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drop table if exists t1,t2;
CREATE TABLE t1 (c int not null, d char (10) not null);
insert into t1 values(1,""),(2,"a"),(3,"b");
CREATE TEMPORARY TABLE t1 (a int not null, b char (10) not null);
insert into t1 values(4,"e"),(5,"f"),(6,"g");
alter table t1 rename t2;
select * from t1;
c d
1
2 a
3 b
select * from t2;
a b
4 e
5 f
6 g
CREATE TABLE t2 (x int not null, y int not null);
alter table t2 rename t1;
select * from t1;
a b
4 e
5 f
6 g
create TEMPORARY TABLE t2 engine=heap select * from t1;
create TEMPORARY TABLE IF NOT EXISTS t2 (a int) engine=heap;
Warnings:
Note 1050 Table 't2' already exists
CREATE TEMPORARY TABLE t1 (a int not null, b char (10) not null);
ERROR 42S01: Table 't1' already exists
ALTER TABLE t1 RENAME t2;
ERROR 42S01: Table 't2' already exists
select * from t2;
a b
4 e
5 f
6 g
alter table t2 add primary key (a,b);
drop table t1,t2;
select * from t1;
c d
1
2 a
3 b
drop table t2;
create temporary table t1 select *,2 as "e" from t1;
select * from t1;
c d e
1 2
2 a 2
3 b 2
drop table t1;
drop table t1;
CREATE TABLE t1 (pkCrash INTEGER PRIMARY KEY,strCrash VARCHAR(255));
INSERT INTO t1 ( pkCrash, strCrash ) VALUES ( 1, '1');
SELECT CONCAT_WS(pkCrash, strCrash) FROM t1;
CONCAT_WS(pkCrash, strCrash)
1
drop table t1;
create temporary table t1 select 1 as 'x';
drop table t1;
CREATE TABLE t1 (x INT);
INSERT INTO t1 VALUES (1), (2), (3);
CREATE TEMPORARY TABLE tmp SELECT *, NULL FROM t1;
drop table t1;
create temporary table t1 (id int(10) not null unique);
create temporary table t2 (id int(10) not null primary key,
val int(10) not null);
insert into t1 values (1),(2),(4);
insert into t2 values (1,1),(2,1),(3,1),(4,2);
select one.id, two.val, elt(two.val,'one','two') from t1 one, t2 two where two.id=one.id order by one.id;
id val elt(two.val,'one','two')
1 1 one
2 1 one
4 2 two
drop table t1,t2;
create temporary table t1 (a int not null);
insert into t1 values (1),(1);
alter table t1 add primary key (a);
ERROR 23000: Duplicate entry '1' for key 1
drop table t1;
CREATE TABLE t1 (
d datetime default NULL
) ENGINE=MyISAM;
INSERT INTO t1 VALUES ('2002-10-24 14:50:32'),('2002-10-24 14:50:33'),('2002-10-24 14:50:34'),('2002-10-24 14:50:34'),('2002-10-24 14:50:34'),('2002-10-24 14:50:35'),('2002-10-24 14:50:35'),('2002-10-24 14:50:35'),('2002-10-24 14:50:35'),('2002-10-24 14:50:36'),('2002-10-24 14:50:36'),('2002-10-24 14:50:36'),('2002-10-24 14:50:36'),('2002-10-24 14:50:37'),('2002-10-24 14:50:37'),('2002-10-24 14:50:37'),('2002-10-24 14:50:37'),('2002-10-24 14:50:38'),('2002-10-24 14:50:38'),('2002-10-24 14:50:38'),('2002-10-24 14:50:39'),('2002-10-24 14:50:39'),('2002-10-24 14:50:39'),('2002-10-24 14:50:39'),('2002-10-24 14:50:40'),('2002-10-24 14:50:40'),('2002-10-24 14:50:40');
flush status;
select * from t1 group by d;
d
2002-10-24 14:50:32
2002-10-24 14:50:33
2002-10-24 14:50:34
2002-10-24 14:50:35
2002-10-24 14:50:36
2002-10-24 14:50:37
2002-10-24 14:50:38
2002-10-24 14:50:39
2002-10-24 14:50:40
show status like "created_tmp%tables";
Variable_name Value
Created_tmp_disk_tables 0
Created_tmp_tables 1
drop table t1;
create table t1 (a int, b int, index(a), index(b));
create table t2 (c int auto_increment, d varchar(255), primary key (c));
insert into t1 values (3,1),(3,2);
insert into t2 values (NULL, 'foo'), (NULL, 'bar');
select d, c from t1 left join t2 on b = c where a = 3 order by d;
d c
bar 2
foo 1
drop table t1, t2;
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