Bug#8412: For replication to work correctly, the prologue and

epilogue to an SQL statement should not have an error code even
when the SQL statement itself has an error code.

mysql-test/r/rpl_insert_id.result

@@ -69,3 +69,8 @@ b	c
 9	13
 drop table t1;
 drop table t2;
+SET TIMESTAMP=1000000000;
+CREATE TABLE t1 ( a INT UNIQUE );
+SET FOREIGN_KEY_CHECKS=0;
+INSERT INTO t1 VALUES (1),(1);
+Duplicate entry '1' for key 1

mysql-test/t/rpl_insert_id.test

@@ -62,3 +62,19 @@ drop table t2;
 save_master_pos;
 connection slave;
 sync_with_master;
+
+#
+# Bug#8412: Error codes reported in binary log for CHARACTER SET,
+#           FOREIGN_KEY_CHECKS
+#
+connection master;
+SET TIMESTAMP=1000000000;
+CREATE TABLE t1 ( a INT UNIQUE );
+SET FOREIGN_KEY_CHECKS=0;
+--error 1062
+INSERT INTO t1 VALUES (1),(1);
+sync_slave_with_master;
+
+
+
+

sql/log.cc

@@ -1182,6 +1182,7 @@ bool MYSQL_LOG::write(Log_event* event_info)
 	p= strmov(strmov(buf, "SET CHARACTER SET "),
 		  thd->variables.convert_set->name);
 	Query_log_event e(thd, buf, (ulong) (p - buf), 0);
+	e.error_code = 0;	// This statement cannot fail (see [1]).
 	e.set_log_pos(this);
 	if (e.write(file))
 	  goto err;
@@ -1199,12 +1200,22 @@ bool MYSQL_LOG::write(Log_event* event_info)
       {
 	Query_log_event e(thd, "SET FOREIGN_KEY_CHECKS=0", 24, 0);
 	e.set_log_pos(this);
+	e.error_code = 0;	// This statement cannot fail (see [1]).
 	if (e.write(file))
 	  goto err;
       }
     }
 
-    /* Write the SQL command */
+    /* 
+       Write the SQL command 
+       
+       [1] If this statement has an error code, the slave is required to fail
+           with the same error code or stop. The preamble and epilogue should
+           *not* have this error code since the execution of those is
+           guaranteed *not* to produce any error code. This would therefore
+           stop the slave even if the execution of the real statement can be
+           handled gracefully by the slave.
+     */
 
     event_info->set_log_pos(this);
     if (event_info->write(file))
@@ -1218,6 +1229,7 @@ bool MYSQL_LOG::write(Log_event* event_info)
       {
         Query_log_event e(thd, "SET FOREIGN_KEY_CHECKS=1", 24, 0);
         e.set_log_pos(this);
+	e.error_code = 0;	// This statement cannot fail (see [1]).
         if (e.write(file))
           goto err;
       }
@@ -1226,6 +1238,7 @@ bool MYSQL_LOG::write(Log_event* event_info)
       {
 	Query_log_event e(thd, "SET CHARACTER SET DEFAULT", 25, 0);
 	e.set_log_pos(this);
+	e.error_code = 0;	// This statement cannot fail (see [1]).
 	if (e.write(file))
 	  goto err;
       }