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drop table if exists t1,t2;
create table t1 (a int not null auto_increment, b int not null, primary key(a));
insert into t1 (b) values (2),(3),(5),(5),(5),(6),(7),(9);
select SQL_CALC_FOUND_ROWS * from t1;
a b
1 2
2 3
3 5
4 5
5 5
6 6
7 7
8 9
select found_rows();
FOUND_ROWS()
8
select SQL_CALC_FOUND_ROWS * from t1 limit 1;
a b
1 2
select found_rows();
FOUND_ROWS()
8
select SQL_BUFFER_RESULT SQL_CALC_FOUND_ROWS * from t1 limit 1;
a b
1 2
select found_rows();
FOUND_ROWS()
8
select SQL_CALC_FOUND_ROWS * from t1 order by b desc limit 1;
a b
8 9
select found_rows();
FOUND_ROWS()
8
select SQL_CALC_FOUND_ROWS distinct b from t1 limit 1;
b
2
select found_rows();
FOUND_ROWS()
6
select SQL_CALC_FOUND_ROWS b,count(*) as c from t1 group by b order by c desc limit 1;
b c
5 3
select found_rows();
FOUND_ROWS()
6
select SQL_CALC_FOUND_ROWS * from t1 left join t1 as t2 on (t1.b=t2.a) limit 2,1;
a b a b
3 5 5 5
select found_rows();
FOUND_ROWS()
8
drop table t1;
create table t1 (a int not null primary key);
insert into t1 values (1),(2),(3),(4),(5);
select sql_calc_found_rows a from t1 where a in (1,2,3) order by a desc limit 0,2;
a
3
2
select FOUND_ROWS();
FOUND_ROWS()
3
select sql_calc_found_rows a from t1 where a in (1,2,3) order by a+2 desc limit 0,2;
a
3
2
select FOUND_ROWS();
FOUND_ROWS()
5
drop table t1;
CREATE TABLE t1 (
`id` smallint(5) unsigned NOT NULL auto_increment,
`kid` smallint(5) unsigned NOT NULL default '0',
PRIMARY KEY (`id`),
KEY `kid` (`kid`)
);
CREATE TABLE t2 (
id smallint(5) unsigned NOT NULL auto_increment,
name varchar(50) NOT NULL default '',
email varchar(50) NOT NULL default '',
PRIMARY KEY (id),
UNIQUE KEY e_n (email,name)
);
INSERT INTO t2 VALUES (1,'name1','email1'),(2,'name2','email2'),(3,'name3','email3'),(4,'name4','email4'),(5,'name5','email5'),(6,'name6','email6'),(7,'name7','email7'),(8,'name8','email8'),(9,'name9','email9'),(10,'name10','email10'),(11,'name11','email11'),(12,'name12','email12'),(13,'name13','email13'),(14,'name14','email14'),(15,'name15','email15'),(16,'name16','email16'),(17,'name17','email17'),(18,'name18','email18'),(19,'name19','email19'),(20,'name20','email20'),(21,'name21','email21'),(22,'name22','email22'),(23,'name23','email23'),(24,'name24','email24'),(25,'name25','email25'),(26,'name26','email26'),(27,'name27','email27'),(28,'name28','email28'),(29,'name29','email29'),(30,'name30','email30'),(31,'name31','email31'),(32,'name32','email32'),(33,'name33','email33'),(34,'name34','email34'),(35,'name35','email35'),(36,'name36','email36'),(37,'name37','email37'),(38,'name38','email38'),(39,'name39','email39'),(40,'name40','email40'),(41,'name41','email41'),(42,'name42','email42'),(43,'name43','email43'),(44,'name44','email44'),(45,'name45','email45'),(46,'name46','email46'),(47,'name47','email47'),(48,'name48','email48'),(49,'name49','email49'),(50,'name50','email50'),(51,'name51','email51'),(52,'name52','email52'),(53,'name53','email53'),(54,'name54','email54'),(55,'name55','email55'),(56,'name56','email56'),(57,'name57','email57'),(58,'name58','email58'),(59,'name59','email59'),(60,'name60','email60'),(61,'name61','email61'),(62,'name62','email62'),(63,'name63','email63'),(64,'name64','email64'),(65,'name65','email65'),(66,'name66','email66'),(67,'name67','email67'),(68,'name68','email68'),(69,'name69','email69'),(70,'name70','email70'),(71,'name71','email71'),(72,'name72','email72'),(73,'name73','email73'),(74,'name74','email74'),(75,'name75','email75'),(76,'name76','email76'),(77,'name77','email77'),(78,'name78','email78'),(79,'name79','email79'),(80,'name80','email80'),(81,'name81','email81'),(82,'name82','email82'),(83,'name83','email83'),(84,'name84','email84'),(85,'name85','email85'),(86,'name86','email86'),(87,'name87','email87'),(88,'name88','email88'),(89,'name89','email89'),(90,'name90','email90'),(91,'name91','email91'),(92,'name92','email92'),(93,'name93','email93'),(94,'name94','email94'),(95,'name95','email95'),(96,'name96','email96'),(97,'name97','email97'),(98,'name98','email98'),(99,'name99','email99'),(100,'name100','email100'),(101,'name101','email101'),(102,'name102','email102'),(103,'name103','email103'),(104,'name104','email104'),(105,'name105','email105'),(106,'name106','email106'),(107,'name107','email107'),(108,'name108','email108'),(109,'name109','email109'),(110,'name110','email110'),(111,'name111','email111'),(112,'name112','email112'),(113,'name113','email113'),(114,'name114','email114'),(115,'name115','email115'),(116,'name116','email116'),(117,'name117','email117'),(118,'name118','email118'),(119,'name119','email119'),(120,'name120','email120'),(121,'name121','email121'),(122,'name122','email122'),(123,'name123','email123'),(124,'name124','email124'),(125,'name125','email125'),(126,'name126','email126'),(127,'name127','email127'),(128,'name128','email128'),(129,'name129','email129'),(130,'name130','email130'),(131,'name131','email131'),(132,'name132','email132'),(133,'name133','email133'),(134,'name134','email134'),(135,'name135','email135'),(136,'name136','email136'),(137,'name137','email137'),(138,'name138','email138'),(139,'name139','email139'),(140,'name140','email140'),(141,'name141','email141'),(142,'name142','email142'),(143,'name143','email143'),(144,'name144','email144'),(145,'name145','email145'),(146,'name146','email146'),(147,'name147','email147'),(148,'name148','email148'),(149,'name149','email149'),(150,'name150','email150'),(151,'name151','email151'),(152,'name152','email152'),(153,'name153','email153'),(154,'name154','email154'),(155,'name155','email155'),(156,'name156','email156'),(157,'name157','email157'),(158,'name158','email158'),(159,'name159','email159'),(160,'name160','email160'),(161,'name161','email161'),(162,'name162','email162'),(163,'name163','email163'),(164,'name164','email164'),(165,'name165','email165'),(166,'name166','email166'),(167,'name167','email167'),(168,'name168','email168'),(169,'name169','email169'),(170,'name170','email170'),(171,'name171','email171'),(172,'name172','email172'),(173,'name173','email173'),(174,'name174','email174'),(175,'name175','email175'),(176,'name176','email176'),(177,'name177','email177'),(178,'name178','email178'),(179,'name179','email179'),(180,'name180','email180'),(181,'name181','email181'),(182,'name182','email182'),(183,'name183','email183'),(184,'name184','email184'),(185,'name185','email185'),(186,'name186','email186'),(187,'name187','email187'),(188,'name188','email188'),(189,'name189','email189'),(190,'name190','email190'),(191,'name191','email191'),(192,'name192','email192'),(193,'name193','email193'),(194,'name194','email194'),(195,'name195','email195'),(196,'name196','email196'),(197,'name197','email197'),(198,'name198','email198'),(199,'name199','email199'),(200,'name200','email200');
SELECT SQL_CALC_FOUND_ROWS DISTINCT email FROM t2 LEFT JOIN t1 ON kid = t2.id WHERE t1.id IS NULL LIMIT 10;
email
email1
email10
email100
email101
email102
email103
email104
email105
email106
email107
SELECT FOUND_ROWS();
FOUND_ROWS()
200
SELECT SQL_CALC_FOUND_ROWS DISTINCT email FROM t2 LEFT JOIN t1 ON kid = t2.id WHERE t1.id IS NULL order by email LIMIT 10;
email
email1
email10
email100
email101
email102
email103
email104
email105
email106
email107
SELECT FOUND_ROWS();
FOUND_ROWS()
200
SELECT DISTINCT email FROM t2 LEFT JOIN t1 ON kid = t2.id WHERE t1.id IS NULL LIMIT 10;
email
email1
email2
email3
email4
email5
email6
email7
email8
email9
email10
SELECT DISTINCT email FROM t2 LEFT JOIN t1 ON kid = t2.id WHERE t1.id IS NULL ORDER BY email LIMIT 10;
email
email1
email10
email100
email101
email102
email103
email104
email105
email106
email107
INSERT INTO `t1` (`id`, `kid`) VALUES ('', '150');
SELECT SQL_CALC_FOUND_ROWS DISTINCT email FROM t2 LEFT JOIN t1 ON kid = t2.id WHERE t1.id IS NULL LIMIT 10;
email
email1
email2
email3
email4
email5
email6
email7
email8
email9
email10
SELECT FOUND_ROWS();
FOUND_ROWS()
199
drop table t1,t2;
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