workload/schemachange: add INSPECT operation to random schema workload

[spilchen]

Adds a new inspect operation to the schema change workload, enabling random generation of INSPECT TABLE and INSPECT DATABASE statements.

Features:

• Support for TABLE/DB targets, AS OF SYSTEM TIME
• Always runs in DETACHED mode so that it can be run inside a transaciton
• Results checked post-run via SHOW INSPECT ERRORS

Errors reported in JSON, consistent with existing workload logs

Closes #155483
Epic: CRDB-55075
Release note: none

[cockroach-teamcity]

This change is 

[fqazi]

A few minor comments, nice work!

@fqazi reviewed 4 of 4 files at r1, all commit messages.
Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @shailendra-patel and @williamchoe3)

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pkg/workload/schemachange/schemachange.go line 210 at r1 (raw file):

	var totalErrors int
	for _, jobID := range jobIDs {
		query := fmt.Sprintf("SHOW INSPECT ERRORS FOR JOB %d WITH DETAILS", jobID)

Nit: Do we want to explicit select columns via SELECT <COLUMNS> FROM [SHOW ...] for future proofing (if the columns ever change?)

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pkg/workload/schemachange/schemachange.go line 350 at r1 (raw file):

			shutdownErr := tracerProvider.Shutdown(ctx)
			s.schemaWorkloadResultAnnotator.logWorkloadStats(stdoutLog)
			return errors.CombineErrors(inspectErr, errors.CombineErrors(closeErr, shutdownErr))

Lets use errors.Join instead.

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pkg/workload/schemachange/operation_generator.go line 3460 at r1 (raw file):

func (og *operationGenerator) inspect(ctx context.Context, tx pgx.Tx) (*opStmt, error) {
	stmt := makeOpStmt(OpStmtDML)

This workload runs on mixed version, is it safe to create the job in a mixed version setting? Think we may want a version gate.

[spilchen]

Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @fqazi, @shailendra-patel, and @williamchoe3)

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pkg/workload/schemachange/operation_generator.go line 3460 at r1 (raw file):

Previously, fqazi (Faizan Qazi) wrote…

This workload runs on mixed version, is it safe to create the job in a mixed version setting? Think we may want a version gate.

Good call. I updated optype.go for this.

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pkg/workload/schemachange/schemachange.go line 350 at r1 (raw file):

Previously, fqazi (Faizan Qazi) wrote…

Lets use errors.Join instead.

Done.

[fqazi]

@fqazi reviewed 2 of 2 files at r2, all commit messages.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @shailendra-patel and @williamchoe3)

[github-actions]

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