1.复制表结构和数据,但是不复制索引和外键:
create table a select * from b;
create table a like b;
insert into a select * from b;
rename table a.t to b.t;
--新建一个临时表
create table tmp as select * from youtable group by name ;
--删除原来的表
drop table youtable ;
--重命名表
alter table tmp rename youtable;
--新建一个临时表
create table tmp like youtable;
--取出不重复的数据
select * from youtable group by name;
--清空原来的表
truncate youtable;
--插入原来的表
insert into youtable select * from tmp;
--重命名表
drop table tmp;
SELECT FROM_UNIXTIME( 1249488000,'%Y-%m-%d %H:%i:%s') ;
SELECT DATE_FORMAT('1997-10-04 22:23:00', '%Y-%m-%d %H:%i:%s');
SELECT UNIX_TIMESTAMP('2009-08-06') ;
--查看日志
show binary logs;
show master logs;
--清除日志
PURGE MASTER LOGS TO 'mysql-bin.000035';
--手动删除10天前的mysql binlog日志
PURGE MASTER LOGS BEFORE DATE_SUB(CURRENT_DATE, INTERVAL 10 DAY);
select ROW_COUNT();
select FOUND_ROWS();
select LAST_INSERT_ID();
SET sql_mode='ANSI_QUOTES';
create table "a-b" (a int);
insert into node (name) select 'a' where no exists(select id from node where id=2 and name='a')
select replace(uuid(), '-', '');
GRANT ALL PRIVILEGES ON *.* TO username@"%" IDENTIFIED BY 'password' WITH GRANT OPTION;
LOAD DATA INFILE '/tmp/result100.txt' INTO TABLE analy_ip_file2 FIELDS TERMINATED BY ',' ENCLOSED BY '"' LINES TERMINATED BY ' ';
alter table userconfig add id int(4) auto_increment primary key;
show variables like '%max%';