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6675c2c2d3
optimizer does not honor IGNORE INDEX - Allow an index to be used for sorting the table instead of filesort only if it is not disabled by IGNORE INDEX. mysql-test/r/group_by.result: Bug #21174: Index degrades sort performance and optimizer does not honor IGNORE INDEX - test case mysql-test/t/group_by.test: Bug #21174: Index degrades sort performance and optimizer does not honor IGNORE INDEX - test case
832 lines
31 KiB
Text
832 lines
31 KiB
Text
drop table if exists t1,t2,t3;
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SELECT 1 FROM (SELECT 1) as a GROUP BY SUM(1);
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ERROR HY000: Invalid use of group function
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CREATE TABLE t1 (
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spID int(10) unsigned,
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userID int(10) unsigned,
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score smallint(5) unsigned,
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lsg char(40),
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date date
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);
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INSERT INTO t1 VALUES (1,1,1,'','0000-00-00');
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INSERT INTO t1 VALUES (2,2,2,'','0000-00-00');
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INSERT INTO t1 VALUES (2,1,1,'','0000-00-00');
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INSERT INTO t1 VALUES (3,3,3,'','0000-00-00');
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CREATE TABLE t2 (
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userID int(10) unsigned NOT NULL auto_increment,
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niName char(15),
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passwd char(8),
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mail char(50),
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isAukt enum('N','Y') DEFAULT 'N',
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vName char(30),
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nName char(40),
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adr char(60),
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plz char(5),
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ort char(35),
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land char(20),
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PRIMARY KEY (userID)
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);
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INSERT INTO t2 VALUES (1,'name','pass','mail','Y','v','n','adr','1','1','1');
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INSERT INTO t2 VALUES (2,'name','pass','mail','Y','v','n','adr','1','1','1');
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INSERT INTO t2 VALUES (3,'name','pass','mail','Y','v','n','adr','1','1','1');
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INSERT INTO t2 VALUES (4,'name','pass','mail','Y','v','n','adr','1','1','1');
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INSERT INTO t2 VALUES (5,'name','pass','mail','Y','v','n','adr','1','1','1');
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SELECT t2.userid, MIN(t1.score) FROM t1, t2 WHERE t1.userID=t2.userID GROUP BY t2.userid;
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userid MIN(t1.score)
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1 1
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2 2
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3 3
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SELECT t2.userid, MIN(t1.score) FROM t1, t2 WHERE t1.userID=t2.userID GROUP BY t2.userid ORDER BY NULL;
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userid MIN(t1.score)
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1 1
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2 2
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3 3
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SELECT t2.userid, MIN(t1.score) FROM t1, t2 WHERE t1.userID=t2.userID AND t1.spID=2 GROUP BY t2.userid;
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userid MIN(t1.score)
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1 1
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2 2
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SELECT t2.userid, MIN(t1.score+0.0) FROM t1, t2 WHERE t1.userID=t2.userID AND t1.spID=2 GROUP BY t2.userid;
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userid MIN(t1.score+0.0)
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1 1.0
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2 2.0
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SELECT t2.userid, MIN(t1.score+0.0) FROM t1, t2 WHERE t1.userID=t2.userID AND t1.spID=2 GROUP BY t2.userid ORDER BY NULL;
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userid MIN(t1.score+0.0)
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2 2.0
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1 1.0
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EXPLAIN SELECT t2.userid, MIN(t1.score+0.0) FROM t1, t2 WHERE t1.userID=t2.userID AND t1.spID=2 GROUP BY t2.userid ORDER BY NULL;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using where; Using temporary
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1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.userID 1 Using index
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drop table t1,t2;
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CREATE TABLE t1 (
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PID int(10) unsigned NOT NULL auto_increment,
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payDate date DEFAULT '0000-00-00' NOT NULL,
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recDate datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
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URID int(10) unsigned DEFAULT '0' NOT NULL,
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CRID int(10) unsigned DEFAULT '0' NOT NULL,
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amount int(10) unsigned DEFAULT '0' NOT NULL,
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operator int(10) unsigned,
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method enum('unknown','cash','dealer','check','card','lazy','delayed','test') DEFAULT 'unknown' NOT NULL,
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DIID int(10) unsigned,
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reason char(1) binary DEFAULT '' NOT NULL,
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code_id int(10) unsigned,
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qty mediumint(8) unsigned DEFAULT '0' NOT NULL,
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PRIMARY KEY (PID),
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KEY URID (URID),
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KEY reason (reason),
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KEY method (method),
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KEY payDate (payDate)
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);
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INSERT INTO t1 VALUES (1,'1970-01-01','1997-10-17 00:00:00',2529,1,21000,11886,'check',0,'F',16200,6);
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SELECT COUNT(P.URID),SUM(P.amount),P.method, MIN(PP.recdate+0) > 19980501000000 AS IsNew FROM t1 AS P JOIN t1 as PP WHERE P.URID = PP.URID GROUP BY method,IsNew;
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ERROR 42000: Can't group on 'IsNew'
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drop table t1;
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CREATE TABLE t1 (
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cid mediumint(9) NOT NULL auto_increment,
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firstname varchar(32) DEFAULT '' NOT NULL,
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surname varchar(32) DEFAULT '' NOT NULL,
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PRIMARY KEY (cid)
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);
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INSERT INTO t1 VALUES (1,'That','Guy');
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INSERT INTO t1 VALUES (2,'Another','Gent');
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CREATE TABLE t2 (
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call_id mediumint(8) NOT NULL auto_increment,
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contact_id mediumint(8) DEFAULT '0' NOT NULL,
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PRIMARY KEY (call_id),
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KEY contact_id (contact_id)
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);
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lock tables t1 read,t2 write;
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INSERT INTO t2 VALUES (10,2);
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INSERT INTO t2 VALUES (18,2);
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INSERT INTO t2 VALUES (62,2);
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INSERT INTO t2 VALUES (91,2);
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INSERT INTO t2 VALUES (92,2);
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SELECT cid, CONCAT(firstname, ' ', surname), COUNT(call_id) FROM t1 LEFT JOIN t2 ON cid=contact_id WHERE firstname like '%foo%' GROUP BY cid;
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cid CONCAT(firstname, ' ', surname) COUNT(call_id)
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SELECT cid, CONCAT(firstname, ' ', surname), COUNT(call_id) FROM t1 LEFT JOIN t2 ON cid=contact_id WHERE firstname like '%foo%' GROUP BY cid ORDER BY NULL;
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cid CONCAT(firstname, ' ', surname) COUNT(call_id)
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SELECT HIGH_PRIORITY cid, CONCAT(firstname, ' ', surname), COUNT(call_id) FROM t1 LEFT JOIN t2 ON cid=contact_id WHERE firstname like '%foo%' GROUP BY cid ORDER BY surname, firstname;
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cid CONCAT(firstname, ' ', surname) COUNT(call_id)
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drop table t1,t2;
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unlock tables;
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CREATE TABLE t1 (
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bug_id mediumint(9) NOT NULL auto_increment,
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groupset bigint(20) DEFAULT '0' NOT NULL,
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assigned_to mediumint(9) DEFAULT '0' NOT NULL,
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bug_file_loc text,
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bug_severity enum('blocker','critical','major','normal','minor','trivial','enhancement') DEFAULT 'blocker' NOT NULL,
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bug_status enum('','NEW','ASSIGNED','REOPENED','RESOLVED','VERIFIED','CLOSED') DEFAULT 'NEW' NOT NULL,
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creation_ts datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
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delta_ts timestamp,
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short_desc mediumtext,
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long_desc mediumtext,
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op_sys enum('All','Windows 3.1','Windows 95','Windows 98','Windows NT','Windows 2000','Linux','other') DEFAULT 'All' NOT NULL,
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priority enum('P1','P2','P3','P4','P5') DEFAULT 'P1' NOT NULL,
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product varchar(64) DEFAULT '' NOT NULL,
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rep_platform enum('All','PC','VTD-8','Other'),
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reporter mediumint(9) DEFAULT '0' NOT NULL,
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version varchar(16) DEFAULT '' NOT NULL,
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component varchar(50) DEFAULT '' NOT NULL,
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resolution enum('','FIXED','INVALID','WONTFIX','LATER','REMIND','DUPLICATE','WORKSFORME') DEFAULT '' NOT NULL,
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target_milestone varchar(20) DEFAULT '' NOT NULL,
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qa_contact mediumint(9) DEFAULT '0' NOT NULL,
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status_whiteboard mediumtext NOT NULL,
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votes mediumint(9) DEFAULT '0' NOT NULL,
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PRIMARY KEY (bug_id),
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KEY assigned_to (assigned_to),
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KEY creation_ts (creation_ts),
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KEY delta_ts (delta_ts),
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KEY bug_severity (bug_severity),
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KEY bug_status (bug_status),
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KEY op_sys (op_sys),
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KEY priority (priority),
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KEY product (product),
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KEY reporter (reporter),
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KEY version (version),
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KEY component (component),
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KEY resolution (resolution),
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KEY target_milestone (target_milestone),
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KEY qa_contact (qa_contact),
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KEY votes (votes)
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);
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INSERT INTO t1 VALUES (1,0,0,'','normal','','2000-02-10 09:25:12',20000321114747,'','','Linux','P1','TestProduct','PC',3,'other','TestComponent','','M1',0,'',0);
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INSERT INTO t1 VALUES (9,0,0,'','enhancement','','2000-03-10 11:49:36',20000321114747,'','','All','P5','AAAAA','PC',3,'2.00 CD - Pre','BBBBBBBBBBBBB - conversion','','',0,'',0);
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INSERT INTO t1 VALUES (10,0,0,'','enhancement','','2000-03-10 18:10:16',20000321114747,'','','All','P4','AAAAA','PC',3,'2.00 CD - Pre','BBBBBBBBBBBBB - conversion','','',0,'',0);
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INSERT INTO t1 VALUES (7,0,0,'','critical','','2000-03-09 10:50:21',20000321114747,'','','All','P1','AAAAA','PC',3,'2.00 CD - Pre','BBBBBBBBBBBBB - generic','','',0,'',0);
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INSERT INTO t1 VALUES (6,0,0,'','normal','','2000-03-09 10:42:44',20000321114747,'','','All','P2','AAAAA','PC',3,'2.00 CD - Pre','kkkkkkkkkkk lllllllllll','','',0,'',0);
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INSERT INTO t1 VALUES (8,0,0,'','major','','2000-03-09 11:32:14',20000321114747,'','','All','P3','AAAAA','PC',3,'2.00 CD - Pre','kkkkkkkkkkk lllllllllll','','',0,'',0);
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INSERT INTO t1 VALUES (5,0,0,'','enhancement','','2000-03-09 10:38:59',20000321114747,'','','All','P5','CCC/CCCCCC','PC',5,'7.00','Administration','','',0,'',0);
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INSERT INTO t1 VALUES (4,0,0,'','normal','','2000-03-08 18:32:14',20000321114747,'','','other','P2','TestProduct','Other',3,'other','TestComponent2','','',0,'',0);
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INSERT INTO t1 VALUES (3,0,0,'','normal','','2000-03-08 18:30:52',20000321114747,'','','other','P2','TestProduct','Other',3,'other','TestComponent','','',0,'',0);
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INSERT INTO t1 VALUES (2,0,0,'','enhancement','','2000-03-08 18:24:51',20000321114747,'','','All','P2','TestProduct','Other',4,'other','TestComponent2','','',0,'',0);
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INSERT INTO t1 VALUES (11,0,0,'','blocker','','2000-03-13 09:43:41',20000321114747,'','','All','P2','CCC/CCCCCC','PC',5,'7.00','DDDDDDDDD','','',0,'',0);
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INSERT INTO t1 VALUES (12,0,0,'','normal','','2000-03-13 16:14:31',20000321114747,'','','All','P2','AAAAA','PC',3,'2.00 CD - Pre','kkkkkkkkkkk lllllllllll','','',0,'',0);
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INSERT INTO t1 VALUES (13,0,0,'','normal','','2000-03-15 16:20:44',20000321114747,'','','other','P2','TestProduct','Other',3,'other','TestComponent','','',0,'',0);
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INSERT INTO t1 VALUES (14,0,0,'','blocker','','2000-03-15 18:13:47',20000321114747,'','','All','P1','AAAAA','PC',3,'2.00 CD - Pre','BBBBBBBBBBBBB - generic','','',0,'',0);
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INSERT INTO t1 VALUES (15,0,0,'','minor','','2000-03-16 18:03:28',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','DDDDDDDDD','','',0,'',0);
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INSERT INTO t1 VALUES (16,0,0,'','normal','','2000-03-16 18:33:41',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','Administration','','',0,'',0);
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INSERT INTO t1 VALUES (17,0,0,'','normal','','2000-03-16 18:34:18',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','Administration','','',0,'',0);
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INSERT INTO t1 VALUES (18,0,0,'','normal','','2000-03-16 18:34:56',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','Administration','','',0,'',0);
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INSERT INTO t1 VALUES (19,0,0,'','enhancement','','2000-03-16 18:35:34',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','Administration','','',0,'',0);
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INSERT INTO t1 VALUES (20,0,0,'','enhancement','','2000-03-16 18:36:23',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','Administration','','',0,'',0);
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INSERT INTO t1 VALUES (21,0,0,'','enhancement','','2000-03-16 18:37:23',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','Administration','','',0,'',0);
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INSERT INTO t1 VALUES (22,0,0,'','enhancement','','2000-03-16 18:38:16',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','Administration','','',0,'',0);
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INSERT INTO t1 VALUES (23,0,0,'','normal','','2000-03-16 18:58:12',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','DDDDDDDDD','','',0,'',0);
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INSERT INTO t1 VALUES (24,0,0,'','normal','','2000-03-17 11:08:10',20000321114747,'','','All','P2','AAAAAAAA-AAA','PC',3,'2.8','Web Interface','','',0,'',0);
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INSERT INTO t1 VALUES (25,0,0,'','normal','','2000-03-17 11:10:45',20000321114747,'','','All','P2','AAAAAAAA-AAA','PC',3,'2.8','Web Interface','','',0,'',0);
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INSERT INTO t1 VALUES (26,0,0,'','normal','','2000-03-17 11:15:47',20000321114747,'','','All','P2','AAAAAAAA-AAA','PC',3,'2.8','Web Interface','','',0,'',0);
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INSERT INTO t1 VALUES (27,0,0,'','normal','','2000-03-17 17:45:41',20000321114747,'','','All','P2','CCC/CCCCCC','PC',5,'7.00','DDDDDDDDD','','',0,'',0);
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INSERT INTO t1 VALUES (28,0,0,'','normal','','2000-03-20 09:51:45',20000321114747,'','','Windows NT','P2','TestProduct','PC',8,'other','TestComponent','','',0,'',0);
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INSERT INTO t1 VALUES (29,0,0,'','normal','','2000-03-20 11:15:09',20000321114747,'','','All','P5','AAAAAAAA-AAA','PC',3,'2.8','Web Interface','','',0,'',0);
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CREATE TABLE t2 (
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value tinytext,
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program varchar(64),
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initialowner tinytext NOT NULL,
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initialqacontact tinytext NOT NULL,
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description mediumtext NOT NULL
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);
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INSERT INTO t2 VALUES ('TestComponent','TestProduct','id0001','','');
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INSERT INTO t2 VALUES ('BBBBBBBBBBBBB - conversion','AAAAA','id0001','','');
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INSERT INTO t2 VALUES ('BBBBBBBBBBBBB - generic','AAAAA','id0001','','');
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INSERT INTO t2 VALUES ('TestComponent2','TestProduct','id0001','','');
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INSERT INTO t2 VALUES ('BBBBBBBBBBBBB - eeeeeeeee','AAAAA','id0001','','');
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INSERT INTO t2 VALUES ('kkkkkkkkkkk lllllllllll','AAAAA','id0001','','');
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INSERT INTO t2 VALUES ('Test Procedures','AAAAA','id0001','','');
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INSERT INTO t2 VALUES ('Documentation','AAAAA','id0003','','');
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INSERT INTO t2 VALUES ('DDDDDDDDD','CCC/CCCCCC','id0002','','');
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INSERT INTO t2 VALUES ('Eeeeeeee Lite','CCC/CCCCCC','id0002','','');
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INSERT INTO t2 VALUES ('Eeeeeeee Full','CCC/CCCCCC','id0002','','');
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INSERT INTO t2 VALUES ('Administration','CCC/CCCCCC','id0002','','');
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INSERT INTO t2 VALUES ('Distribution','CCC/CCCCCC','id0002','','');
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INSERT INTO t2 VALUES ('Setup','CCC/CCCCCC','id0002','','');
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INSERT INTO t2 VALUES ('Unspecified','CCC/CCCCCC','id0002','','');
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INSERT INTO t2 VALUES ('Web Interface','AAAAAAAA-AAA','id0001','','');
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INSERT INTO t2 VALUES ('Host communication','AAAAA','id0001','','');
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select value,description,bug_id from t2 left join t1 on t2.program=t1.product and t2.value=t1.component where program="AAAAA";
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value description bug_id
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BBBBBBBBBBBBB - conversion 9
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BBBBBBBBBBBBB - conversion 10
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BBBBBBBBBBBBB - generic 7
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BBBBBBBBBBBBB - generic 14
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BBBBBBBBBBBBB - eeeeeeeee NULL
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kkkkkkkkkkk lllllllllll 6
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kkkkkkkkkkk lllllllllll 8
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kkkkkkkkkkk lllllllllll 12
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Test Procedures NULL
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Documentation NULL
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Host communication NULL
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select value,description,COUNT(bug_id) from t2 left join t1 on t2.program=t1.product and t2.value=t1.component where program="AAAAA" group by value;
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value description COUNT(bug_id)
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BBBBBBBBBBBBB - conversion 2
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BBBBBBBBBBBBB - eeeeeeeee 0
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BBBBBBBBBBBBB - generic 2
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Documentation 0
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Host communication 0
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kkkkkkkkkkk lllllllllll 3
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Test Procedures 0
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select value,description,COUNT(bug_id) from t2 left join t1 on t2.program=t1.product and t2.value=t1.component where program="AAAAA" group by value having COUNT(bug_id) IN (0,2);
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value description COUNT(bug_id)
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BBBBBBBBBBBBB - conversion 2
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BBBBBBBBBBBBB - eeeeeeeee 0
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BBBBBBBBBBBBB - generic 2
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Documentation 0
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Host communication 0
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Test Procedures 0
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drop table t1,t2;
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create table t1 (foo int);
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insert into t1 values (1);
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select 1+1, "a",count(*) from t1 where foo in (2);
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1+1 a count(*)
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2 a 0
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insert into t1 values (1);
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select 1+1,"a",count(*) from t1 where foo in (2);
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1+1 a count(*)
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2 a 0
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drop table t1;
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CREATE TABLE t1 (
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spID int(10) unsigned,
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userID int(10) unsigned,
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score smallint(5) unsigned,
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key (spid),
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key (score)
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);
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INSERT INTO t1 VALUES (1,1,1),(2,2,2),(2,1,1),(3,3,3),(4,3,3),(5,3,3),(6,3,3),(7,3,3);
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explain select userid,count(*) from t1 group by userid desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 8 Using temporary; Using filesort
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explain select userid,count(*) from t1 group by userid desc order by null;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 8 Using temporary
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select userid,count(*) from t1 group by userid desc;
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userid count(*)
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3 5
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2 1
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1 2
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select userid,count(*) from t1 group by userid desc having (count(*)+1) IN (4,3);
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userid count(*)
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1 2
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select userid,count(*) from t1 group by userid desc having 3 IN (1,COUNT(*));
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userid count(*)
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explain select spid,count(*) from t1 where spid between 1 and 2 group by spid desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range spID spID 5 NULL 3 Using where; Using index
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explain select spid,count(*) from t1 where spid between 1 and 2 group by spid;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range spID spID 5 NULL 3 Using where; Using index
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explain select spid,count(*) from t1 where spid between 1 and 2 group by spid order by null;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range spID spID 5 NULL 3 Using where; Using index
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select spid,count(*) from t1 where spid between 1 and 2 group by spid;
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spid count(*)
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1 1
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2 2
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select spid,count(*) from t1 where spid between 1 and 2 group by spid desc;
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spid count(*)
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2 2
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1 1
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explain extended select sql_big_result spid,sum(userid) from t1 group by spid desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 8 Using filesort
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Warnings:
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Note 1003 select sql_big_result `test`.`t1`.`spID` AS `spid`,sum(`test`.`t1`.`userID`) AS `sum(userid)` from `test`.`t1` group by `test`.`t1`.`spID` desc
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explain select sql_big_result spid,sum(userid) from t1 group by spid desc order by null;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 8 Using filesort
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select sql_big_result spid,sum(userid) from t1 group by spid desc;
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spid sum(userid)
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7 3
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6 3
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5 3
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4 3
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3 3
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2 3
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1 1
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explain select sql_big_result score,count(*) from t1 group by score desc;
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|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL score 3 NULL 8 Using index
|
|
explain select sql_big_result score,count(*) from t1 group by score desc order by null;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL score 3 NULL 8 Using index
|
|
select sql_big_result score,count(*) from t1 group by score desc;
|
|
score count(*)
|
|
3 5
|
|
2 1
|
|
1 2
|
|
drop table t1;
|
|
create table t1 (a date default null, b date default null);
|
|
insert t1 values ('1999-10-01','2000-01-10'), ('1997-01-01','1998-10-01');
|
|
select a,min(b) c,count(distinct rand()) from t1 group by a having c<a + interval 1 day;
|
|
a c count(distinct rand())
|
|
drop table t1;
|
|
CREATE TABLE t1 (a char(1));
|
|
INSERT INTO t1 VALUES ('A'),('B'),('A'),('B'),('A'),('B'),(NULL),('a'),('b'),(NULL),('A'),('B'),(NULL);
|
|
SELECT a FROM t1 GROUP BY a;
|
|
a
|
|
NULL
|
|
A
|
|
B
|
|
SELECT a,count(*) FROM t1 GROUP BY a;
|
|
a count(*)
|
|
NULL 3
|
|
A 5
|
|
B 5
|
|
SELECT a FROM t1 GROUP BY binary a;
|
|
a
|
|
NULL
|
|
A
|
|
B
|
|
a
|
|
b
|
|
SELECT a,count(*) FROM t1 GROUP BY binary a;
|
|
a count(*)
|
|
NULL 3
|
|
A 4
|
|
B 4
|
|
a 1
|
|
b 1
|
|
SELECT binary a FROM t1 GROUP BY 1;
|
|
binary a
|
|
NULL
|
|
A
|
|
B
|
|
a
|
|
b
|
|
SELECT binary a,count(*) FROM t1 GROUP BY 1;
|
|
binary a count(*)
|
|
NULL 3
|
|
A 4
|
|
B 4
|
|
a 1
|
|
b 1
|
|
SET SQL_BIG_TABLES=1;
|
|
SELECT a FROM t1 GROUP BY a;
|
|
a
|
|
NULL
|
|
A
|
|
B
|
|
SELECT a,count(*) FROM t1 GROUP BY a;
|
|
a count(*)
|
|
NULL 3
|
|
A 5
|
|
B 5
|
|
SELECT a FROM t1 GROUP BY binary a;
|
|
a
|
|
NULL
|
|
A
|
|
B
|
|
a
|
|
b
|
|
SELECT a,count(*) FROM t1 GROUP BY binary a;
|
|
a count(*)
|
|
NULL 3
|
|
A 4
|
|
B 4
|
|
a 1
|
|
b 1
|
|
SELECT binary a FROM t1 GROUP BY 1;
|
|
binary a
|
|
NULL
|
|
A
|
|
B
|
|
a
|
|
b
|
|
SELECT binary a,count(*) FROM t1 GROUP BY 1;
|
|
binary a count(*)
|
|
NULL 3
|
|
A 4
|
|
B 4
|
|
a 1
|
|
b 1
|
|
SET SQL_BIG_TABLES=0;
|
|
drop table t1;
|
|
CREATE TABLE t1 (
|
|
`a` char(193) default NULL,
|
|
`b` char(63) default NULL
|
|
);
|
|
INSERT INTO t1 VALUES ('abc','def'),('hij','klm');
|
|
SELECT CONCAT(a, b) FROM t1 GROUP BY 1;
|
|
CONCAT(a, b)
|
|
abcdef
|
|
hijklm
|
|
SELECT CONCAT(a, b),count(*) FROM t1 GROUP BY 1;
|
|
CONCAT(a, b) count(*)
|
|
abcdef 1
|
|
hijklm 1
|
|
SELECT CONCAT(a, b),count(distinct a) FROM t1 GROUP BY 1;
|
|
CONCAT(a, b) count(distinct a)
|
|
abcdef 1
|
|
hijklm 1
|
|
SELECT 1 FROM t1 GROUP BY CONCAT(a, b);
|
|
1
|
|
1
|
|
1
|
|
INSERT INTO t1 values ('hij','klm');
|
|
SELECT CONCAT(a, b),count(*) FROM t1 GROUP BY 1;
|
|
CONCAT(a, b) count(*)
|
|
abcdef 1
|
|
hijklm 2
|
|
DROP TABLE t1;
|
|
create table t1 (One int unsigned, Two int unsigned, Three int unsigned, Four int unsigned);
|
|
insert into t1 values (1,2,1,4),(1,2,2,4),(1,2,3,4),(1,2,4,4),(1,1,1,4),(1,1,2,4),(1,1,3,4),(1,1,4,4),(1,3,1,4),(1,3,2,4),(1,3,3,4),(1,3,4,4);
|
|
select One, Two, sum(Four) from t1 group by One,Two;
|
|
One Two sum(Four)
|
|
1 1 16
|
|
1 2 16
|
|
1 3 16
|
|
drop table t1;
|
|
create table t1 (id integer primary key not null auto_increment, gender char(1));
|
|
insert into t1 values (NULL, 'M'), (NULL, 'F'),(NULL, 'F'),(NULL, 'F'),(NULL, 'M');
|
|
create table t2 (user_id integer not null, date date);
|
|
insert into t2 values (1, '2002-06-09'),(2, '2002-06-09'),(1, '2002-06-09'),(3, '2002-06-09'),(4, '2002-06-09'),(4, '2002-06-09');
|
|
select u.gender as gender, count(distinct u.id) as dist_count, (count(distinct u.id)/5*100) as percentage from t1 u, t2 l where l.user_id = u.id group by u.gender;
|
|
gender dist_count percentage
|
|
F 3 60.0000
|
|
M 1 20.0000
|
|
select u.gender as gender, count(distinct u.id) as dist_count, (count(distinct u.id)/5*100) as percentage from t1 u, t2 l where l.user_id = u.id group by u.gender order by percentage;
|
|
gender dist_count percentage
|
|
M 1 20.0000
|
|
F 3 60.0000
|
|
drop table t1,t2;
|
|
CREATE TABLE t1 (ID1 int, ID2 int, ID int NOT NULL AUTO_INCREMENT,PRIMARY KEY(ID
|
|
));
|
|
insert into t1 values (1,244,NULL),(2,243,NULL),(134,223,NULL),(185,186,NULL);
|
|
select S.ID as xID, S.ID1 as xID1 from t1 as S left join t1 as yS on S.ID1 between yS.ID1 and yS.ID2;
|
|
xID xID1
|
|
1 1
|
|
2 2
|
|
2 2
|
|
3 134
|
|
3 134
|
|
3 134
|
|
4 185
|
|
4 185
|
|
4 185
|
|
4 185
|
|
select S.ID as xID, S.ID1 as xID1, repeat('*',count(distinct yS.ID)) as Level from t1 as S left join t1 as yS on S.ID1 between yS.ID1 and yS.ID2 group by xID order by xID1;
|
|
xID xID1 Level
|
|
1 1 *
|
|
2 2 **
|
|
3 134 ***
|
|
4 185 ****
|
|
drop table t1;
|
|
CREATE TABLE t1 (
|
|
pid int(11) unsigned NOT NULL default '0',
|
|
c1id int(11) unsigned default NULL,
|
|
c2id int(11) unsigned default NULL,
|
|
value int(11) unsigned NOT NULL default '0',
|
|
UNIQUE KEY pid2 (pid,c1id,c2id),
|
|
UNIQUE KEY pid (pid,value)
|
|
) ENGINE=MyISAM;
|
|
INSERT INTO t1 VALUES (1, 1, NULL, 1),(1, 2, NULL, 2),(1, NULL, 3, 3),(1, 4, NULL, 4),(1, 5, NULL, 5);
|
|
CREATE TABLE t2 (
|
|
id int(11) unsigned NOT NULL default '0',
|
|
active enum('Yes','No') NOT NULL default 'Yes',
|
|
PRIMARY KEY (id)
|
|
) ENGINE=MyISAM;
|
|
INSERT INTO t2 VALUES (1, 'Yes'),(2, 'No'),(4, 'Yes'),(5, 'No');
|
|
CREATE TABLE t3 (
|
|
id int(11) unsigned NOT NULL default '0',
|
|
active enum('Yes','No') NOT NULL default 'Yes',
|
|
PRIMARY KEY (id)
|
|
);
|
|
INSERT INTO t3 VALUES (3, 'Yes');
|
|
select * from t1 AS m LEFT JOIN t2 AS c1 ON m.c1id =
|
|
c1.id AND c1.active = 'Yes' LEFT JOIN t3 AS c2 ON m.c2id = c2.id AND
|
|
c2.active = 'Yes' WHERE m.pid=1 AND (c1.id IS NOT NULL OR c2.id IS NOT NULL);
|
|
pid c1id c2id value id active id active
|
|
1 1 NULL 1 1 Yes NULL NULL
|
|
1 NULL 3 3 NULL NULL 3 Yes
|
|
1 4 NULL 4 4 Yes NULL NULL
|
|
select max(value) from t1 AS m LEFT JOIN t2 AS c1 ON
|
|
m.c1id = c1.id AND c1.active = 'Yes' LEFT JOIN t3 AS c2 ON m.c2id =
|
|
c2.id AND c2.active = 'Yes' WHERE m.pid=1 AND (c1.id IS NOT NULL OR c2.id IS
|
|
NOT NULL);
|
|
max(value)
|
|
4
|
|
drop table t1,t2,t3;
|
|
create table t1 (a blob null);
|
|
insert into t1 values (NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(""),(""),(""),("b");
|
|
select a,count(*) from t1 group by a;
|
|
a count(*)
|
|
NULL 9
|
|
3
|
|
b 1
|
|
set option sql_big_tables=1;
|
|
select a,count(*) from t1 group by a;
|
|
a count(*)
|
|
NULL 9
|
|
3
|
|
b 1
|
|
drop table t1;
|
|
create table t1 (a int not null, b int not null);
|
|
insert into t1 values (1,1),(1,2),(3,1),(3,2),(2,2),(2,1);
|
|
create table t2 (a int not null, b int not null, key(a));
|
|
insert into t2 values (1,3),(3,1),(2,2),(1,1);
|
|
select t1.a,t2.b from t1,t2 where t1.a=t2.a group by t1.a,t2.b;
|
|
a b
|
|
1 1
|
|
1 3
|
|
2 2
|
|
3 1
|
|
select t1.a,t2.b from t1,t2 where t1.a=t2.a group by t1.a,t2.b ORDER BY NULL;
|
|
a b
|
|
1 3
|
|
3 1
|
|
2 2
|
|
1 1
|
|
explain select t1.a,t2.b from t1,t2 where t1.a=t2.a group by t1.a,t2.b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 6 Using temporary; Using filesort
|
|
1 SIMPLE t2 ALL a NULL NULL NULL 3 Using where
|
|
explain select t1.a,t2.b from t1,t2 where t1.a=t2.a group by t1.a,t2.b ORDER BY NULL;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 6 Using temporary
|
|
1 SIMPLE t2 ALL a NULL NULL NULL 3 Using where
|
|
drop table t1,t2;
|
|
create table t1 (a int, b int);
|
|
insert into t1 values (1, 4),(10, 40),(1, 4),(10, 43),(1, 4),(10, 41),(1, 4),(10, 43),(1, 4);
|
|
select a, MAX(b), INTERVAL (MAX(b), 1,3,10,30,39,40,50,60,100,1000) from t1 group by a;
|
|
a MAX(b) INTERVAL (MAX(b), 1,3,10,30,39,40,50,60,100,1000)
|
|
1 4 2
|
|
10 43 6
|
|
select a, MAX(b), CASE MAX(b) when 4 then 4 when 43 then 43 else 0 end from t1 group by a;
|
|
a MAX(b) CASE MAX(b) when 4 then 4 when 43 then 43 else 0 end
|
|
1 4 4
|
|
10 43 43
|
|
select a, MAX(b), FIELD(MAX(b), '43', '4', '5') from t1 group by a;
|
|
a MAX(b) FIELD(MAX(b), '43', '4', '5')
|
|
1 4 2
|
|
10 43 1
|
|
select a, MAX(b), CONCAT_WS(MAX(b), '43', '4', '5') from t1 group by a;
|
|
a MAX(b) CONCAT_WS(MAX(b), '43', '4', '5')
|
|
1 4 434445
|
|
10 43 43434435
|
|
select a, MAX(b), ELT(MAX(b), 'a', 'b', 'c', 'd', 'e', 'f') from t1 group by a;
|
|
a MAX(b) ELT(MAX(b), 'a', 'b', 'c', 'd', 'e', 'f')
|
|
1 4 d
|
|
10 43 NULL
|
|
select a, MAX(b), MAKE_SET(MAX(b), 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h') from t1 group by a;
|
|
a MAX(b) MAKE_SET(MAX(b), 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h')
|
|
1 4 c
|
|
10 43 a,b,d,f
|
|
drop table t1;
|
|
create table t1 (id int not null, qty int not null);
|
|
insert into t1 values (1,2),(1,3),(2,4),(2,5);
|
|
select id, sum(qty) as sqty, count(qty) as cqty from t1 group by id having sum(qty)>2 and cqty>1;
|
|
id sqty cqty
|
|
1 5 2
|
|
2 9 2
|
|
select id, sum(qty) as sqty from t1 group by id having sqty>2 and count(qty)>1;
|
|
id sqty
|
|
1 5
|
|
2 9
|
|
select id, sum(qty) as sqty, count(qty) as cqty from t1 group by id having sqty>2 and cqty>1;
|
|
id sqty cqty
|
|
1 5 2
|
|
2 9 2
|
|
select id, sum(qty) as sqty, count(qty) as cqty from t1 group by id having sum(qty)>2 and count(qty)>1;
|
|
id sqty cqty
|
|
1 5 2
|
|
2 9 2
|
|
select count(*), case interval(qty,2,3,4,5,6,7,8) when -1 then NULL when 0 then "zero" when 1 then "one" when 2 then "two" end as category from t1 group by category;
|
|
count(*) category
|
|
2 NULL
|
|
1 one
|
|
1 two
|
|
select count(*), interval(qty,2,3,4,5,6,7,8) as category from t1 group by category;
|
|
count(*) category
|
|
1 1
|
|
1 2
|
|
1 3
|
|
1 4
|
|
drop table t1;
|
|
CREATE TABLE t1 (
|
|
userid int(10) unsigned,
|
|
score smallint(5) unsigned,
|
|
key (score)
|
|
);
|
|
INSERT INTO t1 VALUES (1,1),(2,2),(1,1),(3,3),(3,3),(3,3),(3,3),(3,3);
|
|
SELECT userid,count(*) FROM t1 GROUP BY userid DESC;
|
|
userid count(*)
|
|
3 5
|
|
2 1
|
|
1 2
|
|
EXPLAIN SELECT userid,count(*) FROM t1 GROUP BY userid DESC;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 8 Using temporary; Using filesort
|
|
DROP TABLE t1;
|
|
CREATE TABLE t1 (
|
|
i int(11) default NULL,
|
|
j int(11) default NULL
|
|
);
|
|
INSERT INTO t1 VALUES (1,2),(2,3),(4,5),(3,5),(1,5),(23,5);
|
|
SELECT i, COUNT(DISTINCT(i)) FROM t1 GROUP BY j ORDER BY NULL;
|
|
i COUNT(DISTINCT(i))
|
|
1 1
|
|
2 1
|
|
4 4
|
|
explain SELECT i, COUNT(DISTINCT(i)) FROM t1 GROUP BY j ORDER BY NULL;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 6 Using filesort
|
|
DROP TABLE t1;
|
|
create table t1 (a int);
|
|
insert into t1 values(null);
|
|
select min(a) is null from t1;
|
|
min(a) is null
|
|
1
|
|
select min(a) is null or null from t1;
|
|
min(a) is null or null
|
|
1
|
|
select 1 and min(a) is null from t1;
|
|
1 and min(a) is null
|
|
1
|
|
drop table t1;
|
|
create table t1 ( col1 int, col2 int );
|
|
insert into t1 values (1,1),(1,2),(1,3),(2,1),(2,2);
|
|
select group_concat( distinct col1 ) as alias from t1
|
|
group by col2 having alias like '%';
|
|
alias
|
|
1,2
|
|
1,2
|
|
1
|
|
drop table t1;
|
|
create table t1 (a integer, b integer, c integer);
|
|
insert into t1 (a,b) values (1,2),(1,3),(2,5);
|
|
select a, 0.1*0+1 r2, sum(1) r1 from t1 where a = 1 group by a having r1>1 and r2=1;
|
|
a r2 r1
|
|
1 1.0 2
|
|
select a, round(rand(100)*10) r2, sum(1) r1 from t1 where a = 1 group by a having r1>1 and r2<=2;
|
|
a r2 r1
|
|
1 2 2
|
|
select a,sum(b) from t1 where a=1 group by c;
|
|
a sum(b)
|
|
1 5
|
|
select a*sum(b) from t1 where a=1 group by c;
|
|
a*sum(b)
|
|
5
|
|
select sum(a)*sum(b) from t1 where a=1 group by c;
|
|
sum(a)*sum(b)
|
|
10
|
|
select a,sum(b) from t1 where a=1 group by c having a=1;
|
|
a sum(b)
|
|
1 5
|
|
select a as d,sum(b) from t1 where a=1 group by c having d=1;
|
|
d sum(b)
|
|
1 5
|
|
select sum(a)*sum(b) as d from t1 where a=1 group by c having d > 0;
|
|
d
|
|
10
|
|
drop table t1;
|
|
create table t1(a int);
|
|
insert into t1 values (0),(1),(2),(3),(4),(5),(6),(8),(9);
|
|
create table t2 (
|
|
a int,
|
|
b varchar(200) NOT NULL,
|
|
c varchar(50) NOT NULL,
|
|
d varchar(100) NOT NULL,
|
|
primary key (a,b(132),c,d),
|
|
key a (a,b)
|
|
) charset=utf8;
|
|
insert into t2 select
|
|
x3.a, -- 3
|
|
concat('val-', x3.a + 3*x4.a), -- 12
|
|
concat('val-', @a:=x3.a + 3*x4.a + 12*C.a), -- 120
|
|
concat('val-', @a + 120*D.a)
|
|
from t1 x3, t1 x4, t1 C, t1 D where x3.a < 3 and x4.a < 4 and D.a < 4;
|
|
delete from t2 where a = 2 and b = 'val-2' order by a,b,c,d limit 30;
|
|
explain select c from t2 where a = 2 and b = 'val-2' group by c;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 ref PRIMARY,a PRIMARY 402 const,const 6 Using where
|
|
select c from t2 where a = 2 and b = 'val-2' group by c;
|
|
c
|
|
val-74
|
|
val-98
|
|
drop table t1,t2;
|
|
create table t1 (b int4 unsigned not null);
|
|
insert into t1 values(3000000000);
|
|
select * from t1;
|
|
b
|
|
3000000000
|
|
select min(b) from t1;
|
|
min(b)
|
|
3000000000
|
|
drop table t1;
|
|
CREATE TABLE t1 (id int PRIMARY KEY, user_id int, hostname longtext);
|
|
INSERT INTO t1 VALUES
|
|
(1, 7, 'cache-dtc-af05.proxy.aol.com'),
|
|
(2, 3, 'what.ever.com'),
|
|
(3, 7, 'cache-dtc-af05.proxy.aol.com'),
|
|
(4, 7, 'cache-dtc-af05.proxy.aol.com');
|
|
SELECT hostname, COUNT(DISTINCT user_id) as no FROM t1
|
|
WHERE hostname LIKE '%aol%'
|
|
GROUP BY hostname;
|
|
hostname no
|
|
cache-dtc-af05.proxy.aol.com 1
|
|
DROP TABLE t1;
|
|
CREATE TABLE t1 (a int, b int);
|
|
INSERT INTO t1 VALUES (1,2), (1,3);
|
|
SELECT a, b FROM t1 GROUP BY 'const';
|
|
a b
|
|
1 2
|
|
SELECT DISTINCT a, b FROM t1 GROUP BY 'const';
|
|
a b
|
|
1 2
|
|
DROP TABLE t1;
|
|
CREATE TABLE t1 (id INT, dt DATETIME);
|
|
INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
|
|
INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
|
|
INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
|
|
INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
|
|
SELECT dt DIV 1 AS f, id FROM t1 GROUP BY f;
|
|
f id
|
|
20050501123000 1
|
|
DROP TABLE t1;
|
|
CREATE TABLE t1 (id varchar(20) NOT NULL);
|
|
INSERT INTO t1 VALUES ('trans1'), ('trans2');
|
|
CREATE TABLE t2 (id varchar(20) NOT NULL, err_comment blob NOT NULL);
|
|
INSERT INTO t2 VALUES ('trans1', 'a problem');
|
|
SELECT COUNT(DISTINCT(t1.id)), LEFT(err_comment, 256) AS comment
|
|
FROM t1 LEFT JOIN t2 ON t1.id=t2.id GROUP BY comment;
|
|
COUNT(DISTINCT(t1.id)) comment
|
|
1 NULL
|
|
1 a problem
|
|
DROP TABLE t1, t2;
|
|
create table t1 (f1 date);
|
|
insert into t1 values('2005-06-06');
|
|
insert into t1 values('2005-06-06');
|
|
select date(left(f1+0,8)) from t1 group by 1;
|
|
date(left(f1+0,8))
|
|
2005-06-06
|
|
drop table t1;
|
|
CREATE TABLE t1 (n int);
|
|
INSERT INTO t1 VALUES (1);
|
|
SELECT n+1 AS n FROM t1 GROUP BY n;
|
|
n
|
|
2
|
|
Warnings:
|
|
Warning 1052 Column 'n' in group statement is ambiguous
|
|
DROP TABLE t1;
|
|
create table t1(f1 varchar(5) key);
|
|
insert into t1 values (1),(2);
|
|
select sql_buffer_result max(f1) is null from t1;
|
|
max(f1) is null
|
|
0
|
|
select sql_buffer_result max(f1)+1 from t1;
|
|
max(f1)+1
|
|
3
|
|
drop table t1;
|
|
create table t1 (c1 char(3), c2 char(3));
|
|
create table t2 (c3 char(3), c4 char(3));
|
|
insert into t1 values ('aaa', 'bb1'), ('aaa', 'bb2');
|
|
insert into t2 values ('aaa', 'bb1'), ('aaa', 'bb2');
|
|
select t1.c1 as c2 from t1, t2 where t1.c2 = t2.c4
|
|
group by c2;
|
|
c2
|
|
aaa
|
|
aaa
|
|
Warnings:
|
|
Warning 1052 Column 'c2' in group statement is ambiguous
|
|
show warnings;
|
|
Level Code Message
|
|
Warning 1052 Column 'c2' in group statement is ambiguous
|
|
select t1.c1 as c2 from t1, t2 where t1.c2 = t2.c4
|
|
group by t1.c1;
|
|
c2
|
|
aaa
|
|
show warnings;
|
|
Level Code Message
|
|
drop table t1, t2;
|
|
CREATE TABLE t1 (a tinyint(3), b varchar(255), PRIMARY KEY (a));
|
|
INSERT INTO t1 VALUES (1,'-----'), (6,'Allemagne'), (17,'Autriche'),
|
|
(25,'Belgique'), (54,'Danemark'), (62,'Espagne'), (68,'France');
|
|
CREATE TABLE t2 (a tinyint(3), b tinyint(3), PRIMARY KEY (a), KEY b (b));
|
|
INSERT INTO t2 VALUES (1,1), (2,1), (6,6), (18,17), (15,25), (16,25),
|
|
(17,25), (10,54), (5,62),(3,68);
|
|
CREATE VIEW v1 AS select t1.a, concat(t1.b,'') AS b, t1.b as real_b from t1;
|
|
explain
|
|
SELECT straight_join sql_no_cache v1.a, v1.b, v1.real_b from t2, v1
|
|
where t2.b=v1.a GROUP BY t2.b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t2 index b b 2 NULL 10 Using index
|
|
1 PRIMARY t1 eq_ref PRIMARY PRIMARY 1 test.t2.b 1
|
|
SELECT straight_join sql_no_cache v1.a, v1.b, v1.real_b from t2, v1
|
|
where t2.b=v1.a GROUP BY t2.b;
|
|
a b real_b
|
|
1 ----- -----
|
|
6 Allemagne Allemagne
|
|
17 Autriche Autriche
|
|
25 Belgique Belgique
|
|
54 Danemark Danemark
|
|
62 Espagne Espagne
|
|
68 France France
|
|
DROP VIEW v1;
|
|
DROP TABLE t1,t2;
|
|
CREATE TABLE t1 (a INT, b INT, KEY(a));
|
|
INSERT INTO t1 VALUES (1, 1), (2, 2), (3,3), (4,4);
|
|
EXPLAIN SELECT a, SUM(b) FROM t1 GROUP BY a LIMIT 2;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL a 5 NULL 4
|
|
EXPLAIN SELECT a, SUM(b) FROM t1 IGNORE INDEX (a) GROUP BY a LIMIT 2;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using temporary; Using filesort
|
|
DROP TABLE t1;
|