-09-26T12:59:45Z

   Hi
   
   
   
   > Suggestion / Proposed Improvement
   > PostgreSQL should validate column references at trigger creation time, not
   > just at runtime.
   > If a column does not exist in the target table (Orders in this example),
   > trigger creation should fail immediately with a clear error message.
   >
   >
   This behaviour is by design in PostgreSQL. The CreateTrigger() is
   responsible
   for creating a dependency between trigger and its underlying pl/pgsql
   function.
   The pl/pgsql function is only parsed when it is executed for the first time.
   
   This approach allows for flexibility, such as adding columns to a table
   after a trigger
   has been created. On the other hand, if a column existing at the time of
   trigger creation
   is later removed, validating at creation time would not offer much
   advantage in these
   situations.
   
   Thank you,
   Rahila Syed
   

4. Re: BUG #19064: Trigger allows creation with invalid column references but fails at runtime

   Anthony Sotolongo <asotolongo@gmail.com> — 2025-09-26T13:35:50Z

   From my point of view, this extension can help detect these types of
   problems:
   
   https://github.com/okbob/plpgsql_check
   
   Regards
   
   El vie, 26 sept 2025 a las 10:00, Rahila Syed (<rahilasyed90@gmail.com>)
   escribió:
   
   > Hi
   >
   >
   >
   >> Suggestion / Proposed Improvement
   >> PostgreSQL should validate column references at trigger creation time, not
   >> just at runtime.
   >> If a column does not exist in the target table (Orders in this example),
   >> trigger creation should fail immediately with a clear error message.
   >>
   >>
   > This behaviour is by design in PostgreSQL. The CreateTrigger() is
   > responsible
   > for creating a dependency between trigger and its underlying pl/pgsql
   > function.
   > The pl/pgsql function is only parsed when it is executed for the first
   > time.
   >
   > This approach allows for flexibility, such as adding columns to a table
   > after a trigger
   > has been created. On the other hand, if a column existing at the time of
   > trigger creation
   > is later removed, validating at creation time would not offer much
   > advantage in these
   > situations.
   >
   > Thank you,
   > Rahila Syed
   >