Re: How to pass array of values to a pgplsql function - Mailing list pgsql-general

From Erik Jones
Subject Re: How to pass array of values to a pgplsql function
Date
Msg-id 44BD28DC.6060306@myemma.com
Whole thread Raw
In response to How to pass array of values to a pgplsql function  (Curtis Scheer <Curtis@DAYCOS.com>)
Responses Re: How to pass array of values to a pgplsql function  (Erik Jones <erik@myemma.com>)
List pgsql-general
Curtis Scheer wrote:
> Does anyone have any examples of how I would make a stored procedure in
> plpgsql that would allow for passing a list or arrays of values to be used
> in an sql IN clause?  Like so: select * from table where field1 in (values).
> Is this possible?
>
>
Well, a good thing to note here is that there is a very distinct
semantic difference between an array in postgres and what IN clauses
take as input:  and array
is a data type whereas IN clauses take a parenthesized list of comma
separated values.  So, if you  pass an array into a function wherein
you then need
to use those values in an IN clause, you can build yourself an string of
the values in the array, comma separated of course.

e.g.

CREATE OR REPLACE FUNCTION somefunc(ids int[]) RETURNS boolean AS $sf$
DECLARE
    in_values varchar;
    good int;
BEGIN
    FOR i IN array_upper(ids, 1) LOOP
       in_values := in_values || ids[i] || ',';
    END LOOP;
    in_values := substring(in_values FROM 1 FOR
character_length(in_values) - 1); -- this will chop off the last comma

    EXECUTE 'SELECT 1 FROM blah WHERE blah.id IN (' || in_values ||');'
INTO good;
    IF(good = 1) THEN
       RETURN TRUE;
    ELSE
        RETURN FALSE;
    END IF;
END;
$sf$ LANGUAGE plpgsql;

Or, it may be easier given whatever your situation to simply use the
array as the argument to a row-wise AND or SOME expression.

--
erik jones <erik@myemma.com>
software development
emma(r)


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