builtins: make extract work with TimeTZ

[otan]

Refs: #26097

Add extract for TimeTZ, which has a slight extension to that of Time and
a gotcha in epoch.

No release note as this will be combined in a later PR.

Release note: none

[cockroach-teamcity]

This change is 

[solongordon]

I messed around a bit with Postgres and it seems like you should not be forcing all values to be positive:

solon=# select extract('timezone_hour' from '00:00-01:02'::TIMETZ);
 date_part
-----------
        -1
(1 row)

solon=# select extract('timezone_minute' from '00:00-01:02'::TIMETZ);
 date_part
-----------
        -2
(1 row)

solon=# select extract('timezone' from '00:00-01:02'::TIMETZ);
 date_part
-----------
     -3720
(1 row)

Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @solongordon)

[otan]

I messed around a bit with Postgres and it seems like you should not be forcing all values to be positive:

WEIRD i swear it didn't work... maybe i typed something else by accident..

[otan]

oh.... i tested timestamptz....

otan=# select extract('timezone' from '2001-01-01 11:00+06:00'::timestamptz);
 date_part
-----------
     21600
(1 row)

otan=# select extract('timezone' from '2001-01-01 11:00-06:00'::timestamptz);
 date_part
-----------
     21600
(1 row)

otan=# select extract('timezone' from '2001-01-01 11:00+06:00'::timestamptz);
 date_part
-----------
     21600
(1 row)

[otan]

oh it's even more subtle than that, for timestamp tz it's always where you are when you extract

[solongordon]

modulo one documentation nit.

Reviewed 1 of 4 files at r1.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @otan and @solongordon)

---

pkg/sql/sem/builtins/builtins.go, line 1835 at r1 (raw file):

			},
			Info: "Extracts `element` from `input`.\n\n" +
				"Compatible elements: hour, minute, second, millisecond, microsecond, epoch\n" +

Minor: Missing , after epoch.

[otan]

bors r+

[craig]

Build failed (retrying...)

• GitHub CI (Cockroach)

[craig]

Build succeeded

• GitHub CI (Cockroach)