3 messages in com.mysql.lists.bugsRe: Bug in Union?!| From | Sent On | Attachments |
|---|---|---|
| Georg Richter | 22 Dec 2002 07:07 | |
| Sinisa Milivojevic | 23 Dec 2002 12:16 | |
| Sinisa Milivojevic | 24 Dec 2002 10:41 |
| Subject: | Re: Bug in Union?! |
|---|---|
| From: | Sinisa Milivojevic (sin...@mysql.com) |
| Date: | 12/23/2002 12:16:13 PM |
| List: | com.mysql.lists.bugs |
Georg Richter writes:
Hi,
I'm not sure if this an error... if not it should be documented
how-to-repeat:
mysql> create table foo (bar int); Query OK, 0 rows affected (0.00 sec)
mysql> insert into foo values (1),(2),(3),(4),(5); Query OK, 5 rows affected (0.00 sec) Records: 5 Duplicates: 0 Warnings: 0
mysql> (select * from foo limit 1,1) union select * from foo limit 3,1; Empty set (0.00 sec)
(select * from foo limit 1,1) union (select * from foo limit 3,1) works ok, also (select * from foo limit 1,1) union (select * from foo) limit 3,1.
Regards
Georg
Hi!
I do not think that mixing UNION with and without braces should be allowed. For many reasons, although standard is not clear on this one.
Therefore, I will propose the following patch:
===== sql/sql_yacc.yy 1.209 vs edited =====
*** /tmp/sql_yacc.yy-1.209-23919 Wed Dec 18 16:26:45 2002
--- edited/sql/sql_yacc.yy Mon Dec 23 21:59:45 2002
***************
*** 1668,1679 ****
'(' SELECT_SYM select_part2 ')'
{
LEX *lex= Lex;
! SELECT_LEX_NODE * sel= lex->current_select;
if (sel->set_braces(1))
{
send_error(lex->thd, ER_SYNTAX_ERROR);
YYABORT;
}
/* select in braces, can't contain global parameters */
sel->master_unit()->global_parameters=
sel->master_unit();
--- 1668,1684 ----
'(' SELECT_SYM select_part2 ')'
{
LEX *lex= Lex;
! SELECT_LEX * sel= lex->current_select->select_lex();
if (sel->set_braces(1))
{
send_error(lex->thd, ER_SYNTAX_ERROR);
YYABORT;
}
+ if (sel->linkage == UNION_TYPE &&
!sel->master_unit()->first_select()->braces)
+ {
+ send_error(lex->thd, ER_SYNTAX_ERROR);
+ YYABORT;
+ }
/* select in braces, can't contain global parameters */
sel->master_unit()->global_parameters=
sel->master_unit();
***************
*** 1683,1693 ****
--- 1688,1704 ----
select_part2
{
LEX *lex= Lex;
+ SELECT_LEX * sel= lex->current_select->select_lex();
if (lex->current_select->set_braces(0))
{
send_error(lex->thd, ER_SYNTAX_ERROR);
YYABORT;
}
+ if (sel->linkage == UNION_TYPE &&
sel->master_unit()->first_select()->braces)
+ {
+ send_error(lex->thd, ER_SYNTAX_ERROR);
+ YYABORT;
+ }
}
union_clause
;
***************
*** 1695,1700 ****
--- 1706,1712 ----
select_part2:
{
LEX *lex=Lex;
+ SELECT_LEX * sel= lex->current_select->select_lex();
if (lex->current_select == &lex->select_lex)
lex->lock_option= TL_READ; /* Only for global SELECT */
mysql_init_select(lex);
***************
*** 2509,2515 ****
lex->current_select= unit->outer_select();
if (!($$= lex->current_select->
add_table_to_list(lex->thd, new Table_ident(unit), $5, 0,
! lex->lock_option)))
YYABORT;
};
--- 2521,2529 ---- lex->current_select= unit->outer_select(); if (!($$= lex->current_select-> add_table_to_list(lex->thd, new Table_ident(unit), $5, 0, ! lex->lock_option,(List<String> *)0, ! (List<String> *)0))) ! YYABORT; };
May be I fix this in 4.0 too, only fix will be different.
-- __ ___ ___ ____ __ / |/ /_ __/ __/ __ \/ / Mr. Sinisa Milivojevic <sin...@mysql.com> / /|_/ / // /\ \/ /_/ / /__ MySQL AB, Fulltime Developer /_/ /_/\_, /___/\___\_\___/ Larnaca, Cyprus <___/ www.mysql.com
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