explain with costs in subselect.sql

Andres Freund <andres@anarazel.de> writes:

When forcing JITing to be enabled for all queries, obviously only useful
for testing, I noticed that two explain outputs changed after I added
explain support.

The only differences come from:

-- Unspecified-type literals in output columns should resolve as text

SELECT *, pg_typeof(f1) FROM
(SELECT 'foo' AS f1 FROM generate_series(1,3)) ss ORDER BY 1;

-- ... unless there's context to suggest differently

explain verbose select '42' union all select '43';
explain verbose select '42' union all select 43;

which don't use costs=off. Is there a reason for that? I assume it was
just a harmless oversight?

Duh, yeah, explain (verbose, costs off) would do fine there.
Mea culpa. Do you want to fix it?

regards, tom lane

On 2018-03-12 18:25:42 -0400, Tom Lane wrote:

Andres Freund <andres@anarazel.de> writes:

When forcing JITing to be enabled for all queries, obviously only useful
for testing, I noticed that two explain outputs changed after I added
explain support.

The only differences come from:

-- Unspecified-type literals in output columns should resolve as text

SELECT *, pg_typeof(f1) FROM
(SELECT 'foo' AS f1 FROM generate_series(1,3)) ss ORDER BY 1;

-- ... unless there's context to suggest differently

explain verbose select '42' union all select '43';
explain verbose select '42' union all select 43;

which don't use costs=off. Is there a reason for that? I assume it was
just a harmless oversight?

Duh, yeah, explain (verbose, costs off) would do fine there.
Mea culpa. Do you want to fix it?

Yup, will do.

Random aside: Noticed that we have *no* proper coverage of AND / OR
behaviour of returning NULL if no element returns true. Will push
something to add coverage, I've now manually retested that twice for
JITing, which seems stupid.

Greetings,

Andres Freund