diff --git a/mysql-test/r/variables.result b/mysql-test/r/variables.result index efcc3d21144dcee957442043d41ebe4c647298f2..67c78d82a24332bd8639473695f72355dfa72ae6 100644 --- a/mysql-test/r/variables.result +++ b/mysql-test/r/variables.result @@ -491,6 +491,11 @@ SHOW VARIABLES LIKE 'table_cache'; Variable_name Value table_cache 1 SET GLOBAL table_cache=DEFAULT; +set character_set_results=NULL; +select ifnull(@@character_set_results,"really null"); +ifnull(@@character_set_results,"really null") +really null +set names latin1; select @@have_innodb; @@have_innodb # diff --git a/mysql-test/t/variables.test b/mysql-test/t/variables.test index f888541f17ae418b6b9faccc1db8108c44eb34c2..a8844070207eff8cc0046329e2d141ac083db945 100644 --- a/mysql-test/t/variables.test +++ b/mysql-test/t/variables.test @@ -380,6 +380,14 @@ SET GLOBAL table_cache=-1; SHOW VARIABLES LIKE 'table_cache'; SET GLOBAL table_cache=DEFAULT; +# +# Bugs12363: character_set_results is nullable, +# but value_ptr returns string "NULL" +# +set character_set_results=NULL; +select ifnull(@@character_set_results,"really null"); +set names latin1; + # End of 4.1 tests # diff --git a/sql/set_var.cc b/sql/set_var.cc index c0186880a59cbab9b95082f27ee3bc648db54ad2..94968f664fdcd6950f0dc0caa9755f1396cf77ac 100644 --- a/sql/set_var.cc +++ b/sql/set_var.cc @@ -1602,11 +1602,17 @@ Item *sys_var::item(THD *thd, enum_var_type var_type, LEX_STRING *base) return new Item_int((int32) *(my_bool*) value_ptr(thd, var_type, base),1); case SHOW_CHAR: { - Item_string *tmp; + Item *tmp; pthread_mutex_lock(&LOCK_global_system_variables); char *str= (char*) value_ptr(thd, var_type, base); - tmp= new Item_string(str, strlen(str), - system_charset_info, DERIVATION_SYSCONST); + if (str) + tmp= new Item_string(str, strlen(str), + system_charset_info, DERIVATION_SYSCONST); + else + { + tmp= new Item_null(); + tmp->collation.set(system_charset_info, DERIVATION_SYSCONST); + } pthread_mutex_unlock(&LOCK_global_system_variables); return tmp; } @@ -1896,7 +1902,7 @@ byte *sys_var_character_set::value_ptr(THD *thd, enum_var_type type, LEX_STRING *base) { CHARSET_INFO *cs= ci_ptr(thd,type)[0]; - return cs ? (byte*) cs->csname : (byte*) "NULL"; + return cs ? (byte*) cs->csname : (byte*) NULL; }