meta: Add a GetDBMeta function to meta. (#53684)

close #53685

pkg/meta/meta.go

@@ -989,17 +989,27 @@ func (m *Meta) IterTables(dbID int64, fn func(info *model.TableInfo) error) erro
  return errors.Trace(err)
 }
 
-// ListTables shows all tables in database.
-func (m *Meta) ListTables(dbID int64) ([]*model.TableInfo, error) {
+// GetMetasByDBID return all meta information of a database.
+// Note(dongmen): This method is used by TiCDC to reduce the time of changefeed initialization.
+// Ref: https://github.com/pingcap/tiflow/issues/11109
+func (m *Meta) GetMetasByDBID(dbID int64) ([]structure.HashPair, error) {
  dbKey := m.dbKey(dbID)
  if err := m.checkDBExists(dbKey); err != nil {
  return nil, errors.Trace(err)
  }
-
  res, err := m.txn.HGetAll(dbKey)
  if err != nil {
  return nil, errors.Trace(err)
  }
+ return res, nil
+}
+
+// ListTables shows all tables in database.
+func (m *Meta) ListTables(dbID int64) ([]*model.TableInfo, error) {
+ res, err := m.GetMetasByDBID(dbID)
+ if err != nil {
+ return nil, errors.Trace(err)
+ }
 
  tables := make([]*model.TableInfo, 0, len(res)/2)
  for _, r := range res {
@@ -1024,12 +1034,7 @@ func (m *Meta) ListTables(dbID int64) ([]*model.TableInfo, error) {
 
 // ListSimpleTables shows all simple tables in database.
 func (m *Meta) ListSimpleTables(dbID int64) ([]*model.TableNameInfo, error) {
- dbKey := m.dbKey(dbID)
- if err := m.checkDBExists(dbKey); err != nil {
- return nil, errors.Trace(err)
- }
-
- res, err := m.txn.HGetAll(dbKey)
+ res, err := m.GetMetasByDBID(dbID)
  if err != nil {
  return nil, errors.Trace(err)
  }