drop table if exists t1; create table t1 (a int not null); insert into t1 values (1); insert into t1 values (a+2); insert into t1 values (a+3); insert into t1 values (4),(a+5); select * from t1; a 1 2 3 4 5 drop table t1; create table t1 (id int not null auto_increment primary key, username varchar(32) not null, unique (username)); insert into t1 values (0,"mysql"); insert into t1 values (0,"mysql ab"); insert into t1 values (0,"mysql a"); insert into t1 values (0,"r1manic"); insert into t1 values (0,"r1man"); drop table t1; create table t1 (a int not null auto_increment, primary key (a), t timestamp, c char(10) default "hello", i int); insert into t1 values (default,default,default,default), (default,default,default,default), (4,0,"a",5),(default,default,default,default); select a,t>0,c,i from t1; a t>0 c i 1 1 hello NULL 2 1 hello NULL 4 0 a 5 5 1 hello NULL truncate table t1; insert into t1 set a=default,t=default,c=default; insert into t1 set a=default,t=default,c=default,i=default; insert into t1 set a=4,t=0,c="a",i=5; insert into t1 set a=5,t=0,c="a",i=null; insert into t1 set a=default,t=default,c=default,i=default; select a,t>0,c,i from t1; a t>0 c i 1 1 hello NULL 2 1 hello NULL 4 0 a 5 5 0 a NULL 6 1 hello NULL drop table t1; create table t1 (sid char(20), id int(2) NOT NULL auto_increment, key(sid, id)); insert into t1 values ('skr',NULL),('skr',NULL),('test',NULL); select * from t1; sid id skr 1 skr 2 test 1 insert into t1 values ('rts',NULL),('rts',NULL),('test',NULL); select * from t1; sid id rts 1 rts 2 skr 1 skr 2 test 1 test 2 drop table t1; drop database if exists test_$1; create database test_$1; use test_$1; create table t1 (c int); insert into test_$1.t1 set test_$1.t1.c = '1'; drop database test_$1; use test; drop table if exists t1,t2,t3; create table t1(id1 int not null auto_increment primary key, t char(12)); create table t2(id2 int not null, t char(12)); create table t3(id3 int not null, t char(12), index(id3)); select count(*) from t2; count(*) 500 insert into t2 select t1.* from t1, t2 t, t3 where t1.id1 = t.id2 and t.id2 = t3.id3; select count(*) from t2; count(*) 25500 drop table if exists t1,t2,t3;