MDEV-5867 ALTER TABLE t1 ENGINE=InnoDB keeps bad options when t1 ENGINE is CONNECT

Comment out unknown options in SHOW CREATE TABLE unless IGNORE_BAD_TABLE_OPTIONS is used

1 files changed, 17 insertions, 0 deletions

diff --git a/sql/create_options.cc b/sql/create_options.cc
index d60639a4f4a..09153f7e35c 100644
--- a/sql/create_options.cc
+++ b/sql/create_options.cc
@@ -775,3 +775,20 @@ engine_option_value *merge_engine_table_options(engine_option_value *first,
                                    &first, &end);
   DBUG_RETURN(first);
 }
+
+bool is_engine_option_known(engine_option_value *opt,
+                            ha_create_table_option *rules)
+{
+  if (!rules)
+    return false;
+
+  for (; rules->name; rules++)
+  {
+      if (!my_strnncoll(system_charset_info,
+                        (uchar*)rules->name, rules->name_length,
+                        (uchar*)opt->name.str, opt->name.length))
+        return true;
+  }
+  return false;
+}
+