MXS-3064: Use latin1 charset

This prevents the server from selecting the charset under which the
queries are processed which can result in conflicts if the tables used are
not compatible with the charset of the string literals used in the query.

server/core/mysql_utils.cc

@@ -102,6 +102,12 @@ MYSQL* mxs_mysql_real_connect(MYSQL* con, SERVER* server, const char* user, cons
         }
     }
 
+    if (mysql && mysql_query(mysql, "SET NAMES latin1") != 0)
+    {
+        MXS_ERROR("Failed to set latin1 character set: %s", mysql_error(mysql));
+        mysql = NULL;
+    }
+
     if (mysql)
     {
         /** Copy the server charset */