mysql-5.5.40

1 files changed, 17 insertions, 0 deletions

diff --git a/scripts/mysql_system_tables_fix.sql b/scripts/mysql_system_tables_fix.sql
index bcd3ef2005f..9bc61f38cea 100644
--- a/scripts/mysql_system_tables_fix.sql
+++ b/scripts/mysql_system_tables_fix.sql
@@ -668,6 +668,23 @@ INSERT INTO tmp_proxies_priv VALUES ('localhost', 'root', '', '', TRUE, '', now(
 INSERT INTO proxies_priv SELECT * FROM tmp_proxies_priv WHERE @had_proxies_priv_table=0;
 DROP TABLE tmp_proxies_priv;
 
+-- Checking for any duplicate hostname and username combination are exists.
+-- If exits we will throw error.
+DROP PROCEDURE IF EXISTS mysql.count_duplicate_host_names;
+DELIMITER //
+CREATE PROCEDURE mysql.count_duplicate_host_names()
+BEGIN
+  SET @duplicate_hosts=(SELECT count(*) FROM mysql.user GROUP BY user, lower(host) HAVING count(*) > 1 LIMIT 1);
+  IF @duplicate_hosts > 1 THEN
+    SIGNAL SQLSTATE '45000'  SET MESSAGE_TEXT = 'Multiple accounts exist for @user_name, @host_name that differ only in Host lettercase; remove all except one of them';
+  END IF;
+END //
+DELIMITER ;
+CALL mysql.count_duplicate_host_names();
+-- Get warnings (if any)
+SHOW WARNINGS;
+DROP PROCEDURE mysql.count_duplicate_host_names;
+
 # Convering the host name to lower case for existing users
 UPDATE user SET host=LOWER( host ) WHERE LOWER( host ) <> host;