Thread: How to pass array of values to a pgplsql function

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?


Thanks,

Curtis

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)

Erik Jones wrote:
> 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.
>
Whoa, replied to this out of the General mailing list before I saw the
other answers on the SQL list...  Sorry guys

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

Thanks, Erik another possible solution would also be this.

Here it is in case you are interested.

On 7/18/06, Tony Wasson <ajwasson@gmail.com> wrote:
> On 7/18/06, Curtis Scheer <Curtis@daycos.com> 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).
> >

Ahhh... Here's an example using Tom's recommended field=ANY (arrayvalue)
SQL.


CREATE TABLE ids
(
        id      INTEGER
        , PRIMARY KEY (id)
);

INSERT INTO ids VALUES (1);
INSERT INTO ids VALUES (2);
INSERT INTO ids VALUES (3);

CREATE OR REPLACE FUNCTION example_array_input(INT[]) RETURNS SETOF ids AS
$BODY$ DECLARE
        in_clause ALIAS FOR $1;
        clause  TEXT;
        rec     RECORD;
BEGIN
        FOR rec IN SELECT id FROM ids WHERE id = ANY(in_clause)
        LOOP
                RETURN NEXT rec;
        END LOOP;
        -- final return
        RETURN;
END
$BODY$ language plpgsql;

SELECT * FROM example_array_input('{1,2,4,5,6}'::INT[]);

---------------------------(end of broadcast)---------------------------


>>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.