From 1dff783854d165611beb35a14f7ee7c853903bd6 Mon Sep 17 00:00:00 2001
From: "bell@52.0.168.192.in-addr.arpa" <>
Date: Wed, 10 Aug 2005 18:58:55 +0300
Subject: [PATCH] block using QC in case of having tables locked by LOCK...
 (BUG#12385)

---
 mysql-test/r/query_cache_noembeded.result | 18 +++++++++++++
 mysql-test/t/query_cache_noembeded.test   | 33 +++++++++++++++++++++++
 sql/sql_cache.cc                          |  7 +++--
 3 files changed, 56 insertions(+), 2 deletions(-)
 create mode 100644 mysql-test/r/query_cache_noembeded.result
 create mode 100644 mysql-test/t/query_cache_noembeded.test

diff --git a/mysql-test/r/query_cache_noembeded.result b/mysql-test/r/query_cache_noembeded.result
new file mode 100644
index 00000000000..f2b06eea45d
--- /dev/null
+++ b/mysql-test/r/query_cache_noembeded.result
@@ -0,0 +1,18 @@
+set GLOBAL query_cache_size=1355776;
+reset query cache;
+flush status;
+CREATE TABLE t1 ( a INT NOT NULL PRIMARY KEY AUTO_INCREMENT ) ENGINE =
+MyISAM;
+LOCK TABLE t1 READ LOCAL;
+INSERT INTO t1 VALUES (), (), ();
+SELECT * FROM t1;
+a
+SELECT * FROM t1;
+a
+1
+2
+3
+SELECT * FROM t1;
+a
+drop table t1;
+set GLOBAL query_cache_size=default;
diff --git a/mysql-test/t/query_cache_noembeded.test b/mysql-test/t/query_cache_noembeded.test
new file mode 100644
index 00000000000..c909bfcdf3b
--- /dev/null
+++ b/mysql-test/t/query_cache_noembeded.test
@@ -0,0 +1,33 @@
+-- source include/have_query_cache.inc
+-- source include/not_embedded.inc
+
+#
+# Tests with query cache
+#
+set GLOBAL query_cache_size=1355776;
+
+# Reset query cache variables.
+
+reset query cache;
+flush status;
+
+#
+# do not use QC if tables locked (BUG#12385)
+#
+connect (root,localhost,root,,test,$MASTER_MYPORT,master.sock);
+connection root;
+CREATE TABLE t1 ( a INT NOT NULL PRIMARY KEY AUTO_INCREMENT ) ENGINE =
+MyISAM;
+LOCK TABLE t1 READ LOCAL;
+connect (root2,localhost,root,,test,$MASTER_MYPORT,master.sock);
+connection root2;
+INSERT INTO t1 VALUES (), (), ();
+connection root;
+SELECT * FROM t1;
+connection root2;
+SELECT * FROM t1;
+connection root;
+SELECT * FROM t1;
+drop table t1;
+
+set GLOBAL query_cache_size=default;
diff --git a/sql/sql_cache.cc b/sql/sql_cache.cc
index d729a6cc301..667b6e546d3 100644
--- a/sql/sql_cache.cc
+++ b/sql/sql_cache.cc
@@ -739,7 +739,7 @@ void Query_cache::store_query(THD *thd, TABLE_LIST *tables_used)
   TABLE_COUNTER_TYPE local_tables;
   ulong tot_length;
   DBUG_ENTER("Query_cache::store_query");
-  if (query_cache_size == 0)
+  if (query_cache_size == 0 || thd->locked_tables)
     DBUG_VOID_RETURN;
 
   if ((local_tables= is_cacheable(thd, thd->query_length,
@@ -750,7 +750,10 @@ void Query_cache::store_query(THD *thd, TABLE_LIST *tables_used)
     STRUCT_LOCK(&structure_guard_mutex);
 
     if (query_cache_size == 0)
+    {
+      STRUCT_UNLOCK(&structure_guard_mutex);
       DBUG_VOID_RETURN;
+    }
     DUMP(this);
 
     /* Key is query + database + flag */
@@ -874,7 +877,7 @@ Query_cache::send_result_to_client(THD *thd, char *sql, uint query_length)
   byte flags;
   DBUG_ENTER("Query_cache::send_result_to_client");
 
-  if (query_cache_size == 0 ||
+  if (query_cache_size == 0 || thd->locked_tables ||
       /*
 	it is not possible to check has_transactions() function of handler
 	because tables not opened yet