Fix for 5.1 for BUG#10491: Server returns data as charset binary

SHOW CREATE TABLE or SELECT FROM I_S.

This is the last patch for this bug, which depends on the big
CS patch and was pending.

The problem was that SHOW CREATE statements returned original
queries in the binary character set. That could cause the query
to be unreadable.

The fix is to use original character_set_client when sending
the original query to the client. In order to preserve the query
in mysqldump, 'binary' character set results should be set when
issuing SHOW CREATE statement. If either source or destination
character set is 'binary' , no conversion is performed.
The idea is that since the source character set is no longer
'binary', we fix the destination character set to still produce
valid dumps.


client/mysqldump.c:
  Switch character_set_results of mysqldump-connection before
  calling SHOW CREATE statements for the objects.
mysql-test/r/show_check.result:
  Result file.
mysql-test/t/show_check.test:
  Add test case for the part of BUG#10491.
sql/events.cc:
  Send original query in the original character set.
sql/sp_head.cc:
  Send original query in the original character set.
sql/sql_show.cc:
  Send original query in the original character set.

1 files changed, 64 insertions, 0 deletions

diff --git a/mysql-test/t/show_check.test b/mysql-test/t/show_check.test
index 341c9039390..2f474d0335b 100644
--- a/mysql-test/t/show_check.test
+++ b/mysql-test/t/show_check.test
@@ -897,4 +897,68 @@ DROP TABLE t1;
 DROP PROCEDURE p1;
 DEALLOCATE PREPARE stmt1;
 
+#
+# BUG#10491: Server returns data as charset binary SHOW CREATE TABLE or SELECT
+# FROM INFORMATION_SCHEMA.
+#
+# Before the change performed to fix the bug, the metadata of the output of
+# SHOW CREATE statements would always describe the result as 'binary'. That
+# would ensure that the result is never converted to character_set_client
+# (which was essential to mysqldump). Now we return to the client the actual
+# character set of the object -- which is character_set_client of the
+# connection that issues the CREATE statement, and this triggers an automatic
+# conversion to character_set_results of the connection that issues SHOW CREATE
+# statement.
+#
+# This test demonstrates that this conversion indeed is taking place.
+#
+
+# Prepare: create objects in a one character set.
+
+set names koi8r;
+
+--disable_warnings
+DROP VIEW IF EXISTS v1;
+DROP PROCEDURE IF EXISTS p1;
+DROP FUNCTION IF EXISTS f1;
+DROP TABLE IF EXISTS t1;
+DROP EVENT IF EXISTS ev1;
+--enable_warnings
+
+CREATE VIEW v1 AS SELECT 'ΤΕΣΤ' AS test;
+
+CREATE PROCEDURE p1() SELECT 'ΤΕΣΤ' AS test;
+
+CREATE FUNCTION f1() RETURNS CHAR(10) RETURN 'ΤΕΣΤ';
+
+CREATE TABLE t1(c1 CHAR(10));
+CREATE TRIGGER t1_bi BEFORE INSERT ON t1
+  FOR EACH ROW
+    SET NEW.c1 = 'ΤΕΣΤ';
+
+CREATE EVENT ev1 ON SCHEDULE AT '2030-01-01 00:00:00' DO SELECT 'ΤΕΣΤ' AS test;
+
+# Test: switch the character set and show that SHOW CREATE output is
+# automatically converted to the new character_set_client.
+
+set names utf8;
+
+SHOW CREATE VIEW v1;
+
+SHOW CREATE PROCEDURE p1;
+
+SHOW CREATE FUNCTION f1;
+
+SHOW CREATE TRIGGER t1_bi;
+
+SHOW CREATE EVENT ev1;
+
+# Cleanup.
+
+DROP VIEW v1;
+DROP PROCEDURE p1;
+DROP FUNCTION f1;
+DROP TABLE t1;
+DROP EVENT ev1;
+
 --echo End of 5.1 tests