Merge 10.4 into 10.5

1 files changed, 12 insertions, 0 deletions

diff --git a/sql/sql_alter.cc b/sql/sql_alter.cc
index 2a87d8069bc..75d792523c7 100644
--- a/sql/sql_alter.cc
+++ b/sql/sql_alter.cc
@@ -373,6 +373,18 @@ bool Sql_cmd_alter_table::execute(THD *thd)
   SELECT_LEX *select_lex= lex->first_select_lex();
   /* first table of first SELECT_LEX */
   TABLE_LIST *first_table= (TABLE_LIST*) select_lex->table_list.first;
+
+  const bool used_engine= lex->create_info.used_fields & HA_CREATE_USED_ENGINE;
+  DBUG_ASSERT((m_storage_engine_name.str != NULL) == used_engine);
+  if (used_engine)
+  {
+    if (resolve_storage_engine_with_error(thd, &lex->create_info.db_type,
+                                          lex->create_info.tmp_table()))
+      return true; // Engine not found, substitution is not allowed
+    if (!lex->create_info.db_type) // Not found, but substitution is allowed
+      lex->create_info.used_fields&= ~HA_CREATE_USED_ENGINE;
+  }
+
   /*
     Code in mysql_alter_table() may modify its HA_CREATE_INFO argument,
     so we have to use a copy of this structure to make execution