domain type with create cast not working on pg15, but work on pg14
seems like a bug, since PostgreSQL 15 - pgPedia - a PostgreSQL Encyclopedia
<https://pgpedia.info/postgresql-versions/postgresql-15.html> does not
mention anything about domain/cast changes.
the following code works on
PostgreSQL 15devel (Ubuntu
15~~devel~20220407.0430-1~713.git79b716c.pgdg20.04+1) on
x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 9.4.0-1ubuntu1~20.04.1) 9.4.0,
64-bit
---
create domain isodow as integer check(value between 1 and 7);
create function testcast(in a timestamptz ,out isodow)
as $$ select extract(dow from a ) $$ language sql;
CREATE CAST (timestamptz AS isodow) WITH FUNCTION testcast(timestamptz) AS
ASSIGNMENT;
----
then execute it:
select '2022-04-23 19:00:01 +5:30'::timestamptz::isodow;
return *6*
*---*
however when i run it PostgreSQL 14.2 (Ubuntu 14.2-1.pgdg20.04+1+b1) on
x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 9.4.0-1ubuntu1~20.04.1) 9.4.0,
64-bit
yield the following error:
Show quoted text
ERROR: 42846: cannot cast type timestamp with time zone to isodow
LINE 1: select '2022-04-23 19:00:01 +5:30'::timestamptz::isodow;
^
LOCATION: transformTypeCast, parse_expr.c:2652
alias <postgres.rocks@gmail.com> writes:
create domain isodow as integer check(value between 1 and 7);
create function testcast(in a timestamptz ,out isodow)
as $$ select extract(dow from a ) $$ language sql;
CREATE CAST (timestamptz AS isodow) WITH FUNCTION testcast(timestamptz) AS
ASSIGNMENT;
For me, on either v14 or v15 that draws an informative warning:
WARNING: cast will be ignored because the target data type is a domain
and that makes it unsurprising that this fails:
=# select '2022-04-23 19:00:01 +5:30'::timestamptz::isodow;
ERROR: cannot cast type timestamp with time zone to isodow
LINE 1: select '2022-04-23 19:00:01 +5:30'::timestamptz::isodow;
^
I don't see any difference in behavior between v13, v14, v15
on this. The test case fails outright before v13, because
older versions wouldn't do the implied cast here:
=# create function testcast(in a timestamptz ,out isodow)
as $$ select extract(dow from a ) $$ language sql;
ERROR: return type mismatch in function declared to return isodow
DETAIL: Actual return type is double precision.
CONTEXT: SQL function "testcast"
but with that corrected, the warning appears at least back to v10.
regards, tom lane