sql: fix reset_sql_stats to truncate activity tables

Previously:
The reset stats on the ui and crdb_internal.reset_sql_stats() would
only reset the statement_statistics and transaction_statics tables.
This would leave the sql_activity table with old data. The reset stats
now truncates the sql_activity table as well.

Fixes: #104321
Epic: none

Release note (sql change): Fix crdb_internal.reset_sql_stats() to
 cleanup the sql_activity table which work as a cache for the stats.

pkg/sql/sql_activity_update_job_test.go

@@ -186,6 +186,34 @@ func TestSqlActivityUpdateJob(t *testing.T) {
 	err = row.Scan(&count)
 	require.NoError(t, err)
 	require.Equal(t, count, 1, "statement_activity after transfer: expect:1, actual:%d", count)
+
+	// Reset the stats and verify it's empty
+	_, err = db.ExecContext(ctx, "SELECT crdb_internal.reset_sql_stats()")
+	require.NoError(t, err)
+
+	row = db.QueryRowContext(ctx, "SELECT count_rows() "+
+		"FROM system.public.transaction_activity")
+	err = row.Scan(&count)
+	require.NoError(t, err)
+	require.Zero(t, count, "transaction_activity after transfer: expect:0, actual:%d", count)
+
+	row = db.QueryRowContext(ctx, "SELECT count_rows() "+
+		"FROM system.public.statement_activity")
+	err = row.Scan(&count)
+	require.NoError(t, err)
+	require.Zero(t, count, "statement_activity after transfer: expect:0, actual:%d", count)
+
+	row = db.QueryRowContext(ctx, "SELECT count_rows() "+
+		"FROM crdb_internal.transaction_activity")
+	err = row.Scan(&count)
+	require.NoError(t, err)
+	require.Zero(t, count, "transaction_activity after transfer: expect:0, actual:%d", count)
+
+	row = db.QueryRowContext(ctx, "SELECT count_rows() "+
+		"FROM crdb_internal.statement_activity")
+	err = row.Scan(&count)
+	require.NoError(t, err)
+	require.Zero(t, count, "statement_activity after transfer: expect:0, actual:%d", count)
 }
 
 // TestSqlActivityUpdateJob verifies that the

pkg/sql/sqlstats/persistedsqlstats/BUILD.bazel

@@ -24,6 +24,7 @@ go_library(
     visibility = ["//visibility:public"],
     deps = [
         "//pkg/base",
+        "//pkg/clusterversion",
         "//pkg/jobs",
         "//pkg/jobs/jobspb",
         "//pkg/scheduledjobs",

pkg/sql/sqlstats/persistedsqlstats/controller.go

@@ -13,6 +13,7 @@ package persistedsqlstats
 import (
 	"context"
 
+	"github.com/cockroachdb/cockroach/pkg/clusterversion"
 	"github.com/cockroachdb/cockroach/pkg/server/serverpb"
 	"github.com/cockroachdb/cockroach/pkg/settings/cluster"
 	"github.com/cockroachdb/cockroach/pkg/sql/isql"
@@ -68,9 +69,22 @@ func (s *Controller) ResetClusterSQLStats(ctx context.Context) error {
 			"TRUNCATE "+tableName)
 		return err
 	}
+
 	if err := resetSysTableStats("system.statement_statistics"); err != nil {
 		return err
 	}
 
-	return resetSysTableStats("system.transaction_statistics")
+	if err := resetSysTableStats("system.transaction_statistics"); err != nil {
+		return err
+	}
+
+	if !s.st.Version.IsActive(ctx, clusterversion.V23_1CreateSystemActivityUpdateJob) {
+		return nil
+	}
+
+	if err := resetSysTableStats("system.statement_activity"); err != nil {
+		return err
+	}
+
+	return resetSysTableStats("system.transaction_activity")
 }