From 2a86768e9e1ca85ec4380e29df72fbdcea34a85d Mon Sep 17 00:00:00 2001
From: Sergey Glukhov <Sergey.Glukhov@sun.com>
Date: Fri, 25 Jun 2010 12:01:47 +0400
Subject: [PATCH] Bug#54422 query with = 'variables' During creation of the
 table list of processed tables hidden I_S table 'VARIABLES' is erroneously
 added into the table list. it leads to ER_UNKNOWN_TABLE error in
 TABLE_LIST::add_table_to_list() function. The fix is to skip addition of
 hidden I_S tables into the table list.

mysql-test/r/information_schema.result:
  test case
mysql-test/t/information_schema.test:
  test case
sql/sql_show.cc:
  The fix is to skip addition of hidden I_S
  tables into the table list.
---
 mysql-test/r/information_schema.result | 10 ++++++++++
 mysql-test/t/information_schema.test   |  9 +++++++++
 sql/sql_show.cc                        |  4 +++-
 3 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/mysql-test/r/information_schema.result b/mysql-test/r/information_schema.result
index 4ed7e4e700b..b7b65598c6d 100644
--- a/mysql-test/r/information_schema.result
+++ b/mysql-test/r/information_schema.result
@@ -1747,4 +1747,14 @@ COUNT(*)
 DROP USER nonpriv;
 DROP TABLE db1.t1;
 DROP DATABASE db1;
+
+Bug#54422 query with = 'variables'
+
+CREATE TABLE variables(f1 INT);
+SELECT COLUMN_DEFAULT, TABLE_NAME
+FROM INFORMATION_SCHEMA.COLUMNS
+WHERE INFORMATION_SCHEMA.COLUMNS.TABLE_NAME = 'variables';
+COLUMN_DEFAULT	TABLE_NAME
+NULL	variables
+DROP TABLE variables;
 End of 5.1 tests.
diff --git a/mysql-test/t/information_schema.test b/mysql-test/t/information_schema.test
index f3ce3d87252..fa4b880aead 100644
--- a/mysql-test/t/information_schema.test
+++ b/mysql-test/t/information_schema.test
@@ -1445,6 +1445,15 @@ DROP USER nonpriv;
 DROP TABLE db1.t1;
 DROP DATABASE db1;
 
+--echo
+--echo Bug#54422 query with = 'variables'
+--echo
+
+CREATE TABLE variables(f1 INT);
+SELECT COLUMN_DEFAULT, TABLE_NAME
+FROM INFORMATION_SCHEMA.COLUMNS
+WHERE INFORMATION_SCHEMA.COLUMNS.TABLE_NAME = 'variables';
+DROP TABLE variables;
 
 --echo End of 5.1 tests.
 
diff --git a/sql/sql_show.cc b/sql/sql_show.cc
index f634c149fd9..33abf356718 100644
--- a/sql/sql_show.cc
+++ b/sql/sql_show.cc
@@ -2921,7 +2921,9 @@ make_table_name_list(THD *thd, List<LEX_STRING> *table_names, LEX *lex,
   {
     if (with_i_schema)
     {
-      if (find_schema_table(thd, lookup_field_vals->table_value.str))
+      ST_SCHEMA_TABLE *schema_table=
+        find_schema_table(thd, lookup_field_vals->table_value.str);
+      if (schema_table && !schema_table->hidden)
       {
         if (table_names->push_back(&lookup_field_vals->table_value))
           return 1;