setGaleraOpts(): execute SET SESSION wsrep_sync_wait directly

to save extra roundtrips for preparing and closing a statement.

This change was first contributed as
<Icinga/icingadb#751>. However, after the
library split, the code went from icingadb to the icinga-go-library.

Co-Authored-By: Alvar Penning <[email protected]>

Author: Al2Klimov

database/utils.go

@@ -8,6 +8,7 @@ import (
 	"github.com/icinga/icinga-go-library/strcase"
 	"github.com/icinga/icinga-go-library/types"
 	"github.com/pkg/errors"
+	"strconv"
 )
 
 // CantPerformQuery wraps the given error with the specified query that cannot be executed.
@@ -50,29 +51,17 @@ func SplitOnDupId[T IDer]() com.BulkChunkSplitPolicy[T] {
 //
 // https://mariadb.com/kb/en/galera-cluster-system-variables/#wsrep_sync_wait
 func setGaleraOpts(ctx context.Context, conn driver.Conn, wsrepSyncWait int64) error {
-	const galeraOpts = "SET SESSION wsrep_sync_wait=?"
+	galeraOpts := "SET SESSION wsrep_sync_wait=" + strconv.FormatInt(wsrepSyncWait, 10)
 
-	stmt, err := conn.(driver.ConnPrepareContext).PrepareContext(ctx, galeraOpts)
+	_, err := conn.(driver.ExecerContext).ExecContext(ctx, galeraOpts, nil)
 	if err != nil {
 		if errors.Is(err, &mysql.MySQLError{Number: 1193}) { // Unknown system variable
 			return nil
 		}
 
-		return errors.Wrap(err, "cannot prepare "+galeraOpts)
-	}
-	// This is just for an unexpected exit and any returned error can safely be ignored and in case
-	// of the normal function exit, the stmt is closed manually, and its error is handled gracefully.
-	defer func() { _ = stmt.Close() }()
-
-	_, err = stmt.(driver.StmtExecContext).ExecContext(ctx, []driver.NamedValue{{Value: wsrepSyncWait}})
-	if err != nil {
 		return errors.Wrap(err, "cannot execute "+galeraOpts)
 	}
 
-	if err = stmt.Close(); err != nil {
-		return errors.Wrap(err, "cannot close prepared statement "+galeraOpts)
-	}
-
 	return nil
 }