From fe5bcb475c56f804732781623d1c2c82a159e94d Mon Sep 17 00:00:00 2001 From: Alexander Nozdrin Date: Mon, 31 May 2010 17:38:02 +0400 Subject: [PATCH] Backport of - revid:sp1r-svoj@mysql.com/june.mysql.com-20080324111246-00461 - revid:sp1r-svoj@mysql.com/june.mysql.com-20080414125521-40866 BUG#35274 - merge table doesn't need any base tables, gives error 124 when key accessed SELECT queries that use index against a merge table with empty underlying tables list may return with error "Got error 124 from storage engine". The problem was that wrong error being returned. mysql-test/r/merge.result: Backport of - revid:sp1r-svoj@mysql.com/june.mysql.com-20080324111246-00461 - revid:sp1r-svoj@mysql.com/june.mysql.com-20080414125521-40866 A test case for BUG#35274. Modified a test case according to fix for BUG#35274. Key based reads are now allowed for merge tables with no underlying tables defined. mysql-test/t/merge.test: Backport of - revid:sp1r-svoj@mysql.com/june.mysql.com-20080324111246-00461 - revid:sp1r-svoj@mysql.com/june.mysql.com-20080414125521-40866 A test case for BUG#35274. Modified a test case according to fix for BUG#35274. Key based reads are now allowed for merge tables with no underlying tables defined. storage/myisammrg/myrg_queue.c: Backport of - revid:sp1r-svoj@mysql.com/june.mysql.com-20080324111246-00461 - revid:sp1r-svoj@mysql.com/june.mysql.com-20080414125521-40866 Return "end of file" error instead of "wrong index" error when we got a merge table with empty underlying tables list. In 5.1 we cannot rely on info->open_tables value when checking if a merge table has no underlying tables defined. Use info->tables instead. --- mysql-test/r/merge.result | 7 ++++++- mysql-test/t/merge.test | 9 ++++++++- storage/myisammrg/myrg_queue.c | 12 +++++++++++- 3 files changed, 25 insertions(+), 3 deletions(-) diff --git a/mysql-test/r/merge.result b/mysql-test/r/merge.result index ff9b1a84dbc..e46d8e75ab1 100644 --- a/mysql-test/r/merge.result +++ b/mysql-test/r/merge.result @@ -277,7 +277,7 @@ t3 CREATE TABLE `t3` ( drop table t3,t2,t1; create table t1 (a int not null, key(a)) engine=merge; select * from t1; -ERROR HY000: Got error 124 from storage engine +a drop table t1; create table t1 (a int not null, b int not null, key(a,b)); create table t2 (a int not null, b int not null, key(a,b)); @@ -988,6 +988,11 @@ m1 CREATE TABLE `m1` ( `a` int(11) DEFAULT NULL ) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 DROP TABLE t1, m1; +CREATE TABLE t1(a INT, KEY(a)) ENGINE=merge; +SELECT MAX(a) FROM t1; +MAX(a) +NULL +DROP TABLE t1; CREATE TABLE t1(a INT); CREATE TABLE t2(a VARCHAR(10)); CREATE TABLE m1(a INT) ENGINE=MERGE UNION=(t1, t2); diff --git a/mysql-test/t/merge.test b/mysql-test/t/merge.test index ab901185e43..a9d98da0403 100644 --- a/mysql-test/t/merge.test +++ b/mysql-test/t/merge.test @@ -126,7 +126,6 @@ drop table t3,t2,t1; # Test table without unions # create table t1 (a int not null, key(a)) engine=merge; ---error 1030 select * from t1; drop table t1; @@ -615,6 +614,14 @@ ALTER TABLE m1 UNION=(); SHOW CREATE TABLE m1; DROP TABLE t1, m1; +# +# BUG#35274 - merge table doesn't need any base tables, gives error 124 when +# key accessed +# +CREATE TABLE t1(a INT, KEY(a)) ENGINE=merge; +SELECT MAX(a) FROM t1; +DROP TABLE t1; + # # BUG#32047 - 'Spurious' errors while opening MERGE tables # diff --git a/storage/myisammrg/myrg_queue.c b/storage/myisammrg/myrg_queue.c index d2579053784..2c447083558 100644 --- a/storage/myisammrg/myrg_queue.c +++ b/storage/myisammrg/myrg_queue.c @@ -65,7 +65,17 @@ int _myrg_init_queue(MYRG_INFO *info,int inx,enum ha_rkey_function search_flag) } } else - my_errno= error= HA_ERR_WRONG_INDEX; + { + /* + inx may be bigger than info->keys if there are no underlying tables + defined. In this case we should return empty result. As we check for + underlying tables conformance when we open a table, we may not enter + this branch with underlying table that has less keys than merge table + have. + */ + DBUG_ASSERT(!info->tables); + error= my_errno= HA_ERR_END_OF_FILE; + } return error; }