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https://github.com/MariaDB/server.git
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147 lines
3.9 KiB
Text
147 lines
3.9 KiB
Text
create table t1 (USR_ID integer not null, MAX_REQ integer not null, constraint PK_SEA_USER primary key (USR_ID)) engine=InnoDB;
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insert into t1 values (1, 3);
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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;
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count(*) + MAX_REQ - MAX_REQ + MAX_REQ - MAX_REQ + MAX_REQ - MAX_REQ + MAX_REQ - MAX_REQ + MAX_REQ - MAX_REQ
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1
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select Case When Count(*) < MAX_REQ Then 1 Else 0 End from t1 where t1.USR_ID = 1 group by MAX_REQ;
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Case When Count(*) < MAX_REQ Then 1 Else 0 End
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1
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drop table t1;
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create table t1m (a int) engine=myisam;
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create table t1i (a int) engine=innodb;
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create table t2m (a int) engine=myisam;
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create table t2i (a int) engine=innodb;
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insert into t2m values (5);
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insert into t2i values (5);
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select min(a) from t1m;
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min(a)
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NULL
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select min(7) from t1m;
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min(7)
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NULL
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select min(7) from DUAL;
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min(7)
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7
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explain select min(7) from t2m join t1m;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
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select min(7) from t2m join t1m;
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min(7)
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NULL
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select max(a) from t1m;
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max(a)
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NULL
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select max(7) from t1m;
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max(7)
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NULL
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select max(7) from DUAL;
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max(7)
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7
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explain select max(7) from t2m join t1m;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
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select max(7) from t2m join t1m;
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max(7)
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NULL
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select 1, min(a) from t1m where a=99;
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1 min(a)
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1 NULL
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select 1, min(a) from t1m where 1=99;
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1 min(a)
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1 NULL
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select 1, min(1) from t1m where a=99;
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1 min(1)
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1 NULL
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select 1, min(1) from t1m where 1=99;
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1 min(1)
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1 NULL
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select 1, max(a) from t1m where a=99;
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1 max(a)
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1 NULL
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select 1, max(a) from t1m where 1=99;
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1 max(a)
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1 NULL
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select 1, max(1) from t1m where a=99;
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1 max(1)
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1 NULL
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select 1, max(1) from t1m where 1=99;
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1 max(1)
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1 NULL
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select min(a) from t1i;
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min(a)
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NULL
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select min(7) from t1i;
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min(7)
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NULL
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select min(7) from DUAL;
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min(7)
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7
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explain select min(7) from t2i join t1i;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t2i ALL NULL NULL NULL NULL 1
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1 SIMPLE t1i ALL NULL NULL NULL NULL 1 Using join buffer (flat, BNL join)
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select min(7) from t2i join t1i;
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min(7)
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NULL
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select max(a) from t1i;
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max(a)
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NULL
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select max(7) from t1i;
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max(7)
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NULL
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select max(7) from DUAL;
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max(7)
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7
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explain select max(7) from t2i join t1i;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t2i ALL NULL NULL NULL NULL 1
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1 SIMPLE t1i ALL NULL NULL NULL NULL 1 Using join buffer (flat, BNL join)
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select max(7) from t2i join t1i;
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max(7)
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NULL
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select 1, min(a) from t1i where a=99;
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1 min(a)
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1 NULL
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select 1, min(a) from t1i where 1=99;
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1 min(a)
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1 NULL
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select 1, min(1) from t1i where a=99;
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1 min(1)
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1 NULL
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select 1, min(1) from t1i where 1=99;
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1 min(1)
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1 NULL
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select 1, max(a) from t1i where a=99;
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1 max(a)
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1 NULL
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select 1, max(a) from t1i where 1=99;
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1 max(a)
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1 NULL
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select 1, max(1) from t1i where a=99;
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1 max(1)
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1 NULL
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select 1, max(1) from t1i where 1=99;
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1 max(1)
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1 NULL
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explain select count(*), min(7), max(7) from t1m, t1i;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1m system NULL NULL NULL NULL 0 const row not found
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1 SIMPLE t1i ALL NULL NULL NULL NULL 1
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select count(*), min(7), max(7) from t1m, t1i;
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count(*) min(7) max(7)
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0 NULL NULL
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explain select count(*), min(7), max(7) from t1m, t2i;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1m system NULL NULL NULL NULL 0 const row not found
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1 SIMPLE t2i ALL NULL NULL NULL NULL 1
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select count(*), min(7), max(7) from t1m, t2i;
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count(*) min(7) max(7)
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0 NULL NULL
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explain select count(*), min(7), max(7) from t2m, t1i;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t2m system NULL NULL NULL NULL 1
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1 SIMPLE t1i ALL NULL NULL NULL NULL 1
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select count(*), min(7), max(7) from t2m, t1i;
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count(*) min(7) max(7)
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0 NULL NULL
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drop table t1m, t1i, t2m, t2i;
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