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  • 【收藏】常用SQL语句

    //MySQL 5.1参考手册
    
    CREATE TABLE pet (name VARCHAR(20), owner VARCHAR(20),
    species VARCHAR(20), sex CHAR(1), birth DATE, death DATE); //创建表
    
    
    mysql> show tables;  //查看数据库中的表
    +----------------+
    | Tables_in_test |
    +----------------+
    | pet            |
    +----------------+
    1 row in set (0.00 sec)
    
    
    mysql> describe pet;  //查看表的结构
    +---------+-------------+------+-----+---------+-------+
    | Field   | Type        | Null | Key | Default | Extra |
    +---------+-------------+------+-----+---------+-------+
    | name    | varchar(20) | YES  |     | NULL    |       |
    | owner   | varchar(20) | YES  |     | NULL    |       |
    | species | varchar(20) | YES  |     | NULL    |       |
    | sex     | char(1)     | YES  |     | NULL    |       |
    | birth   | date        | YES  |     | NULL    |       |
    | death   | date        | YES  |     | NULL    |       |
    +---------+-------------+------+-----+---------+-------+
    6 rows in set (0.00 sec)
    
    
    //导入txt文件中的数据
    LOAD DATA LOCAL INFILE 'E:\pet.txt' INTO TABLE pet;  //导入txt文件中的数据
    load data local infile 'E:\data.txt' into table pet; 
    
    mysql> INSERT INTO pet
        -> VALUES ('Puffball','Diane','hamster','f','1999-03-30',NULL);  //一次导入一条数据
    Query OK, 1 row affected (0.40 sec)
    
    
    mysql> select * from pet where name='bowser';   //查询name=XxxxX的数据
    +--------+-------+---------+------+------------+------------+
    | name   | owner | species | sex  | birth      | death      |
    +--------+-------+---------+------+------------+------------+
    | bowser | diane | dog     | m    | 1979-08-31 | 1995-07-29 |
    +--------+-------+---------+------+------------+------------+
    1 row in set (0.00 sec)
    
    
    mysql> select * from pet where birth>'1998-1-1';  //查询birth在1998-1-1之后的数据
    +----------+-------+---------+------+------------+-------+
    | name     | owner | species | sex  | birth      | death |
    +----------+-------+---------+------+------------+-------+
    | chirpy   | gwen  | bird    | f    | 1998-09-11 | NULL  |
    | Puffball | Diane | hamster | f    | 1999-03-30 | NULL  |
    +----------+-------+---------+------+------------+-------+
    2 rows in set (0.00 sec)
    
    
    
    mysql> select * from pet where species='dog' and sex='f';  //组合条件的使用
    +-------+--------+---------+------+------------+-------+
    | name  | owner  | species | sex  | birth      | death |
    +-------+--------+---------+------+------------+-------+
    | buffy | harold | dog     | f    | 1989-05-13 | NULL  |
    +-------+--------+---------+------+------------+-------+
    1 row in set (0.00 sec)
    
    
    mysql> select * from pet where species='dog' or species='bird';  //or操作符,满足一个条件即可
    +----------+--------+---------+------+------------+------------+
    | name     | owner  | species | sex  | birth      | death      |
    +----------+--------+---------+------+------------+------------+
    | buffy    | harold | dog     | f    | 1989-05-13 | NULL       |
    | fang     | benny  | dog     | m    | 1990-08-27 | NULL       |
    | bowser   | diane  | dog     | m    | 1979-08-31 | 1995-07-29 |
    | chirpy   | gwen   | bird    | f    | 1998-09-11 | NULL       |
    | whistler | gwen   | bird    |      | 1997-12-09 | NULL       |
    +----------+--------+---------+------+------------+------------+
    5 rows in set (0.00 sec)
    
    
    mysql> select * from pet where (species='cat' and sex='m')   //and、or混用
        -> or (species='dog' and sex='f');
    +-------+--------+---------+------+------------+-------+
    | name  | owner  | species | sex  | birth      | death |
    +-------+--------+---------+------+------------+-------+
    | claws | gwen   | cat     | m    | 1994-03-17 | NULL  |
    | buffy | harold | dog     | f    | 1989-05-13 | NULL  |
    +-------+--------+---------+------+------------+-------+
    2 rows in set (0.00 sec)
    
    
    mysql> select name,birth from pet;  //输出制定的字段内容
    +----------+------------+
    | name     | birth      |
    +----------+------------+
    | fluff    | 1993-02-04 |
    | claws    | 1994-03-17 |
    | buffy    | 1989-05-13 |
    | fang     | 1990-08-27 |
    | bowser   | 1979-08-31 |
    | chirpy   | 1998-09-11 |
    | whistler | 1997-12-09 |
    | slim     | 1996-04-29 |
    | Puffball | 1999-03-30 |
    +----------+------------+
    9 rows in set (0.00 sec)
    
    
    mysql> select distinct owner from pet;  //对输出的字段做去重处理
    +--------+
    | owner  |
    +--------+
    | harold |
    | gwen   |
    | benny  |
    | diane  |
    +--------+
    4 rows in set (0.00 sec)
    
    
    mysql> select name,birth from pet order by birth;  //对birth排序,默认升序
    +----------+------------+
    | name     | birth      |
    +----------+------------+
    | bowser   | 1979-08-31 |
    | buffy    | 1989-05-13 |
    | fang     | 1990-08-27 |
    | fluff    | 1993-02-04 |
    | claws    | 1994-03-17 |
    | slim     | 1996-04-29 |
    | whistler | 1997-12-09 |
    | chirpy   | 1998-09-11 |
    | Puffball | 1999-03-30 |
    +----------+------------+
    9 rows in set (0.00 sec)
    
    mysql> select name,birth from pet order by birth desc; //降序排列,最小值放第一个位置
    +----------+------------+
    | name     | birth      |
    +----------+------------+
    | Puffball | 1999-03-30 |
    | chirpy   | 1998-09-11 |
    | whistler | 1997-12-09 |
    | slim     | 1996-04-29 |
    | claws    | 1994-03-17 |
    | fluff    | 1993-02-04 |
    | fang     | 1990-08-27 |
    | buffy    | 1989-05-13 |
    | bowser   | 1979-08-31 |
    +----------+------------+
    9 rows in set (0.00 sec)
    
    
    mysql> select name,species,birth from pet order by species,birth desc; //对多列排序,一个升序一个降序
    +----------+---------+------------+
    | name     | species | birth      |
    +----------+---------+------------+
    | chirpy   | bird    | 1998-09-11 |
    | whistler | bird    | 1997-12-09 |
    | claws    | cat     | 1994-03-17 |
    | fluff    | cat     | 1993-02-04 |
    | fang     | dog     | 1990-08-27 |
    | buffy    | dog     | 1989-05-13 |
    | bowser   | dog     | 1979-08-31 |
    | Puffball | hamster | 1999-03-30 |
    | slim     | snake   | 1996-04-29 |
    +----------+---------+------------+
    9 rows in set (0.00 sec)
    
    
    //计算年龄
    mysql> select name,birth,curdate(),  //当前日期
        -> (year(curdate())-year(birth))-(right(curdate(),5)<right(birth,5))   //这里还是有一些不理解,后面慢慢研究
        -> as age  //字段重命名为age
        -> from pet;
    +----------+------------+------------+------+
    | name     | birth      | curdate()  | age  |
    +----------+------------+------------+------+
    | fluff    | 1993-02-04 | 2016-10-30 |   23 |
    | claws    | 1994-03-17 | 2016-10-30 |   22 |
    | buffy    | 1989-05-13 | 2016-10-30 |   27 |
    | fang     | 1990-08-27 | 2016-10-30 |   26 |
    | bowser   | 1979-08-31 | 2016-10-30 |   37 |
    | chirpy   | 1998-09-11 | 2016-10-30 |   18 |
    | whistler | 1997-12-09 | 2016-10-30 |   18 |
    | slim     | 1996-04-29 | 2016-10-30 |   20 |
    | Puffball | 1999-03-30 | 2016-10-30 |   17 |
    +----------+------------+------------+------+
    9 rows in set (0.00 sec)
    
    
    //针对rigth做的解释案例
    mysql> select curdate();  //当前日期,格式为2016-10-30
    +------------+
    | curdate()  |
    +------------+
    | 2016-10-30 |
    +------------+
    
    mysql> select right(curdate(),5);   //取后边5个字符,如此可以让年龄计算更加的精确
    +--------------------+
    | right(curdate(),5) |
    +--------------------+
    | 10-30              |
    +--------------------+
    
    
    mysql> select name,birth,curdate(),
        -> (year(curdate())-year(birth))-(right(curdate(),5)<right(birth,5))
        -> as age
        -> from pet
        -> order by age;   //按照年龄排序,age是字段的别称
    +----------+------------+------------+------+
    | name     | birth      | curdate()  | age  |
    +----------+------------+------------+------+
    | Puffball | 1999-03-30 | 2016-10-30 |   17 |
    | chirpy   | 1998-09-11 | 2016-10-30 |   18 |
    | whistler | 1997-12-09 | 2016-10-30 |   18 |
    | slim     | 1996-04-29 | 2016-10-30 |   20 |
    | claws    | 1994-03-17 | 2016-10-30 |   22 |
    | fluff    | 1993-02-04 | 2016-10-30 |   23 |
    | fang     | 1990-08-27 | 2016-10-30 |   26 |
    | buffy    | 1989-05-13 | 2016-10-30 |   27 |
    | bowser   | 1979-08-31 | 2016-10-30 |   37 |
    +----------+------------+------------+------+
    9 rows in set (0.00 sec)
    
    
    mysql> select name,birth,death,
        -> (year(death)-year(birth))-(right(death,5)< right(birth,5))  //计算已死亡年数
        -> as age
        -> from pet where death is not null order by age;    抓取不为空的数据
    +--------+------------+------------+------+
    | name   | birth      | death      | age  |
    +--------+------------+------------+------+
    | bowser | 1979-08-31 | 1995-07-29 |   15 |
    +--------+------------+------------+------+
    1 row in set (0.00 sec)
    
    
    mysql> select name,birth,month(birth) from pet;   /出生月份
    +----------+------------+--------------+
    | name     | birth      | month(birth) |
    +----------+------------+--------------+
    | fluff    | 1993-02-04 |            2 |
    | claws    | 1994-03-17 |            3 |
    | buffy    | 1989-05-13 |            5 |
    | fang     | 1990-08-27 |            8 |
    | bowser   | 1979-08-31 |            8 |
    | chirpy   | 1998-09-11 |            9 |
    | whistler | 1997-12-09 |           12 |
    | slim     | 1996-04-29 |            4 |
    | Puffball | 1999-03-30 |            3 |
    +----------+------------+--------------+
    9 rows in set (0.01 sec)
    
    
    mysql> select name,birth from pet
        -> where month(birth)=month(date_add(curdate(),interval 2 month));
        //在当前月份的基础上加2个月,得到月份是当前月份+2的数据
    +----------+------------+
    | name     | birth      |
    +----------+------------+
    | whistler | 1997-12-09 |
    +----------+------------+
    1 row in set (0.00 sec)
    
    “_”匹配任何单个字符,
    “%”匹配任意数目字符(包括零字符)
    
    
    mysql> select * from pet where name like 'b%';   //查找name以字母b开头的数据
    +--------+--------+---------+------+------------+------------+
    | name   | owner  | species | sex  | birth      | death      |
    +--------+--------+---------+------+------------+------------+
    | buffy  | harold | dog     | f    | 1989-05-13 | NULL       |
    | bowser | diane  | dog     | m    | 1979-08-31 | 1995-07-29 |
    +--------+--------+---------+------+------------+------------+
    2 rows in set (0.00 sec)
    
    
    mysql> select * from pet where name like '%fy';  //查找以fy结尾的数据
    +-------+--------+---------+------+------------+-------+
    | name  | owner  | species | sex  | birth      | death |
    +-------+--------+---------+------+------------+-------+
    | buffy | harold | dog     | f    | 1989-05-13 | NULL  |
    +-------+--------+---------+------+------------+-------+
    1 row in set (0.02 sec)
    
    
    mysql> select * from pet where name like '%w%';  //查找name中包含了w字母的数据
    +----------+-------+---------+------+------------+------------+
    | name     | owner | species | sex  | birth      | death      |
    +----------+-------+---------+------+------------+------------+
    | claws    | gwen  | cat     | m    | 1994-03-17 | NULL       |
    | bowser   | diane | dog     | m    | 1979-08-31 | 1995-07-29 |
    | whistler | gwen  | bird    |      | 1997-12-09 | NULL       |
    +----------+-------+---------+------+------------+------------+
    3 rows in set (0.00 sec)
    
    
    mysql> select * from pet where name like '_____';  //查找name正好包含5个字母的数据
    +-------+--------+---------+------+------------+-------+
    | name  | owner  | species | sex  | birth      | death |
    +-------+--------+---------+------+------------+-------+
    | fluff | harold | cat     | f    | 1993-02-04 | NULL  |
    | claws | gwen   | cat     | m    | 1994-03-17 | NULL  |
    | buffy | harold | dog     | f    | 1989-05-13 | NULL  |
    +-------+--------+---------+------+------------+-------+
    3 rows in set (0.00 sec)
    
    ‘.’匹配任何单个的字符。
    [...]:匹配在方括号内的任何字符。
    例如,“[abc]”匹配“a”、“b”或“c”。为了命名字符的范围,使用一个“-”。
    [a-z]:匹配任何字母
    [0-9]:匹配任何数字
    “ * ”匹配零个或多个在它前面的字符。
    例如,“x*”匹配任何数量的“x”字符,“[0-9]*”匹配任何数量的数字,而“.*”匹配任何数量的任何字符。
    “^”:开头
    “$”:结尾
    
    mysql> select * from pet where name regexp '^b';  //查找以模式字母b开始的数据
    +--------+--------+---------+------+------------+------------+
    | name   | owner  | species | sex  | birth      | death      |
    +--------+--------+---------+------+------------+------------+
    | buffy  | harold | dog     | f    | 1989-05-13 | NULL       |
    | bowser | diane  | dog     | m    | 1979-08-31 | 1995-07-29 |
    +--------+--------+---------+------+------------+------------+
    2 rows in set (0.00 sec)
    
    
    mysql> select * from pet where name regexp 'fy$';  //查找以模式字母fy结尾的数据
    +-------+--------+---------+------+------------+-------+
    | name  | owner  | species | sex  | birth      | death |
    +-------+--------+---------+------+------------+-------+
    | buffy | harold | dog     | f    | 1989-05-13 | NULL  |
    +-------+--------+---------+------+------------+-------+
    1 row in set (0.00 sec)
    
    
    mysql> select * from pet where name regexp 'w';  //正则查找包含字母w的数据
    +----------+-------+---------+------+------------+------------+
    | name     | owner | species | sex  | birth      | death      |
    +----------+-------+---------+------+------------+------------+
    | claws    | gwen  | cat     | m    | 1994-03-17 | NULL       |
    | bowser   | diane | dog     | m    | 1979-08-31 | 1995-07-29 |
    | whistler | gwen  | bird    |      | 1997-12-09 | NULL       |
    +----------+-------+---------+------+------------+------------+
    3 rows in set (0.00 sec)
    
    
    mysql> select * from pet where name regexp '^.{5}$';  //查找name正好包含5个字母的数据
    //正则的方式
    +-------+--------+---------+------+------------+-------+
    | name  | owner  | species | sex  | birth      | death |
    +-------+--------+---------+------+------------+-------+
    | fluff | harold | cat     | f    | 1993-02-04 | NULL  |
    | claws | gwen   | cat     | m    | 1994-03-17 | NULL  |
    | buffy | harold | dog     | f    | 1989-05-13 | NULL  |
    +-------+--------+---------+------+------------+-------+
    3 rows in set (0.00 sec)
    
    
    mysql> select count(*) from pet;   //计数行
    +----------+
    | count(*) |
    +----------+
    |        9 |
    +----------+
    1 row in set (0.00 sec)
    
    
    mysql> select owner,count(*) from pet group by owner;    //分组计数
    +--------+----------+
    | owner  | count(*) |
    +--------+----------+
    | benny  |        2 |
    | diane  |        2 |
    | gwen   |        3 |
    | harold |        2 |
    +--------+----------+
    4 rows in set (0.00 sec)
    
    
    mysql> select species,sex,count(*) from pet group by species,sex;  //按照species和sex2个条件进行分组
    +---------+------+----------+
    | species | sex  | count(*) |
    +---------+------+----------+
    | bird    |      |        1 |
    | bird    | f    |        1 |
    | cat     | f    |        1 |
    | cat     | m    |        1 |
    | dog     | f    |        1 |
    | dog     | m    |        2 |
    | hamster | f    |        1 |
    | snake   | m    |        1 |
    +---------+------+----------+
    8 rows in set (0.00 sec)
    
    
    mysql> create table event (name varchar(20),date date,  //创建event表,是pet的附表
        -> type varchar(15),remark varchar(255));
    Query OK, 0 rows affected (0.60 sec)
    
    
    //event.txt文件数据:
    fluffy    1995/5/15    litter    4 kittens, 3 female, 1 male
    buffy    1993/6/23    litter    5 puppies, 2 female, 3 male
    buffy    1994/6/19    litter    3 puppies, 3 female
    chirpy    1999/3/21    vet    needed beak straightened
    slim    1997/8/3    vet    broken rib
    bowser    1991/10/12    kennel
    fang    1991/10/12    kennel
    fang    1998/8/28    birthday    Gave him a new chew toy
    claws    1998/3/17    birthday    Gave him a new flea collar
    whistler    1998/12/9    birthday    First birthday
    
    
    mysql> LOAD DATA LOCAL INFILE 'E:\event.txt' INTO TABLE event;  //转载数据
    Query OK, 10 rows affected (0.20 sec)
    Records: 10  Deleted: 0  Skipped: 0  Warnings: 0
    
    
    //
    mysql> select pet.name,
        -> (year(date)-year(birth))-(right(date,5)<right(birth,5))  as age,
        -> remark
        -> from pet,event
        -> where pet.name=event.name and event.type='litter';
    +-------+------+------------------------------+
    | name  | age  | remark                       |
    +-------+------+------------------------------+
     |buffy |    4 | 5 puppies, 2 female, 3 male
             |   5 | 3 puppies, 3 female
    +-------+------+------------------------------+
    2 rows in set (0.00 sec)
    
    
    mysql> select pet.name,
        -> remark
        -> from pet,event
        -> where pet.name=event.name and event.type='litter';     //联合查找 type='litter'的数据
    +-------+------------------------------+
    | name  | remark                       |
    +-------+------------------------------+
     |buffy | 5 puppies, 2 female, 3 male
             |3 puppies, 3 female
    +-------+------------------------------+
    2 rows in set (0.00 sec)
    
    
    mysql> select database();   //查找当前所有数据库,这里特指正在使用的数据库
    +------------+
    | database() |
    +------------+
    | test       |
    +------------+
    1 row in set (0.00 sec)
    
    
    mysql> show tables;  //查看所有表
    +----------------+
    | Tables_in_test |
    +----------------+
    | event          |
    | pet            |
    +----------------+
    2 rows in set (0.00 sec)
    
    
    mysql>  describe pet;   //查找表的结构
    +---------+-------------+------+-----+---------+-------+
    | Field   | Type        | Null | Key | Default | Extra |
    +---------+-------------+------+-----+---------+-------+
    | name    | varchar(20) | YES  |     | NULL    |       |
    | owner   | varchar(20) | YES  |     | NULL    |       |
    | species | varchar(20) | YES  |     | NULL    |       |
    | sex     | char(1)     | YES  |     | NULL    |       |
    | birth   | date        | YES  |     | NULL    |       |
    | death   | date        | YES  |     | NULL    |       |
    +---------+-------------+------+-----+---------+-------+
    6 rows in set (0.00 sec)
    
    
    mysql> create table shop(            //创建shop数据库
        -> article int(4) unsigned zerofill default '0000' not null,    //指定数字位数,位数不足自动用0补齐
        -> dealer char(20) default '' not null,
        -> price double(16,2) default '0.00' not null,   //price保留2个小数点,16个字节,默认值0.00
        -> primary key(article,dealer));
    Query OK, 0 rows affected (0.62 sec)
    
    
    mysql> insert into  shop values    //插入数据,一种新的插入数据的形式
        -> (1,'a',3.45),
        -> (1,'b',3.99),
        -> (2,'a',10.99),
        -> (3,'b',1045),
        -> (3,'c',1.69),
        -> (3,'d',1.25),
        -> (4,'d',19.95);
    Query OK, 7 rows affected (0.40 sec)
    Records: 7  Duplicates: 0  Warnings: 0
    
    
    mysql> select * from shop;   //查看全部数据结果
    +---------+--------+---------+
    | article | dealer | price   |
    +---------+--------+---------+
    |    0001 | a      |    3.45 |
    |    0001 | b      |    3.99 |
    |    0002 | a      |   10.99 |
    |    0003 | b      | 1045.00 |
    |    0003 | c      |    1.69 |
    |    0003 | d      |    1.25 |
    |    0004 | d      |   19.95 |
    +---------+--------+---------+
    7 rows in set (0.00 sec)
    
    
    mysql> select max(article) as '物品号最大的商品' from shop;    //max
    +------------------+
    | 物品号最大的商品 |
    +------------------+
    |                4 |
    +------------------+
    1 row in set (0.02 sec)
    
    
    
    mysql> select article,dealer,price      //查找最贵商品的编号、销售商和价格等数据
        -> from shop
        -> where price=
        -> (select max(price) from shop);    //从子查询语句来实现
    +---------+--------+---------+
    | article | dealer | price   |
    +---------+--------+---------+
    |    0003 | b      | 1045.00 |
    +---------+--------+---------+
    1 row in set (0.00 sec)
    
    
    mysql> select article,dealer,price      //查找最贵商品的编号、销售商和价格等数据
        -> from shop                        //排序(降序)和limit方式综合实现
        -> order by price desc
        -> limit 1;
    +---------+--------+---------+
    | article | dealer | price   |
    +---------+--------+---------+
    |    0003 | b      | 1045.00 |
    +---------+--------+---------+
    1 row in set (0.00 sec)
    
    
    mysql> select article,max(price) as price      //分组求每种商品的最大值
        -> from shop
        -> group by article;
    +---------+---------+
    | article | price   |
    +---------+---------+
    |    0001 |    3.99 |
    |    0002 |   10.99 |
    |    0003 | 1045.00 |
    |    0004 |   19.95 |
    +---------+---------+
    4 rows in set (0.35 sec)
    
    
    mysql> select article,dealer,price   //定义要查找的字段
        -> from shop s1  //数据来源
        -> where price=  //定义数据需要满足的条件
        -> (select max(s2.price) from shop s2 where s1.article = s2.article);
    +---------+--------+---------+
    | article | dealer | price   |
    +---------+--------+---------+
    |    0001 | b      |    3.99 |
    |    0002 | a      |   10.99 |
    |    0003 | b      | 1045.00 |
    |    0004 | d      |   19.95 |
    +---------+--------+---------+
    4 rows in set (0.00 sec)
    
    
    //论坛用户访问时间数据
    mysql> create table t1 (year year(4),month int(2) unsigned zerofill,    //创建t1表
        -> day int(2) unsigned zerofill);
    Query OK, 0 rows affected (0.65 sec)
    
    mysql> insert into t1 values   //插入数据
        -> (2000,1,1),
        -> (2000,2,20),
        -> (2000,1,30),
        -> (2000,2,2),
        -> (2000,2,23),
        -> (2000,2,23);
    Query OK, 6 rows affected (0.40 sec)
    Records: 6  Duplicates: 0  Warnings: 0
    
    
    ysql> select year,month,bit_count(bit_or(1<<day)) as days   //查找同年同月访问量
        -> from t1
        -> group by year,month;
    +------+-------+------+
    | year | month | days |
    +------+-------+------+
    | 2000 |    01 |    2 |
    | 2000 |    02 |    3 |    //本来是4次,为什么是3次呢,做了去重处理
    +------+-------+------+
    2 rows in set (0.36 sec)
    
    
    
    mysql> create table animals(         //通过AUTO_INCREMENT属性为新的行产生唯一的标识
        -> id mediumint not null auto_increment,
        -> name char(20) not null,
        -> primary key(id)
        -> );
    Query OK, 0 rows affected (0.26 sec)
    
    mysql> insert into animals (name) values
        -> ('dog'),
        -> ('cat'),
        -> ('penguin'),
        -> ('lax'),
        -> ('whale'),
        -> ('ostrich');
    
    
    mysql> select * from animals;    //通过查看结果可以看出表对name自动加了编号
    +----+---------+
    | id | name    |
    +----+---------+
    |  1 | dog     |
    |  2 | cat     |
    |  3 | penguin |
    |  4 | lax     |
    |  5 | whale   |
    |  6 | ostrich |
    +----+---------+
    6 rows in set (0.00 sec)
    
    
    mysql> alter table animals auto_increment=100;   //定义数据的编号从100开始编号
    Query OK, 0 rows affected (0.37 sec)
    Records: 0  Duplicates: 0  Warnings: 0
    
    
    mysql> insert into animals (name) values   //插入一条新的数据
        -> ('cat1');
    Query OK, 1 row affected (0.40 sec)
    
    
    mysql> select * from animals;   //查看发现最新插入的数据编号为100,而不是编号7
    +-----+---------+
    | id  | name    |
    +-----+---------+
    |   1 | dog     |
    |   2 | cat     |
    |   3 | penguin |
    |   4 | lax     |
    |   5 | whale   |
    |   6 | ostrich |
    | 100 | cat1    |
    +-----+---------+
    7 rows in set (0.00 sec)
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  • 原文地址:https://www.cnblogs.com/dengyg200891/p/6022091.html
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