sql: add support for EXECUTE SCHEDULE statement

[spilchen]

Add a new SQL statement 'EXECUTE SCHEDULE <schedule_id>' to execute a scheduled job immediately. This reuses the existing logic from ALTER BACKUP SCHEDULE ... EXECUTE IMMEDIATELY, but generalizes it to support any scheduled job.

This functionality is particularly useful for TTL jobs, allowing users to trigger them on demand.

The <schedule_id> can be a literal or a subquery (e.g., from SHOW SCHEDULES). If multiple are provided, you must use EXECUTE SCHEDULES.

Resolves: #146723
Epic: none
Release note (sql change): Added support for EXECUTE SCHEDULE <schedule_id> to allow immediate execution of a scheduled job.

[cockroach-teamcity]

This change is 

[rafiss]

i only had minor comments, this lgtm!

could you post this PR in #db-jobinfra-eng on Slack as well to check if they have any feedback?

Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @dt, @mw5h, and @spilchen)

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pkg/sql/parser/testdata/control_job line 642 at r1 (raw file):

parse
EXECUTE SCHEDULES SELECT 123

can we also verify that EXECUTE SCHEDULE SELECT 123 (the non-plural variant) parses?

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pkg/sql/parser/lexer.go line 330 at r1 (raw file):

				lval.id = FOR_JOB
			}
		case EXECUTE:

i think we need to add "execute" to the lookaheadKeywords slice:

cockroach/pkg/sql/parser/lexer.go

Line 228 in 9c110b4

// If you update these cases, update lexbase.lookaheadKeywords.

IIRC, this is needed to correctly handle objects that have the name "execute"

[spilchen]

Good idea, I posted it to #db-jobinfra-eng

Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @dt, @mw5h, and @rafiss)

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pkg/sql/parser/lexer.go line 330 at r1 (raw file):

Previously, rafiss (Rafi Shamim) wrote…

i think we need to add "execute" to the lookaheadKeywords slice:

cockroach/pkg/sql/parser/lexer.go

Line 228 in 9c110b4

// If you update these cases, update lexbase.lookaheadKeywords.

IIRC, this is needed to correctly handle objects that have the name "execute"

Hmm, it was added already. See update to pkg/sql/lexbase/predicates.go

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pkg/sql/parser/testdata/control_job line 642 at r1 (raw file):

Previously, rafiss (Rafi Shamim) wrote…

can we also verify that EXECUTE SCHEDULE SELECT 123 (the non-plural variant) parses?

Done.

[rafiss]

Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @dt and @mw5h)

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pkg/sql/parser/lexer.go line 330 at r1 (raw file):

Previously, spilchen wrote…

Hmm, it was added already. See update to pkg/sql/lexbase/predicates.go

Oops, I must have confused myself looking at my local diff