Sanity check on view

Hi,

I've got a view, which is supposed to be called with a WHERE clause, like:

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SELECT * FROM data_view WHERE od_id = '1234';
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I'd like to make sure it is called correctly: not all "od_id" values should be permitted.

I came up with this solution:

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--  FUNCTION: get_data_view
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CREATE OR REPLACE FUNCTION get_data_view(integer)
  RETURNS SETOF data_view AS
'
  DECLARE

    data    RECORD;

  BEGIN

    FOR data IN SELECT * FROM data_view WHERE od_id = $1 LOOP

      IF data.foo != ''bar'' THEN
        RAISE EXCEPTION ''blablabla'';
      END IF;

      RETURN NEXT data;
    END LOOP;

    RETURN;

  END;
'
  LANGUAGE 'plpgsql' VOLATILE;
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Is there maybe a better alternative?

I tried to raise an exception from sql directly, in a "case... when...", but it didn’t work...

Thanks!

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