Question

When I have two INSERT SQL statements (see below) within a begin; and commit; transaction then the RETURNING * does not return anything but if I take out the begin; and commit; the RETURNING * does return the inserted record.
How can I get the RETURNING * to work within a transaction?

BEGIN;

INSERT INTO gis_field_configuration
   (level_unique_name, level_name_caption, use_for_charts, use_as_displayby, 
    displayby_label, data_type, level_help_text)
VALUES (
    '[john].[john]',
    'john',
    'false',
    'false',
    '',
    'text',
    'help text'
);

INSERT INTO gis_field_configuration_bycube
   (cube, level_unique_name)
VALUES (
    'Instruments',
    '[john].[john]'
) RETURNING *;

COMMIT;

Answer 1

One way would be to use a data-modifying CTE and pack the two INSERTs into one command. Requires PostgreSQL 9.1 or later:

WITH x AS (
   INSERT INTO gis_field_configuration (level_unique_name, level_name_caption
                ,use_for_charts, use_as_displayby, displayby_label, data_type
                ,level_help_text)
   VALUES (
       '[john].[john]',
       'john',
       'false',
       'false',
       '',
       'text',
       'help text'
   )
   )
INSERT INTO gis_field_configuration_bycube
   (cube, level_unique_name)
VALUES (
    'Instruments',
    '[john].[john]'
    )
RETURNING *;

However, you do get values back with RETURNING * in any case. Just read them in before sending COMMIT. Sent in as batch, only results from the last command are returned – which would be the result of COMMIT, if you send all commands as one batch.

Hold back COMMIT; until you have received the results from the second INSERT.

---

In a plpgsql function

A function runs inside a transaction automatically . You don’t need explicit BEGIN / COMMIT. To reuse values you get back from an INSERT use RETURNING *expressions* INTO [STRICT] *target*.

Consider this simple demo:

CREATE TABLE foo (foo_id serial, bar text);

CREATE OR REPLACE FUNCTION f_foo()
  RETURNS void LANGUAGE plpgsql AS
$BODY$
DECLARE
   foo_var foo; -- type name = table name, fits return type of RETURNING *
   -- or use a generic type record
BEGIN

   INSERT INTO foo (bar)
   VALUES ('baz')
   RETURNING *
   INTO foo_var;

   RAISE NOTICE 'New id is: %', foo_var.foo_id;

   -- do stuff with foo_var

   END;
   $BODY$;

SELECT f_foo();