From 6dfb184f092617919f4399abbc25fbdc01d4ed2b Mon Sep 17 00:00:00 2001
From: "svoj@mysql.com/june.mysql.com" <>
Date: Tue, 18 Mar 2008 20:25:34 +0400
Subject: BUG#34768 - nondeterministic INSERT using LIMIT logged in stmt mode
 if             binlog_format=mixed

Statement-based replication of DELETE ... LIMIT, UPDATE ... LIMIT,
INSERT ... SELECT ... LIMIT is not safe as order of rows is not
defined.

With this fix, we issue a warning that this statement is not safe to
replicate in statement mode, or go to row-based mode in mixed mode.

Note that we may consider a statement as safe if ORDER BY primary_key
is present. However it may confuse users to see very similiar statements
replicated differently.

Note 2: regular UPDATE statement (w/o LIMIT) is unsafe as well, but
this patch doesn't address this issue. See comment from Kristian
posted 18 Mar 10:55.
---
 sql/sql_delete.cc | 13 +++++++++++++
 1 file changed, 13 insertions(+)

(limited to 'sql/sql_delete.cc')

diff --git a/sql/sql_delete.cc b/sql/sql_delete.cc
index 990f7713561..abf25e96be0 100644
--- a/sql/sql_delete.cc
+++ b/sql/sql_delete.cc
@@ -418,6 +418,19 @@ bool mysql_prepare_delete(THD *thd, TABLE_LIST *table_list, Item **conds)
   DBUG_ENTER("mysql_prepare_delete");
   List<Item> all_fields;
 
+  /*
+    Statement-based replication of DELETE ... LIMIT is not safe as order of
+    rows is not defined, so in mixed mode we go to row-based.
+
+    Note that we may consider a statement as safe if ORDER BY primary_key
+    is present. However it may confuse users to see very similiar statements
+    replicated differently.
+  */
+  if (thd->lex->current_select->select_limit)
+  {
+    thd->lex->set_stmt_unsafe();
+    thd->set_current_stmt_binlog_row_based_if_mixed();
+  }
   thd->lex->allow_sum_func= 0;
   if (setup_tables_and_check_access(thd, &thd->lex->select_lex.context,
                                     &thd->lex->select_lex.top_join_list,
-- 
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