func_group.result
上传用户:romrleung
上传日期:2022-05-23
资源大小:18897k
文件大小:30k
- drop table if exists t1,t2;
- create table t1 (grp int, a bigint unsigned, c char(10) not null);
- insert into t1 values (1,1,"a");
- insert into t1 values (2,2,"b");
- insert into t1 values (2,3,"c");
- insert into t1 values (3,4,"E");
- insert into t1 values (3,5,"C");
- insert into t1 values (3,6,"D");
- select a,c,sum(a) from t1 group by a;
- a c sum(a)
- 1 a 1
- 2 b 2
- 3 c 3
- 4 E 4
- 5 C 5
- 6 D 6
- select a,c,sum(a) from t1 where a > 10 group by a;
- a c sum(a)
- select sum(a) from t1 where a > 10;
- sum(a)
- NULL
- select a from t1 order by rand(10);
- a
- 2
- 6
- 1
- 3
- 5
- 4
- select distinct a from t1 order by rand(10);
- a
- 2
- 6
- 1
- 3
- 5
- 4
- select count(distinct a),count(distinct grp) from t1;
- count(distinct a) count(distinct grp)
- 6 3
- insert into t1 values (null,null,'');
- select count(distinct a),count(distinct grp) from t1;
- count(distinct a) count(distinct grp)
- 6 3
- select sum(all a),count(all a),avg(all a),std(all a),variance(all a),bit_or(all a),bit_and(all a),min(all a),max(all a),min(all c),max(all c) from t1;
- sum(all a) count(all a) avg(all a) std(all a) variance(all a) bit_or(all a) bit_and(all a) min(all a) max(all a) min(all c) max(all c)
- 21 6 3.5000 1.7078 2.9167 7 0 1 6 E
- select grp, sum(a),count(a),avg(a),std(a),variance(a),bit_or(a),bit_and(a),min(a),max(a),min(c),max(c) from t1 group by grp;
- grp sum(a) count(a) avg(a) std(a) variance(a) bit_or(a) bit_and(a) min(a) max(a) min(c) max(c)
- NULL NULL 0 NULL NULL NULL 0 18446744073709551615 NULL NULL
- 1 1 1 1.0000 0.0000 0.0000 1 1 1 1 a a
- 2 5 2 2.5000 0.5000 0.2500 3 2 2 3 b c
- 3 15 3 5.0000 0.8165 0.6667 7 4 4 6 C E
- select grp, sum(a)+count(a)+avg(a)+std(a)+variance(a)+bit_or(a)+bit_and(a)+min(a)+max(a)+min(c)+max(c) as sum from t1 group by grp;
- grp sum
- NULL NULL
- 1 7
- 2 20.25
- 3 45.483163247594
- create table t2 (grp int, a bigint unsigned, c char(10));
- insert into t2 select grp,max(a)+max(grp),max(c) from t1 group by grp;
- replace into t2 select grp, a, c from t1 limit 2,1;
- select * from t2;
- grp a c
- NULL NULL
- 1 2 a
- 2 5 c
- 3 9 E
- 2 3 c
- drop table t1,t2;
- CREATE TABLE t1 (id int(11),value1 float(10,2));
- INSERT INTO t1 VALUES (1,0.00),(1,1.00), (1,2.00), (2,10.00), (2,11.00), (2,12.00);
- CREATE TABLE t2 (id int(11),name char(20));
- INSERT INTO t2 VALUES (1,'Set One'),(2,'Set Two');
- select id, avg(value1), std(value1), variance(value1) from t1 group by id;
- id avg(value1) std(value1) variance(value1)
- 1 1.000000 0.816497 0.666667
- 2 11.000000 0.816497 0.666667
- select name, avg(value1), std(value1), variance(value1) from t1, t2 where t1.id = t2.id group by t1.id;
- name avg(value1) std(value1) variance(value1)
- Set One 1.000000 0.816497 0.666667
- Set Two 11.000000 0.816497 0.666667
- drop table t1,t2;
- create table t1 (id int not null);
- create table t2 (id int not null,rating int null);
- insert into t1 values(1),(2),(3);
- insert into t2 values(1, 3),(2, NULL),(2, NULL),(3, 2),(3, NULL);
- select t1.id, avg(rating) from t1 left join t2 on ( t1.id = t2.id ) group by t1.id;
- id avg(rating)
- 1 3.0000
- 2 NULL
- 3 2.0000
- drop table t1,t2;
- create table t1 (a smallint(6) primary key, c char(10), b text);
- INSERT INTO t1 VALUES (1,'1','1');
- INSERT INTO t1 VALUES (2,'2','2');
- INSERT INTO t1 VALUES (4,'4','4');
- select count(*) from t1;
- count(*)
- 3
- select count(*) from t1 where a = 1;
- count(*)
- 1
- select count(*) from t1 where a = 100;
- count(*)
- 0
- select count(*) from t1 where a >= 10;
- count(*)
- 0
- select count(a) from t1 where a = 1;
- count(a)
- 1
- select count(a) from t1 where a = 100;
- count(a)
- 0
- select count(a) from t1 where a >= 10;
- count(a)
- 0
- select count(b) from t1 where b >= 2;
- count(b)
- 2
- select count(b) from t1 where b >= 10;
- count(b)
- 0
- select count(c) from t1 where c = 10;
- count(c)
- 0
- drop table t1;
- CREATE TABLE t1 (d DATETIME, i INT);
- INSERT INTO t1 VALUES (NOW(), 1);
- SELECT COUNT(i), i, COUNT(i)*i FROM t1 GROUP BY i;
- COUNT(i) i COUNT(i)*i
- 1 1 1
- SELECT COUNT(i), (i+0), COUNT(i)*(i+0) FROM t1 GROUP BY i;
- COUNT(i) (i+0) COUNT(i)*(i+0)
- 1 1 1
- DROP TABLE t1;
- create table t1 (
- num float(5,2),
- user char(20)
- );
- insert into t1 values (10.3,'nem'),(20.53,'monty'),(30.23,'sinisa');
- insert into t1 values (30.13,'nem'),(20.98,'monty'),(10.45,'sinisa');
- insert into t1 values (5.2,'nem'),(8.64,'monty'),(11.12,'sinisa');
- select sum(num) from t1;
- sum(num)
- 147.58
- select sum(num) from t1 group by user;
- sum(num)
- 50.15
- 45.63
- 51.80
- drop table t1;
- create table t1 (a1 int, a2 char(3), key k1(a1), key k2(a2));
- insert into t1 values(10,'aaa'), (10,null), (10,'bbb'), (20,'zzz');
- create table t2(a1 char(3), a2 int, a3 real, key k1(a1), key k2(a2, a1));
- select * from t1;
- a1 a2
- 10 aaa
- 10 NULL
- 10 bbb
- 20 zzz
- select min(a2) from t1;
- min(a2)
- aaa
- select max(t1.a1), max(t2.a2) from t1, t2;
- max(t1.a1) max(t2.a2)
- NULL NULL
- select max(t1.a1) from t1, t2;
- max(t1.a1)
- NULL
- select max(t2.a2), max(t1.a1) from t1, t2;
- max(t2.a2) max(t1.a1)
- NULL NULL
- explain select min(a2) from t1;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- explain select max(t1.a1), max(t2.a2) from t1, t2;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL No matching min/max row
- insert into t2 values('AAA', 10, 0.5);
- insert into t2 values('BBB', 20, 1.0);
- select t1.a1, t1.a2, t2.a1, t2.a2 from t1,t2;
- a1 a2 a1 a2
- 10 aaa AAA 10
- 10 NULL AAA 10
- 10 bbb AAA 10
- 20 zzz AAA 10
- 10 aaa BBB 20
- 10 NULL BBB 20
- 10 bbb BBB 20
- 20 zzz BBB 20
- select max(t1.a1), max(t2.a1) from t1, t2 where t2.a2=9;
- max(t1.a1) max(t2.a1)
- NULL NULL
- select max(t2.a1), max(t1.a1) from t1, t2 where t2.a2=9;
- max(t2.a1) max(t1.a1)
- NULL NULL
- select t1.a1, t1.a2, t2.a1, t2.a2 from t1 left outer join t2 on t1.a1=10;
- a1 a2 a1 a2
- 10 aaa AAA 10
- 10 aaa BBB 20
- 10 NULL AAA 10
- 10 NULL BBB 20
- 10 bbb AAA 10
- 10 bbb BBB 20
- 20 zzz NULL NULL
- select max(t1.a2) from t1 left outer join t2 on t1.a1=10;
- max(t1.a2)
- zzz
- select max(t2.a1) from t2 left outer join t1 on t2.a2=10 where t2.a2=20;
- max(t2.a1)
- BBB
- select max(t2.a1) from t2 left outer join t1 on t2.a2=10 where t2.a2=10;
- max(t2.a1)
- AAA
- select max(t2.a1) from t1 left outer join t2 on t1.a2=t2.a1 and 1=0 where t2.a1='AAA';
- max(t2.a1)
- NULL
- select max(t1.a2),max(t2.a1) from t1 left outer join t2 on t1.a1=10;
- max(t1.a2) max(t2.a1)
- zzz BBB
- drop table t1,t2;
- CREATE TABLE t1 (a int, b int);
- select count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1;
- count(b) sum(b) avg(b) std(b) min(b) max(b) bit_and(b) bit_or(b)
- 0 NULL NULL NULL NULL NULL 18446744073709551615 0
- select a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1 group by a;
- a count(b) sum(b) avg(b) std(b) min(b) max(b) bit_and(b) bit_or(b)
- insert into t1 values (1,null);
- select a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1 group by a;
- a count(b) sum(b) avg(b) std(b) min(b) max(b) bit_and(b) bit_or(b)
- 1 0 NULL NULL NULL NULL NULL 18446744073709551615 0
- insert into t1 values (1,null);
- insert into t1 values (2,null);
- select a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1 group by a;
- a count(b) sum(b) avg(b) std(b) min(b) max(b) bit_and(b) bit_or(b)
- 1 0 NULL NULL NULL NULL NULL 18446744073709551615 0
- 2 0 NULL NULL NULL NULL NULL 18446744073709551615 0
- select SQL_BIG_RESULT a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1 group by a;
- a count(b) sum(b) avg(b) std(b) min(b) max(b) bit_and(b) bit_or(b)
- 1 0 NULL NULL NULL NULL NULL 18446744073709551615 0
- 2 0 NULL NULL NULL NULL NULL 18446744073709551615 0
- insert into t1 values (2,1);
- select a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1 group by a;
- a count(b) sum(b) avg(b) std(b) min(b) max(b) bit_and(b) bit_or(b)
- 1 0 NULL NULL NULL NULL NULL 18446744073709551615 0
- 2 1 1 1.0000 0.0000 1 1 1 1
- select SQL_BIG_RESULT a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1 group by a;
- a count(b) sum(b) avg(b) std(b) min(b) max(b) bit_and(b) bit_or(b)
- 1 0 NULL NULL NULL NULL NULL 18446744073709551615 0
- 2 1 1 1.0000 0.0000 1 1 1 1
- insert into t1 values (3,1);
- select a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1 group by a;
- a count(b) sum(b) avg(b) std(b) min(b) max(b) bit_and(b) bit_or(b)
- 1 0 NULL NULL NULL NULL NULL 18446744073709551615 0
- 2 1 1 1.0000 0.0000 1 1 1 1
- 3 1 1 1.0000 0.0000 1 1 1 1
- select SQL_BIG_RESULT a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b), bit_xor(b) from t1 group by a;
- a count(b) sum(b) avg(b) std(b) min(b) max(b) bit_and(b) bit_or(b) bit_xor(b)
- 1 0 NULL NULL NULL NULL NULL 18446744073709551615 0 0
- 2 1 1 1.0000 0.0000 1 1 1 1 1
- 3 1 1 1.0000 0.0000 1 1 1 1 1
- explain extended select SQL_BIG_RESULT a,count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b), bit_xor(b) from t1 group by a;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1 ALL NULL NULL NULL NULL 5 Using filesort
- Warnings:
- Note 1003 select sql_big_result test.t1.a AS `a`,count(test.t1.b) AS `count(b)`,sum(test.t1.b) AS `sum(b)`,avg(test.t1.b) AS `avg(b)`,std(test.t1.b) AS `std(b)`,min(test.t1.b) AS `min(b)`,max(test.t1.b) AS `max(b)`,bit_and(test.t1.b) AS `bit_and(b)`,bit_or(test.t1.b) AS `bit_or(b)`,bit_xor(test.t1.b) AS `bit_xor(b)` from test.t1 group by test.t1.a
- drop table t1;
- create table t1 (col int);
- insert into t1 values (-1), (-2), (-3);
- select bit_and(col), bit_or(col) from t1;
- bit_and(col) bit_or(col)
- 18446744073709551612 18446744073709551615
- select SQL_BIG_RESULT bit_and(col), bit_or(col) from t1 group by col;
- bit_and(col) bit_or(col)
- 18446744073709551613 18446744073709551613
- 18446744073709551614 18446744073709551614
- 18446744073709551615 18446744073709551615
- drop table t1;
- create table t1 (a int);
- select avg(2) from t1;
- avg(2)
- NULL
- drop table t1;
- create table t1(
- a1 char(3) primary key,
- a2 smallint,
- a3 char(3),
- a4 real,
- a5 date,
- key k1(a2,a3),
- key k2(a4 desc,a1),
- key k3(a5,a1)
- );
- create table t2(
- a1 char(3) primary key,
- a2 char(17),
- a3 char(2),
- a4 char(3),
- key k1(a3, a2),
- key k2(a4)
- );
- insert into t1 values('AME',0,'SEA',0.100,date'1942-02-19');
- insert into t1 values('HBR',1,'SEA',0.085,date'1948-03-05');
- insert into t1 values('BOT',2,'SEA',0.085,date'1951-11-29');
- insert into t1 values('BMC',3,'SEA',0.085,date'1958-09-08');
- insert into t1 values('TWU',0,'LAX',0.080,date'1969-10-05');
- insert into t1 values('BDL',0,'DEN',0.080,date'1960-11-27');
- insert into t1 values('DTX',1,'NYC',0.080,date'1961-05-04');
- insert into t1 values('PLS',1,'WDC',0.075,date'1949-01-02');
- insert into t1 values('ZAJ',2,'CHI',0.075,date'1960-06-15');
- insert into t1 values('VVV',2,'MIN',0.075,date'1959-06-28');
- insert into t1 values('GTM',3,'DAL',0.070,date'1977-09-23');
- insert into t1 values('SSJ',null,'CHI',null,date'1974-03-19');
- insert into t1 values('KKK',3,'ATL',null,null);
- insert into t1 values('XXX',null,'MIN',null,null);
- insert into t2 values('TKF','Seattle','WA','AME');
- insert into t2 values('LCC','Los Angeles','CA','TWU');
- insert into t2 values('DEN','Denver','CO','BDL');
- insert into t2 values('SDC','San Diego','CA','TWU');
- insert into t2 values('NOL','New Orleans','LA','GTM');
- insert into t2 values('LAK','Los Angeles','CA','TWU');
- select * from t1;
- a1 a2 a3 a4 a5
- AME 0 SEA 0.1 1942-02-19
- HBR 1 SEA 0.085 1948-03-05
- BOT 2 SEA 0.085 1951-11-29
- BMC 3 SEA 0.085 1958-09-08
- TWU 0 LAX 0.08 1969-10-05
- BDL 0 DEN 0.08 1960-11-27
- DTX 1 NYC 0.08 1961-05-04
- PLS 1 WDC 0.075 1949-01-02
- ZAJ 2 CHI 0.075 1960-06-15
- VVV 2 MIN 0.075 1959-06-28
- GTM 3 DAL 0.07 1977-09-23
- SSJ NULL CHI NULL 1974-03-19
- KKK 3 ATL NULL NULL
- XXX NULL MIN NULL NULL
- select * from t2;
- a1 a2 a3 a4
- TKF Seattle WA AME
- LCC Los Angeles CA TWU
- DEN Denver CO BDL
- SDC San Diego CA TWU
- NOL New Orleans LA GTM
- LAK Los Angeles CA TWU
- explain
- select min(a1) from t1;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(a1) from t1;
- min(a1)
- AME
- explain
- select max(a4) from t1;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select max(a4) from t1;
- max(a4)
- 0.1
- explain
- select min(a5), max(a5) from t1;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(a5), max(a5) from t1;
- min(a5) max(a5)
- 1942-02-19 1977-09-23
- explain
- select min(a3) from t1 where a2 = 2;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(a3) from t1 where a2 = 2;
- min(a3)
- CHI
- explain
- select min(a1), max(a1) from t1 where a4 = 0.080;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(a1), max(a1) from t1 where a4 = 0.080;
- min(a1) max(a1)
- BDL TWU
- explain
- select min(t1.a5), max(t2.a3) from t1, t2;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(t1.a5), max(t2.a3) from t1, t2;
- min(t1.a5) max(t2.a3)
- 1942-02-19 WA
- explain
- select min(t1.a3), max(t2.a2) from t1, t2 where t1.a2 = 0 and t2.a3 = 'CA';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(t1.a3), max(t2.a2) from t1, t2 where t1.a2 = 0 and t2.a3 = 'CA';
- min(t1.a3) max(t2.a2)
- DEN San Diego
- explain
- select min(a1) from t1 where a1 > 'KKK';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(a1) from t1 where a1 > 'KKK';
- min(a1)
- PLS
- explain
- select min(a1) from t1 where a1 >= 'KKK';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(a1) from t1 where a1 >= 'KKK';
- min(a1)
- KKK
- explain
- select max(a3) from t1 where a2 = 2 and a3 < 'SEA';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select max(a3) from t1 where a2 = 2 and a3 < 'SEA';
- max(a3)
- MIN
- explain
- select max(a5) from t1 where a5 < date'1970-01-01';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select max(a5) from t1 where a5 < date'1970-01-01';
- max(a5)
- 1969-10-05
- explain
- select max(a3) from t1 where a2 is null;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select max(a3) from t1 where a2 is null;
- max(a3)
- MIN
- explain
- select max(a3) from t1 where a2 = 0 and a3 between 'K' and 'Q';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select max(a3) from t1 where a2 = 0 and a3 between 'K' and 'Q';
- max(a3)
- LAX
- explain
- select min(a1), max(a1) from t1 where a1 between 'A' and 'P';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(a1), max(a1) from t1 where a1 between 'A' and 'P';
- min(a1) max(a1)
- AME KKK
- explain
- select max(a3) from t1 where a3 < 'SEA' and a2 = 2 and a3 <= 'MIN';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select max(a3) from t1 where a3 < 'SEA' and a2 = 2 and a3 <= 'MIN';
- max(a3)
- MIN
- explain
- select max(a3) from t1 where a3 = 'MIN' and a2 = 2;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select max(a3) from t1 where a3 = 'MIN' and a2 = 2;
- max(a3)
- MIN
- explain
- select max(a3) from t1 where a3 = 'DEN' and a2 = 2;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL No matching min/max row
- select max(a3) from t1 where a3 = 'DEN' and a2 = 2;
- max(a3)
- NULL
- explain
- select max(t1.a3), min(t2.a2) from t1, t2 where t1.a2 = 2 and t1.a3 < 'MIN' and t2.a3 = 'CA';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select max(t1.a3), min(t2.a2) from t1, t2 where t1.a2 = 2 and t1.a3 < 'MIN' and t2.a3 = 'CA';
- max(t1.a3) min(t2.a2)
- CHI Los Angeles
- explain
- select max(a3) from t1 where a2 is null and a2 = 2;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
- select max(a3) from t1 where a2 is null and a2 = 2;
- max(a3)
- NULL
- explain
- select max(a2) from t1 where a2 >= 1;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select max(a2) from t1 where a2 >= 1;
- max(a2)
- 3
- explain
- select min(a3) from t1 where a2 = 2 and a3 < 'SEA';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(a3) from t1 where a2 = 2 and a3 < 'SEA';
- min(a3)
- CHI
- explain
- select min(a3) from t1 where a2 = 4;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL No matching min/max row
- select min(a3) from t1 where a2 = 4;
- min(a3)
- NULL
- explain
- select min(a3) from t1 where a2 = 2 and a3 > 'SEA';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL No matching min/max row
- select min(a3) from t1 where a2 = 2 and a3 > 'SEA';
- min(a3)
- NULL
- explain
- select (min(a4)+max(a4))/2 from t1;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select (min(a4)+max(a4))/2 from t1;
- (min(a4)+max(a4))/2
- 0.085
- explain
- select min(a3) from t1 where 2 = a2;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(a3) from t1 where 2 = a2;
- min(a3)
- CHI
- explain
- select max(a3) from t1 where a2 = 2 and 'SEA' > a3;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select max(a3) from t1 where a2 = 2 and 'SEA' > a3;
- max(a3)
- MIN
- explain
- select max(a3) from t1 where a2 = 2 and 'SEA' < a3;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL No matching min/max row
- select max(a3) from t1 where a2 = 2 and 'SEA' < a3;
- max(a3)
- NULL
- explain
- select min(a3) from t1 where a2 = 2 and a3 >= 'CHI';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(a3) from t1 where a2 = 2 and a3 >= 'CHI';
- min(a3)
- CHI
- explain
- select min(a3) from t1 where a2 = 2 and a3 >= 'CHI' and a3 < 'SEA';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(a3) from t1 where a2 = 2 and a3 >= 'CHI' and a3 < 'SEA';
- min(a3)
- CHI
- explain
- select min(a3) from t1 where a2 = 2 and a3 >= 'CHI' and a3 = 'MIN';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(a3) from t1 where a2 = 2 and a3 >= 'CHI' and a3 = 'MIN';
- min(a3)
- MIN
- explain
- select min(a3) from t1 where a2 = 2 and a3 >= 'SEA' and a3 = 'MIN';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
- select min(a3) from t1 where a2 = 2 and a3 >= 'SEA' and a3 = 'MIN';
- min(a3)
- NULL
- explain
- select min(t1.a1), min(t2.a4) from t1,t2 where t1.a1 < 'KKK' and t2.a4 < 'KKK';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(t1.a1), min(t2.a4) from t1,t2 where t1.a1 < 'KKK' and t2.a4 < 'KKK';
- min(t1.a1) min(t2.a4)
- AME AME
- explain
- select min(a1) from t1 where a1 > 'KKK' or a1 < 'XXX';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1 range PRIMARY PRIMARY 0 NULL 15 Using where; Using index
- explain
- select min(a1) from t1 where a1 != 'KKK';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1 range PRIMARY PRIMARY 3 NULL 14 Using where; Using index
- explain
- select max(a3) from t1 where a2 < 2 and a3 < 'SEA';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1 range k1 k1 3 NULL 5 Using where; Using index
- explain
- select max(t1.a3), min(t2.a2) from t1, t2 where t1.a2 = 2 and t1.a3 < 'MIN' and t2.a3 > 'CA';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1 range k1 k1 7 NULL 1 Using where; Using index
- 1 SIMPLE t2 range k1 k1 3 NULL 4 Using where; Using index
- explain
- select min(a4 - 0.01) from t1;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1 index NULL k2 12 NULL 14 Using index
- explain
- select max(a4 + 0.01) from t1;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1 index NULL k2 12 NULL 14 Using index
- explain
- select min(a3) from t1 where (a2 +1 ) is null;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1 index NULL k1 7 NULL 14 Using where; Using index
- explain
- select min(a3) from t1 where (a2 + 1) = 2;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1 index NULL k1 7 NULL 14 Using where; Using index
- explain
- select min(a3) from t1 where 2 = (a2 + 1);
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1 index NULL k1 7 NULL 14 Using where; Using index
- explain
- select min(a2) from t1 where a2 < 2 * a2 - 8;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1 index NULL k1 7 NULL 14 Using where; Using index
- explain
- select min(a1) from t1 where a1 between a3 and 'KKK';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 14 Using where
- explain
- select min(a4) from t1 where (a4 + 0.01) between 0.07 and 0.08;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1 index NULL k2 12 NULL 14 Using where; Using index
- explain
- select concat(min(t1.a1),min(t2.a4)) from t1, t2 where t2.a4 <> 'AME';
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t2 range k2 k2 4 NULL 6 Using where; Using index
- 1 SIMPLE t1 index NULL PRIMARY 3 NULL 14 Using index
- drop table t1, t2;
- create table t1 (USR_ID integer not null, MAX_REQ integer not null, constraint PK_SEA_USER primary key (USR_ID)) engine=InnoDB;
- insert into t1 values (1, 3);
- select count(*) + MAX_REQ - MAX_REQ + MAX_REQ - MAX_REQ + MAX_REQ - MAX_REQ + MAX_REQ - MAX_REQ + MAX_REQ - MAX_REQ from t1 group by MAX_REQ;
- count(*) + MAX_REQ - MAX_REQ + MAX_REQ - MAX_REQ + MAX_REQ - MAX_REQ + MAX_REQ - MAX_REQ + MAX_REQ - MAX_REQ
- 1
- select Case When Count(*) < MAX_REQ Then 1 Else 0 End from t1 where t1.USR_ID = 1 group by MAX_REQ;
- Case When Count(*) < MAX_REQ Then 1 Else 0 End
- 1
- drop table t1;
- create table t1 (a char(10));
- insert into t1 values ('a'),('b'),('c');
- select coercibility(max(a)) from t1;
- coercibility(max(a))
- 2
- drop table t1;
- create table t1 (a char character set latin2);
- insert into t1 values ('a'),('b');
- select charset(max(a)), coercibility(max(a)),
- charset(min(a)), coercibility(min(a)) from t1;
- charset(max(a)) coercibility(max(a)) charset(min(a)) coercibility(min(a))
- latin2 2 latin2 2
- create table t2 select max(a),min(a) from t1;
- show create table t2;
- Table Create Table
- t2 CREATE TABLE `t2` (
- `max(a)` char(1) character set latin2 default NULL,
- `min(a)` char(1) character set latin2 default NULL
- ) ENGINE=MyISAM DEFAULT CHARSET=latin1
- drop table t2,t1;
- create table t1 (a int);
- insert into t1 values (1);
- select max(a) as b from t1 having b=1;
- b
- 1
- select a from t1 having a=1;
- a
- 1
- drop table t1;
- create table t1 (a int);
- select variance(2) from t1;
- variance(2)
- NULL
- select stddev(2) from t1;
- stddev(2)
- NULL
- drop table t1;
- create table t1 (a int);
- insert into t1 values (1),(2);
- prepare stmt1 from 'SELECT COUNT(*) FROM t1';
- execute stmt1;
- COUNT(*)
- 2
- execute stmt1;
- COUNT(*)
- 2
- execute stmt1;
- COUNT(*)
- 2
- deallocate prepare stmt1;
- drop table t1;
- create table t1 (a int, primary key(a));
- insert into t1 values (1),(2);
- prepare stmt1 from 'SELECT max(a) FROM t1';
- execute stmt1;
- max(a)
- 2
- execute stmt1;
- max(a)
- 2
- execute stmt1;
- max(a)
- 2
- deallocate prepare stmt1;
- drop table t1;
- CREATE TABLE t1 (a int primary key);
- INSERT INTO t1 VALUES (1),(2),(3),(4);
- SELECT MAX(a) FROM t1 WHERE a > 5;
- MAX(a)
- NULL
- SELECT MIN(a) FROM t1 WHERE a < 0;
- MIN(a)
- NULL
- DROP TABLE t1;
- CREATE TABLE t1 (
- id int(10) unsigned NOT NULL auto_increment,
- val enum('one','two','three') NOT NULL default 'one',
- PRIMARY KEY (id)
- ) ENGINE=MyISAM DEFAULT CHARSET=utf8;
- INSERT INTO t1 VALUES
- (1,'one'),(2,'two'),(3,'three'),(4,'one'),(5,'two');
- select val, count(*) from t1 group by val;
- val count(*)
- one 2
- two 2
- three 1
- drop table t1;
- CREATE TABLE t1 (
- id int(10) unsigned NOT NULL auto_increment,
- val set('one','two','three') NOT NULL default 'one',
- PRIMARY KEY (id)
- ) ENGINE=MyISAM DEFAULT CHARSET=utf8;
- INSERT INTO t1 VALUES
- (1,'one'),(2,'two'),(3,'three'),(4,'one'),(5,'two');
- select val, count(*) from t1 group by val;
- val count(*)
- one 2
- two 2
- three 1
- drop table t1;
- create table t1(a int, b datetime);
- insert into t1 values (1, NOW()), (2, NOW());
- create table t2 select MAX(b) from t1 group by a;
- show create table t2;
- Table Create Table
- t2 CREATE TABLE `t2` (
- `MAX(b)` datetime default NULL
- ) ENGINE=MyISAM DEFAULT CHARSET=latin1
- drop table t1, t2;
- create table t1(f1 datetime);
- insert into t1 values (now());
- create table t2 select f2 from (select max(now()) f2 from t1) a;
- show columns from t2;
- Field Type Null Key Default Extra
- f2 datetime YES NULL
- drop table t2;
- create table t2 select f2 from (select now() f2 from t1) a;
- show columns from t2;
- Field Type Null Key Default Extra
- f2 datetime 0000-00-00 00:00:00
- drop table t2, t1;
- CREATE TABLE t1(
- id int PRIMARY KEY,
- a int,
- b int,
- INDEX i_b_id(a,b,id),
- INDEX i_id(a,id)
- );
- INSERT INTO t1 VALUES
- (1,1,4), (2,2,1), (3,1,3), (4,2,1), (5,1,1);
- SELECT MAX(id) FROM t1 WHERE id < 3 AND a=2 AND b=6;
- MAX(id)
- NULL
- DROP TABLE t1;
- CREATE TABLE t1(
- id int PRIMARY KEY,
- a int,
- b int,
- INDEX i_id(a,id),
- INDEX i_b_id(a,b,id)
- );
- INSERT INTO t1 VALUES
- (1,1,4), (2,2,1), (3,1,3), (4,2,1), (5,1,1);
- SELECT MAX(id) FROM t1 WHERE id < 3 AND a=2 AND b=6;
- MAX(id)
- NULL
- DROP TABLE t1;
- create table t1m (a int) engine=myisam;
- create table t1i (a int) engine=innodb;
- create table t2m (a int) engine=myisam;
- create table t2i (a int) engine=innodb;
- insert into t2m values (5);
- insert into t2i values (5);
- select min(a) from t1m;
- min(a)
- NULL
- select min(7) from t1m;
- min(7)
- NULL
- select min(7) from DUAL;
- min(7)
- NULL
- explain select min(7) from t2m join t1m;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select min(7) from t2m join t1m;
- min(7)
- NULL
- select max(a) from t1m;
- max(a)
- NULL
- select max(7) from t1m;
- max(7)
- NULL
- select max(7) from DUAL;
- max(7)
- NULL
- explain select max(7) from t2m join t1m;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
- select max(7) from t2m join t1m;
- max(7)
- NULL
- select 1, min(a) from t1m where a=99;
- 1 min(a)
- 1 NULL
- select 1, min(a) from t1m where 1=99;
- 1 min(a)
- 1 NULL
- select 1, min(1) from t1m where a=99;
- 1 min(1)
- select 1, min(1) from t1m where 1=99;
- 1 min(1)
- 1 NULL
- select 1, max(a) from t1m where a=99;
- 1 max(a)
- 1 NULL
- select 1, max(a) from t1m where 1=99;
- 1 max(a)
- 1 NULL
- select 1, max(1) from t1m where a=99;
- 1 max(1)
- select 1, max(1) from t1m where 1=99;
- 1 max(1)
- 1 NULL
- select min(a) from t1i;
- min(a)
- NULL
- select min(7) from t1i;
- min(7)
- NULL
- select min(7) from DUAL;
- min(7)
- NULL
- explain select min(7) from t2i join t1i;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t2i ALL NULL NULL NULL NULL 1
- 1 SIMPLE t1i ALL NULL NULL NULL NULL 1
- select min(7) from t2i join t1i;
- min(7)
- NULL
- select max(a) from t1i;
- max(a)
- NULL
- select max(7) from t1i;
- max(7)
- NULL
- select max(7) from DUAL;
- max(7)
- NULL
- explain select max(7) from t2i join t1i;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t2i ALL NULL NULL NULL NULL 1
- 1 SIMPLE t1i ALL NULL NULL NULL NULL 1
- select max(7) from t2i join t1i;
- max(7)
- NULL
- select 1, min(a) from t1i where a=99;
- 1 min(a)
- 1 NULL
- select 1, min(a) from t1i where 1=99;
- 1 min(a)
- 1 NULL
- select 1, min(1) from t1i where a=99;
- 1 min(1)
- 1 NULL
- select 1, min(1) from t1i where 1=99;
- 1 min(1)
- 1 NULL
- select 1, max(a) from t1i where a=99;
- 1 max(a)
- 1 NULL
- select 1, max(a) from t1i where 1=99;
- 1 max(a)
- 1 NULL
- select 1, max(1) from t1i where a=99;
- 1 max(1)
- 1 NULL
- select 1, max(1) from t1i where 1=99;
- 1 max(1)
- 1 NULL
- explain select count(*), min(7), max(7) from t1m, t1i;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1m system NULL NULL NULL NULL 0 const row not found
- 1 SIMPLE t1i ALL NULL NULL NULL NULL 1
- select count(*), min(7), max(7) from t1m, t1i;
- count(*) min(7) max(7)
- 0 NULL NULL
- explain select count(*), min(7), max(7) from t1m, t2i;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t1m system NULL NULL NULL NULL 0 const row not found
- 1 SIMPLE t2i ALL NULL NULL NULL NULL 1
- select count(*), min(7), max(7) from t1m, t2i;
- count(*) min(7) max(7)
- 0 NULL NULL
- explain select count(*), min(7), max(7) from t2m, t1i;
- id select_type table type possible_keys key key_len ref rows Extra
- 1 SIMPLE t2m system NULL NULL NULL NULL 1
- 1 SIMPLE t1i ALL NULL NULL NULL NULL 1
- select count(*), min(7), max(7) from t2m, t1i;
- count(*) min(7) max(7)
- 0 NULL NULL
- drop table t1m, t1i, t2m, t2i;