1 files changed, 17 insertions, 0 deletions
diff --git a/sql/sql_insert.cc b/sql/sql_insert.cc
index 9a351085b3a..b108ff75f44 100644
--- a/sql/sql_insert.cc
+++ b/sql/sql_insert.cc
@@ -1333,6 +1333,23 @@ bool mysql_prepare_insert(THD *thd, TABLE_LIST *table_list,
 
 static int last_uniq_key(TABLE *table,uint keynr)
 {
+  /*
+    When an underlying storage engine informs that the unique key
+    conflicts are not reported in the ascending order by setting
+    the HA_DUPLICATE_KEY_NOT_IN_ORDER flag, we cannot rely on this
+    information to determine the last key conflict.
+   
+    The information about the last key conflict will be used to
+    do a replace of the new row on the conflicting row, rather
+    than doing a delete (of old row) + insert (of new row).
+   
+    Hence check for this flag and disable replacing the last row
+    by returning 0 always. Returning 0 will result in doing
+    a delete + insert always.
+  */
+  if (table->file->ha_table_flags() & HA_DUPLICATE_KEY_NOT_IN_ORDER)
+    return 0;
+
   while (++keynr < table->s->keys)
     if (table->key_info[keynr].flags & HA_NOSAME)
       return 0;