Question

We have a problem with our software and in order to correct the issue, I have to write a stored procedure that will be run as part of the upgrade process for upgrade installs. This stored procedure needs to find every row in a particular table that matches certain conditions and update that row. For internal reasons, the update has to be done through a stored procedure we wrote specifically for inserting and updating data.

Here is the stored procedure I have written to fix this issue:

CREATE OR REPLACE FUNCTION FixDataProblem() RETURNS VOID AS $$
DECLARE
    FixCursor   NO SCROLL CURSOR FOR
        SELECT * FROM MyTable WHERE ProblemColumn IN ( '?', 'PR' );
    RowToUpdate         MyTable%ROWTYPE;
BEGIN
    -- Open the cursor
    OPEN FixCursor;

    -- Start a loop
    LOOP
        -- Fetch the next row from thr cursor
        FETCH FixCursor INTO RowToUpdate;

        -- Did we get anything back?
        IF RowToUpdate IS NULL THEN
            -- We didn't. Exit the loop
            EXIT;
        END IF;

        -- Call the UpsertMyTable stored procedure to set the ProblemColumn column to NULL
        SELECT CarSystem.UpsertMyTable( RowToUpdate.RowId,
                               RowToUpdate.ForeignId,
                               RowToUpdate.CountryId,
                               NULL,
                               RowToUpdate.Plate,
                               RowToUpdate.HashedData,
                               RowToUpdate.PlateClassId,
                               RowToUpdate.AlarmClassId,
                               RowToUpdate.BeginDate,
                               RowToUpdate.EndDate,
                               RowToUpdate.ListPriorityId,
                               RowToUpdate.VehicleTypeId,
                               RowToUpdate.MakeId,
                               RowToUpdate.ModelId,
                               RowToUpdate.Year,
                               RowToUpdate.ColorId,
                               RowToUpdate.Notes,
                               RowToUpdate.OfficerNotes,
                               NULL,
                               UUID_GENERATE_V4() );
    END LOOP;

    -- Close the cursor
    CLOSE ListDetailsCursor;
END;
$$ LANGUAGE plpgsql;

This stored procedure fine, but when I run it, I get:

ERROR:  query has no destination for result data
HINT:  If you want to discard the results of a SELECT, use PERFORM instead.
CONTEXT:  PL/pgSQL function "fixdataproblem" line 22 at SQL statement


********** Error **********

ERROR: query has no destination for result data
SQL state: 42601
Hint: If you want to discard the results of a SELECT, use PERFORM instead.
Context: PL/pgSQL function "fixdataproblem" line 22 at SQL statement

How do I fix this issue? I believe I am calling the stored procedure correctly. I really don’t know what the issue with this stored procedure is.

Thanks

Tony

Answer 1

It says right there:

ERROR:  query has no destination for result data
HINT:  If you want to discard the results of a SELECT, use PERFORM instead.
CONTEXT:  PL/pgSQL function "fixdataproblem" line 22 at SQL statement

And on line 22:

    -- Call the UpsertMyTable stored procedure to set the ProblemColumn column to NULL
    SELECT CarSystem.UpsertMyTable( RowToUpdate.RowId,
    ...

Change it from SELECT to PERFORM. See PERFORM for why.