Unable to wrap a simple CTE in plpgsql loop
For a test database, I would like to create a bunch of test users (all with "default" values). There is a table called users
, and another called user_properties
. For each test user, I need to make corresponding entries in both these tables. I already have a nicely working CTE to do this, but I am unable to wrap this CTE in a loop.
CREATE OR REPLACE FUNCTION ins()
returns void as
$BODY$
BEGIN
--RETURN record;
FOR Loopid IN 0..10 LOOP
with
user as (
insert into user
values(default)
returning id
)
,user_property as (
insert into user_property (property_of)
select id from user
returning id
)
select id from user_property;
END LOOP;
END;
$BODY$
LANGUAGE 'plpgsql' VOLATILE;
It creates the function, but on running it complains
ERROR: query has no destination for result data
HINT: If you want to discard the results of a SELECT, use PERFORM instead.
But it doesn't seem possible to replace the last select
of the CTE with a perform
instead - that's a syntax error. So how can I do this?
The few questions (example) which have very similar titles have their answer that a loop/cte isn't really necessary, so they don't help me. Unless there's a very creative way of doing the exact same thing 10 times without a loop :-)
postgresql plpgsql cte
add a comment |
For a test database, I would like to create a bunch of test users (all with "default" values). There is a table called users
, and another called user_properties
. For each test user, I need to make corresponding entries in both these tables. I already have a nicely working CTE to do this, but I am unable to wrap this CTE in a loop.
CREATE OR REPLACE FUNCTION ins()
returns void as
$BODY$
BEGIN
--RETURN record;
FOR Loopid IN 0..10 LOOP
with
user as (
insert into user
values(default)
returning id
)
,user_property as (
insert into user_property (property_of)
select id from user
returning id
)
select id from user_property;
END LOOP;
END;
$BODY$
LANGUAGE 'plpgsql' VOLATILE;
It creates the function, but on running it complains
ERROR: query has no destination for result data
HINT: If you want to discard the results of a SELECT, use PERFORM instead.
But it doesn't seem possible to replace the last select
of the CTE with a perform
instead - that's a syntax error. So how can I do this?
The few questions (example) which have very similar titles have their answer that a loop/cte isn't really necessary, so they don't help me. Unless there's a very creative way of doing the exact same thing 10 times without a loop :-)
postgresql plpgsql cte
add a comment |
For a test database, I would like to create a bunch of test users (all with "default" values). There is a table called users
, and another called user_properties
. For each test user, I need to make corresponding entries in both these tables. I already have a nicely working CTE to do this, but I am unable to wrap this CTE in a loop.
CREATE OR REPLACE FUNCTION ins()
returns void as
$BODY$
BEGIN
--RETURN record;
FOR Loopid IN 0..10 LOOP
with
user as (
insert into user
values(default)
returning id
)
,user_property as (
insert into user_property (property_of)
select id from user
returning id
)
select id from user_property;
END LOOP;
END;
$BODY$
LANGUAGE 'plpgsql' VOLATILE;
It creates the function, but on running it complains
ERROR: query has no destination for result data
HINT: If you want to discard the results of a SELECT, use PERFORM instead.
But it doesn't seem possible to replace the last select
of the CTE with a perform
instead - that's a syntax error. So how can I do this?
The few questions (example) which have very similar titles have their answer that a loop/cte isn't really necessary, so they don't help me. Unless there's a very creative way of doing the exact same thing 10 times without a loop :-)
postgresql plpgsql cte
For a test database, I would like to create a bunch of test users (all with "default" values). There is a table called users
, and another called user_properties
. For each test user, I need to make corresponding entries in both these tables. I already have a nicely working CTE to do this, but I am unable to wrap this CTE in a loop.
CREATE OR REPLACE FUNCTION ins()
returns void as
$BODY$
BEGIN
--RETURN record;
FOR Loopid IN 0..10 LOOP
with
user as (
insert into user
values(default)
returning id
)
,user_property as (
insert into user_property (property_of)
select id from user
returning id
)
select id from user_property;
END LOOP;
END;
$BODY$
LANGUAGE 'plpgsql' VOLATILE;
It creates the function, but on running it complains
ERROR: query has no destination for result data
HINT: If you want to discard the results of a SELECT, use PERFORM instead.
But it doesn't seem possible to replace the last select
of the CTE with a perform
instead - that's a syntax error. So how can I do this?
The few questions (example) which have very similar titles have their answer that a loop/cte isn't really necessary, so they don't help me. Unless there's a very creative way of doing the exact same thing 10 times without a loop :-)
postgresql plpgsql cte
postgresql plpgsql cte
asked 2 mins ago
YogeschYogesch
312210
312210
add a comment |
add a comment |
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