Improve code remove transaction managment from it

Author: hladush

internal/pkg/janitor/job.go

@@ -28,6 +28,9 @@ var queryOldJobsTagsDelete string
 //go:embed queries/old_jobs_delete.sql
 var queryOldJobsDelete string
 
+//go:embed queries/old_job_biggest_id.sql
+var queryOldJobsBiggestID string
+
 var (
 	queriesForOldJobsCleanup = []string{
 		queryOldJobsClusterTagsDelete,
@@ -101,33 +104,31 @@ func (j *Janitor) cleanupFinishedJobs() error {
 	if j.FinishedJobRetentionDays == 0 {
 		return nil
 	}
-	// Start transactional session
-	sess, err := j.db.NewSession(true)
+	// open session
+	sess, err := j.db.NewSession(false)
 	if err != nil {
 		return err
 	}
 	defer sess.Close()
 
-	defer func() {
-		_ = sess.Rollback()
-	}()
 
-	exec := func(query string, args ...any) error {
-		if _, err := sess.Exec(query, args...); err != nil {
-			return fmt.Errorf("failed to exec query %q: %w", query, err)
-		}
-		return nil
+	// get biggest ID of old jobs
+	row, err := sess.QueryRow(queryOldJobsBiggestID, j.FinishedJobRetentionDays)
+	if err != nil {
+		return fmt.Errorf("failed to get biggest ID of old jobs: %w", err)
+	}
+	
+	var biggestID int
+	if err := row.Scan(&biggestID); err != nil {
+		return fmt.Errorf("failed to get biggest ID of old jobs: %w", err)
 	}
 
+	// remove old jobs data
 	for _, q := range queriesForOldJobsCleanup {
-		if err := exec(q, j.FinishedJobRetentionDays); err != nil {
+		if _, err := sess.Exec(q, biggestID); err != nil {
 			return err
 		}
 	}
 
-	if err := sess.Commit(); err != nil {
-		return fmt.Errorf("failed to commit cleanup transaction: %w", err)
-	}
-	
 	return nil
 }

internal/pkg/janitor/queries/old_job_biggest_id.sql

@@ -0,0 +1 @@
+SELECT MAX(system_job_id) FROM jobs WHERE updated_at < extract(epoch FROM now() - ($1 || ' days')::interval)::int;

internal/pkg/janitor/queries/old_jobs_cluster_tags_delete.sql

@@ -1,4 +1,7 @@
 DELETE FROM job_cluster_tags
 WHERE system_job_id IN (
-  SELECT system_job_id FROM jobs WHERE updated_at < extract(epoch FROM now() - ($1 || ' days')::interval)::int
+  SELECT system_job_id
+  FROM job_cluster_tags
+  WHERE system_job_id <= $1
+  LIMIT 1000
 );

internal/pkg/janitor/queries/old_jobs_command_tags_delete.sql

@@ -1,5 +1,8 @@
 
 DELETE FROM job_command_tags
 WHERE system_job_id IN (
-  SELECT system_job_id FROM jobs WHERE updated_at < extract(epoch FROM now() - ($1 || ' days')::interval)::int
-);
+  SELECT system_job_id
+  FROM job_command_tags
+  WHERE system_job_id <= $1
+  LIMIT 1000
+);

internal/pkg/janitor/queries/old_jobs_delete.sql

@@ -1,3 +1,8 @@
 
 DELETE FROM jobs
-WHERE updated_at < extract(epoch FROM now() - ($1 || ' days')::interval)::int;
+WHERE system_job_id IN (
+  SELECT system_job_id
+  FROM jobs
+  WHERE system_job_id <= $1
+  LIMIT 1000
+);

internal/pkg/janitor/queries/old_jobs_tags_delete.sql

@@ -1,4 +1,7 @@
 DELETE FROM job_tags
 WHERE system_job_id IN (
-  SELECT system_job_id FROM jobs WHERE updated_at < extract(epoch FROM now() - ($1 || ' days')::interval)::int
-);
+  SELECT system_job_id
+  FROM job_tags
+  WHERE system_job_id <= $1
+  LIMIT 1000
+);