How to pass array of values to a pgplsql function

Started by Curtis Scheerover 19 years ago4 messagesgeneral
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#1Curtis Scheer
Curtis@DAYCOS.com

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

#2Erik Jones
erik@myemma.com
In reply to: Curtis Scheer (#1)
Re: How to pass array of values to a pgplsql function

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)

#3Erik Jones
erik@myemma.com
In reply to: Erik Jones (#2)
Re: How to pass array of values to a pgplsql function

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)

#4Curtis Scheer
Curtis@DAYCOS.com
In reply to: Erik Jones (#3)
Re: How to pass array of values to a pgplsql function

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)---------------------------

Show quoted text

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.