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MySQL知识点整理

时间：2021-07-01 10:21:17 帮助过：14人阅读

# 制作MySQL的Windows服务，在终端执行此命令： 2 "c:\mysql-5.7.16-winx64\bin\mysqld" --install 3 4 # 移除MySQL的Windows服务，在终端执行此命令： 5 "c:\mysql-5.7.16-winx64\bin\mysqld" --remove

注册成服务之后，以后再启动和关闭MySQL服务时，仅需执行如下命令：

  1. <span style="color: #008080">1</span> <span style="color: #000000"># 启动MySQL服务
  2. </span><span style="color: #008080">2</span> <span style="color: #000000">net start mysql
  3. </span><span style="color: #008080">3</span>  
  4. <span style="color: #008080">4</span> <span style="color: #000000"># 关闭MySQL服务
  5. </span><span style="color: #008080">5</span> net stop mysql

二、数据库操作

1.基本操作

  1. <span style="color: #008080"> 1</span> <span style="color: #000000">show databases;#显示数据库
  2. </span><span style="color: #008080"> 2</span> 
  3. <span style="color: #008080"> 3</span> <span style="color: #000000">use 数据库名称；#进入当前数据库目录下
  4. </span><span style="color: #008080"> 4</span> 
  5. <span style="color: #008080"> 5</span> <span style="color: #000000">show tables；#显示当前使用的数据库中所有表
  6. </span><span style="color: #008080"> 6</span> <span style="color: #0000ff">select</span> * <span style="color: #0000ff">from</span><span style="color: #000000"> 表名;#读取文件内容
  7. </span><span style="color: #008080"> 7</span> 
  8. <span style="color: #008080"> 8</span> <span style="color: #0000ff">select</span> name,age,id <span style="color: #0000ff">from</span><span style="color: #000000"> 表名;#按name，age，id顺序读取文件内容
  9. </span><span style="color: #008080"> 9</span> 
  10. <span style="color: #008080">10</span> <span style="color: #000000">use mysql;#回到数据库起始目录
  11. </span><span style="color: #008080">11</span> 
  12. <span style="color: #008080">12</span> <span style="color: #0000ff">select</span> user,host <span style="color: #0000ff">from</span> user;#显示数据库用户信息

 

2.用户管理

  1. <span style="color: #008080">1</span> <span style="color: #000000">创建用户
  2. </span><span style="color: #008080">2</span>     create user <span style="color: #800000">‘</span><span style="color: #800000">用户名</span><span style="color: #800000">‘</span>@<span style="color: #800000">‘</span><span style="color: #800000">IP地址</span><span style="color: #800000">‘</span> identified by <span style="color: #800000">‘</span><span style="color: #800000">密码</span><span style="color: #800000">‘</span><span style="color: #000000">;
  3. </span><span style="color: #008080">3</span> <span style="color: #000000">删除用户
  4. </span><span style="color: #008080">4</span>     drop user <span style="color: #800000">‘</span><span style="color: #800000">用户名</span><span style="color: #800000">‘</span>@<span style="color: #800000">‘</span><span style="color: #800000">IP地址</span><span style="color: #800000">‘</span><span style="color: #000000">;
  5. </span><span style="color: #008080">5</span> <span style="color: #000000">修改用户
  6. </span><span style="color: #008080">6</span>     rename user <span style="color: #800000">‘</span><span style="color: #800000">用户名</span><span style="color: #800000">‘</span>@<span style="color: #800000">‘</span><span style="color: #800000">IP地址</span><span style="color: #800000">‘</span>; to <span style="color: #800000">‘</span><span style="color: #800000">新用户名</span><span style="color: #800000">‘</span>@<span style="color: #800000">‘</span><span style="color: #800000">IP地址</span><span style="color: #800000">‘</span><span style="color: #000000">;;
  7. </span><span style="color: #008080">7</span> <span style="color: #000000">修改密码
  8. </span><span style="color: #008080">8</span>     <span style="color: #0000ff">set</span> password <span style="color: #0000ff">for</span> <span style="color: #800000">‘</span><span style="color: #800000">用户名</span><span style="color: #800000">‘</span>@<span style="color: #800000">‘</span><span style="color: #800000">IP地址</span><span style="color: #800000">‘</span> = Password(<span style="color: #800000">‘</span><span style="color: #800000">新密码</span><span style="color: #800000">‘</span>)
技术分享 
  1. <span style="color: #000000"> 用户名@IP地址         用户只能在改IP下才能访问
  2.             用户名@</span><span style="color: #800080">192.168</span>.<span style="color: #800080">1</span>.%   用户只能在改IP段下才能访问(通配符%<span style="color: #000000">表示任意)
  3.             用户名@</span>%             用户可以再任意IP下访问(默认IP地址为%<span style="color: #000000">)
  4. 示例：
  5. grant all privileges on db1.tb1 TO </span><span style="color: #800000">‘</span><span style="color: #800000">用户名</span><span style="color: #800000">‘</span>@<span style="color: #800000">‘</span><span style="color: #800000">IP</span><span style="color: #800000">‘</span><span style="color: #000000">
  6.             grant </span><span style="color: #0000ff">select</span> on db1.* TO <span style="color: #800000">‘</span><span style="color: #800000">用户名</span><span style="color: #800000">‘</span>@<span style="color: #800000">‘</span><span style="color: #800000">IP</span><span style="color: #800000">‘</span><span style="color: #000000">
  7.             grant </span><span style="color: #0000ff">select</span>,insert on *.* TO <span style="color: #800000">‘</span><span style="color: #800000">用户名</span><span style="color: #800000">‘</span>@<span style="color: #800000">‘</span><span style="color: #800000">IP</span><span style="color: #800000">‘</span><span style="color: #000000">
  8.             revoke </span><span style="color: #0000ff">select</span> on db1.tb1 <span style="color: #0000ff">from</span> <span style="color: #800000">‘</span><span style="color: #800000">用户名</span><span style="color: #800000">‘</span>@<span style="color: #800000">‘</span><span style="color: #800000">IP</span><span style="color: #800000">‘</span>
注意事项和实例

 

3.授权管理

  1. <span style="color: #008080">1</span> show grants <span style="color: #0000ff">for</span> <span style="color: #800000">‘</span><span style="color: #800000">用户</span><span style="color: #800000">‘</span>@<span style="color: #800000">‘</span><span style="color: #800000">IP地址</span><span style="color: #800000">‘</span>                  --<span style="color: #000000"> 查看权限
  2. </span><span style="color: #008080">2</span> grant  权限 on 数据库.表 to   <span style="color: #800000">‘</span><span style="color: #800000">用户</span><span style="color: #800000">‘</span>@<span style="color: #800000">‘</span><span style="color: #800000">IP地址</span><span style="color: #800000">‘</span>      --<span style="color: #000000"> 授权
  3. </span><span style="color: #008080">3</span> revoke 权限 on 数据库.表 <span style="color: #0000ff">from</span> <span style="color: #800000">‘</span><span style="color: #800000">用户</span><span style="color: #800000">‘</span>@<span style="color: #800000">‘</span><span style="color: #800000">IP地址</span><span style="color: #800000">‘</span>      -- 取消权限
技术分享 
  1. <span style="color: #000000">all privileges  除grant外的所有权限
  2.             </span><span style="color: #0000ff">select</span><span style="color: #000000">          仅查权限
  3.             </span><span style="color: #0000ff">select</span><span style="color: #000000">,insert   查和插入权限
  4.             ...
  5.             usage                   无访问权限
  6.             alter                   使用alter table
  7.             alter routine           使用alter procedure和drop procedure
  8.             create                  使用create table
  9.             create routine          使用create procedure
  10.             create temporary tables 使用create temporary tables
  11.             create user             使用create user、drop user、rename user和revoke  all privileges
  12.             create view             使用create view
  13.             delete                  使用delete
  14.             drop                    使用drop table
  15.             execute                 使用call和存储过程
  16.             file                    使用select into outfile 和 load data infile
  17.             grant option            使用grant 和 revoke
  18.             index                   使用index
  19.             insert                  使用insert
  20.             </span><span style="color: #0000ff">lock</span><span style="color: #000000"> tables             使用lock table
  21.             process                 使用show full processlist
  22.             </span><span style="color: #0000ff">select</span><span style="color: #000000">                  使用select
  23.             show databases          使用show databases
  24.             show view               使用show view
  25.             update                  使用update
  26.             reload                  使用flush
  27.             shutdown                使用mysqladmin shutdown(关闭MySQL)
  28.             super                   ????使用change master、kill、logs、purge、master和set </span><span style="color: #0000ff">global</span><span style="color: #000000">。还允许mysqladmin????????调试登陆
  29.             replication client      服务器位置的访问
  30.             replication slave       由复制从属使用
  31. 对于权限</span>
权限内容 技术分享 
  1. <span style="color: #000000"> 对于目标数据库以及内部其他：
  2.             数据库名.</span>*<span style="color: #000000">           数据库中的所有
  3.             数据库名.表          指定数据库中的某张表
  4.             数据库名.存储过程     指定数据库中的存储过程
  5.             </span>*.*                所有数据库
其他

 

三、数据表操作

1.创建文件夹

  1. <span style="color: #008080">1</span> <span style="color: #000000">create database db2;#创建
  2. </span><span style="color: #008080">2</span> create database db2 <span style="color: #0000ff">default</span><span style="color: #000000"> charset utf8;#涉及编码问题，需要添加编码方式
  3. </span><span style="color: #008080">3</span> 
  4. <span style="color: #008080">4</span> drop database db2;#删除

 

2.创建表

  1. <span style="color: #008080">1</span> <span style="color: #000000">create table t1(
  2. </span><span style="color: #008080">2</span>             列名 类型 <span style="color: #0000ff">null</span><span style="color: #000000">,
  3. </span><span style="color: #008080">3</span>             列名 类型 not <span style="color: #0000ff">null</span><span style="color: #000000">,
  4. </span><span style="color: #008080">4</span>             列名 类型 not <span style="color: #0000ff">null</span><span style="color: #000000"> auto_increment primary key,
  5. </span><span style="color: #008080">5</span>             id <span style="color: #0000ff">int</span><span style="color: #000000">,
  6. </span><span style="color: #008080">6</span>             name <span style="color: #0000ff">char</span>(<span style="color: #800080">10</span><span style="color: #000000">)
  7. </span><span style="color: #008080">7</span>         )engine=innodb <span style="color: #0000ff">default</span> charset=utf8;
技术分享 
  1. <span style="color: #000000">是否可空，null表示空，非字符串
  2.             not </span><span style="color: #0000ff">null</span>    -<span style="color: #000000"> 不可空
  3.             </span><span style="color: #0000ff">null</span>        - 可空
null 技术分享 
  1. <span style="color: #000000">      默认值，创建列时可以指定默认值，当插入数据时如果未主动设置，则自动添加默认值
  2.             create table tb1(
  3.                 nid </span><span style="color: #0000ff">int</span> not <span style="color: #0000ff">null</span> defalut <span style="color: #800080">2</span><span style="color: #000000">,
  4.                 num </span><span style="color: #0000ff">int</span> not <span style="color: #0000ff">null</span><span style="color: #000000">
  5.             )</span>
默认值 技术分享 
  1. <span style="color: #000000">自增，如果为某列设置自增列，插入数据时无需设置此列，默认将自增（表中只能有一个自增列）
  2.             create table tb1(
  3.                 nid </span><span style="color: #0000ff">int</span> not <span style="color: #0000ff">null</span><span style="color: #000000"> auto_increment primary key,
  4.                 num </span><span style="color: #0000ff">int</span> <span style="color: #0000ff">null</span><span style="color: #000000">
  5.             )
  6.             或
  7.             create table tb1(
  8.                 nid </span><span style="color: #0000ff">int</span> not <span style="color: #0000ff">null</span><span style="color: #000000"> auto_increment,
  9.                 num </span><span style="color: #0000ff">int</span> <span style="color: #0000ff">null</span><span style="color: #000000">,
  10.                 index(nid)
  11.             )
  12.             注意：</span><span style="color: #800080">1</span><span style="color: #000000">、对于自增列，必须是索引（含主键）。
  13.                  </span><span style="color: #800080">2</span><span style="color: #000000">、对于自增可以设置步长和起始值
  14.                      show session variables like </span><span style="color: #800000">‘</span><span style="color: #800000">auto_inc%</span><span style="color: #800000">‘</span><span style="color: #000000">;
  15.                      </span><span style="color: #0000ff">set</span> session auto_increment_increment=<span style="color: #800080">2</span><span style="color: #000000">;
  16.                      </span><span style="color: #0000ff">set</span> session auto_increment_offset=<span style="color: #800080">10</span><span style="color: #000000">;
  17.                      shwo </span><span style="color: #0000ff">global</span>  variables like <span style="color: #800000">‘</span><span style="color: #800000">auto_inc%</span><span style="color: #800000">‘</span><span style="color: #000000">;
  18.                      </span><span style="color: #0000ff">set</span> <span style="color: #0000ff">global</span> auto_increment_increment=<span style="color: #800080">2</span><span style="color: #000000">;
  19.                      </span><span style="color: #0000ff">set</span> <span style="color: #0000ff">global</span> auto_increment_offset=<span style="color: #800080">10</span><span style="color: #000000">;
  20. 自增</span>
auto_increment ：自增 技术分享 
  1. <span style="color: #000000">主键，一种特殊的唯一索引，不允许有空值，如果主键使用单个列，则它的值必须唯一，如果是多列，则其组合必须唯一。
  2.             create table tb1(
  3.                 nid </span><span style="color: #0000ff">int</span> not <span style="color: #0000ff">null</span><span style="color: #000000"> auto_increment primary key,
  4.                 num </span><span style="color: #0000ff">int</span> <span style="color: #0000ff">null</span><span style="color: #000000">
  5.             )
  6.             或
  7.             create table tb1(
  8.                 nid </span><span style="color: #0000ff">int</span> not <span style="color: #0000ff">null</span><span style="color: #000000">,
  9.                 num </span><span style="color: #0000ff">int</span> not <span style="color: #0000ff">null</span><span style="color: #000000">,
  10.                 primary key(nid,num)
  11.             )
  12. 主键</span>
primary key：主键 表示 约束(不能重复且不能为空); 加速查找 技术分享 
  1. <span style="color: #000000">外键，一个特殊的索引，只能是指定内容
  2.             creat table color(
  3.                 nid </span><span style="color: #0000ff">int</span> not <span style="color: #0000ff">null</span><span style="color: #000000"> primary key,
  4.                 name </span><span style="color: #0000ff">char</span>(<span style="color: #800080">16</span>) not <span style="color: #0000ff">null</span><span style="color: #000000">
  5.             )
  6.             create table fruit(
  7.                 nid </span><span style="color: #0000ff">int</span> not <span style="color: #0000ff">null</span><span style="color: #000000"> primary key,
  8.                 smt </span><span style="color: #0000ff">char</span>(<span style="color: #800080">32</span>) <span style="color: #0000ff">null</span><span style="color: #000000"> ,
  9.                 color_id </span><span style="color: #0000ff">int</span> not <span style="color: #0000ff">null</span><span style="color: #000000">,
  10.                 constraint fk_cc foreign key (color_id) references color(nid)
  11.             )
  12. </span><span style="color: #800000">‘‘‘
  13. </span><span style="color: #000000">create table userinfo(
  14.             uid bigint auto_increment primary key,
  15.             name varchar(</span><span style="color: #800080">32</span><span style="color: #000000">),
  16.             department_id </span><span style="color: #0000ff">int</span><span style="color: #000000">,
  17.             xx_id </span><span style="color: #0000ff">int</span><span style="color: #000000">,
  18.             constraint fk_user_depar foreign key (</span><span style="color: #800000">"</span><span style="color: #800000">department_id</span><span style="color: #800000">"</span>,) references department(<span style="color: #800000">‘</span><span style="color: #800000">id</span><span style="color: #800000">‘</span><span style="color: #000000">),
  19.             constraint fk_xx_ff foreign key (</span><span style="color: #800000">"</span><span style="color: #800000">xx_id</span><span style="color: #800000">"</span>,) references XX(<span style="color: #800000">‘</span><span style="color: #800000">id</span><span style="color: #800000">‘</span><span style="color: #000000">)
  20.         )engine</span>=innodb <span style="color: #0000ff">default</span> charset=<span style="color: #000000">utf8;
  21.         
  22.         create table department(
  23.             id bigint auto_increment primary key,
  24.             title </span><span style="color: #0000ff">char</span>(<span style="color: #800080">15</span><span style="color: #000000">)
  25.         )engine</span>=innodb <span style="color: #0000ff">default</span> charset=<span style="color: #000000">utf8;
  26.         
  27. </span><span style="color: #800000">‘‘‘</span>
外键

2.删除表

  1. <span style="color: #008080">1</span> drop table 表名

3.清空表

  1. <span style="color: #008080">1</span> delete <span style="color: #0000ff">from</span><span style="color: #000000"> 表名
  2. </span><span style="color: #008080">2</span> truncate table 表名

4.修改表中内容

  1. <span style="color: #008080">1</span> <span style="color: #000000">插入数据：
  2. </span><span style="color: #008080">2</span>     insert into t1(id,name) values(<span style="color: #800080">1</span>,<span style="color: #800000">‘</span><span style="color: #800000">alex</span><span style="color: #800000">‘</span><span style="color: #000000">);
  3. </span><span style="color: #008080">3</span> <span style="color: #000000">删除：
  4. </span><span style="color: #008080">4</span>     delete <span style="color: #0000ff">from</span> t1 <span style="color: #0000ff">where</span> id<<span style="color: #800080">6</span>
  5. <span style="color: #008080">5</span> <span style="color: #000000">修改：
  6. </span><span style="color: #008080">6</span>     update t1 <span style="color: #0000ff">set</span> age=<span style="color: #800080">18</span><span style="color: #000000">;
  7. </span><span style="color: #008080">7</span>     update t1 <span style="color: #0000ff">set</span> age=<span style="color: #800080">18</span> <span style="color: #0000ff">where</span> age=<span style="color: #800080">17</span><span style="color: #000000">;
  8. </span><span style="color: #008080">8</span> <span style="color: #000000">查看数据：
  9. </span><span style="color: #008080">9</span>     <span style="color: #0000ff">select</span> * <span style="color: #0000ff">from</span> t1;

 

5.基本数据类型

技术分享 
  1. <span style="color: #000000">bit[(M)]
  2.             二进制位（</span><span style="color: #800080">101001</span>），m表示二进制位的长度（<span style="color: #800080">1</span>-<span style="color: #800080">64</span>），默认m＝<span style="color: #800080">1</span><span style="color: #000000">
  3.         tinyint[(m)] [unsigned] [zerofill]
  4.             小整数，数据类型用于保存一些范围的整数数值范围：
  5.             有符号：
  6.                 </span>-<span style="color: #800080">128</span> ～ <span style="color: #800080">127</span><span style="color: #000000">.
  7.             无符号：
  8. ～ </span><span style="color: #800080">255</span><span style="color: #000000">
  9.             特别的： MySQL中无布尔值，使用tinyint(</span><span style="color: #800080">1</span><span style="color: #000000">)构造。
  10.         </span><span style="color: #0000ff">int</span><span style="color: #000000">[(m)][unsigned][zerofill]
  11.             整数，数据类型用于保存一些范围的整数数值范围：
  12.                 有符号：
  13.                     </span>-<span style="color: #800080">2147483648</span> ～ <span style="color: #800080">2147483647</span><span style="color: #000000">
  14.                 无符号：
  15. ～ </span><span style="color: #800080">4294967295</span><span style="color: #000000">
  16.             特别的：整数类型中的m仅用于显示，对存储范围无限制。例如： </span><span style="color: #0000ff">int</span>(<span style="color: #800080">5</span>),当插入数据2时，<span style="color: #0000ff">select</span> 时数据显示为： <span style="color: #800080">00002</span><span style="color: #000000">
  17.         bigint[(m)][unsigned][zerofill]
  18.             大整数，数据类型用于保存一些范围的整数数值范围：
  19.                 有符号：
  20.                     </span>-<span style="color: #800080">9223372036854775808</span> ～ <span style="color: #800080">9223372036854775807</span><span style="color: #000000">
  21.                 无符号：
  22.  ～  </span><span style="color: #800080">18446744073709551615</span>
  23.         <span style="color: #0000ff">decimal</span><span style="color: #000000">[(m[,d])] [unsigned] [zerofill]
  24.             准确的小数值，m是数字总个数（负号不算），d是小数点后个数。 m最大值为65，d最大值为30。
  25.             特别的：对于精确数值计算时需要用此类型
  26.                    decaimal能够存储精确值的原因在于其内部按照字符串存储。
  27.         FLOAT[(M,D)] [UNSIGNED] [ZEROFILL]
  28.             单精度浮点数（非准确小数值），m是数字总个数，d是小数点后个数。
  29.                 无符号：
  30.                     </span>-<span style="color: #800080">3.402823466E+38</span> to -<span style="color: #800080">1.175494351E-38</span><span style="color: #000000">,
  31.                     </span><span style="color: #800080">1.175494351E-38</span> to <span style="color: #800080">3.402823466E+38</span><span style="color: #000000">
  32.                 有符号：
  33.                     </span><span style="color: #800080">1.175494351E-38</span> to <span style="color: #800080">3.402823466E+38</span>
  34.             **** 数值越大，越不准确 ****<span style="color: #000000">
  35.         DOUBLE[(M,D)] [UNSIGNED] [ZEROFILL]
  36.             双精度浮点数（非准确小数值），m是数字总个数，d是小数点后个数。
  37.                 无符号：
  38.                     </span>-<span style="color: #800080">1.7976931348623157E+308</span> to -<span style="color: #800080">2.2250738585072014E-308</span>
  39.                     <span style="color: #800080">2.2250738585072014E-308</span> to <span style="color: #800080">1.7976931348623157E+308</span><span style="color: #000000">
  40.                 有符号：
  41.                     </span><span style="color: #800080">2.2250738585072014E-308</span> to <span style="color: #800080">1.7976931348623157E+308</span>
  42.             **** 数值越大，越不准确 ****
  43.         <span style="color: #0000ff">char</span><span style="color: #000000"> (m)
  44.             char数据类型用于表示固定长度的字符串，可以包含最多达255个字符。其中m代表字符串的长度。
  45.             PS: 即使数据小于m长度，也会占用m长度
  46.         varchar(m)
  47.             varchars数据类型用于变长的字符串，可以包含最多达255个字符。其中m代表该数据类型所允许保存的字符串的最大长度，只要长度小于该最大值的字符串都可以被保存在该数据类型中。
  48.             注：虽然varchar使用起来较为灵活，但是从整个系统的性能角度来说，char数据类型的处理速度更快，有时甚至可以超出varchar处理速度的50</span>%<span style="color: #000000">。因此，用户在设计数据库时应当综合考虑各方面的因素，以求达到最佳的平衡
  49.         text
  50.             text数据类型用于保存变长的大字符串，可以组多到65535 (</span><span style="color: #800080">2</span>**<span style="color: #800080">16</span> ? <span style="color: #800080">1</span><span style="color: #000000">)个字符。
  51.         mediumtext
  52.             A TEXT column with a maximum length of </span><span style="color: #800080">16</span>,<span style="color: #800080">777</span>,<span style="color: #800080">215</span> (<span style="color: #800080">2</span>**<span style="color: #800080">24</span> ? <span style="color: #800080">1</span><span style="color: #000000">) characters.
  53.         longtext
  54.             A TEXT column with a maximum length of </span><span style="color: #800080">4</span>,<span style="color: #800080">294</span>,<span style="color: #800080">967</span>,<span style="color: #800080">295</span> or 4GB (<span style="color: #800080">2</span>**<span style="color: #800080">32</span> ? <span style="color: #800080">1</span><span style="color: #000000">) characters.
  55.         </span><span style="color: #0000ff">enum</span><span style="color: #000000">
  56.             枚举类型，
  57.             An ENUM column can have a maximum of </span><span style="color: #800080">65</span>,<span style="color: #800080">535</span> distinct elements. (The practical limit <span style="color: #0000ff">is</span> less than <span style="color: #800080">3000</span><span style="color: #000000">.)
  58.             示例：
  59.                 CREATE TABLE shirts (
  60.                     name VARCHAR(</span><span style="color: #800080">40</span><span style="color: #000000">),
  61.                     size ENUM(</span><span style="color: #800000">‘</span><span style="color: #800000">x-small</span><span style="color: #800000">‘</span>, <span style="color: #800000">‘</span><span style="color: #800000">small</span><span style="color: #800000">‘</span>, <span style="color: #800000">‘</span><span style="color: #800000">medium</span><span style="color: #800000">‘</span>, <span style="color: #800000">‘</span><span style="color: #800000">large</span><span style="color: #800000">‘</span>, <span style="color: #800000">‘</span><span style="color: #800000">x-large</span><span style="color: #800000">‘</span><span style="color: #000000">)
  62.                 );
  63.                 INSERT INTO shirts (name, size) VALUES (</span><span style="color: #800000">‘</span><span style="color: #800000">dress shirt</span><span style="color: #800000">‘</span>,<span style="color: #800000">‘</span><span style="color: #800000">large</span><span style="color: #800000">‘</span>), (<span style="color: #800000">‘</span><span style="color: #800000">t-shirt</span><span style="color: #800000">‘</span>,<span style="color: #800000">‘</span><span style="color: #800000">medium</span><span style="color: #800000">‘</span>),(<span style="color: #800000">‘</span><span style="color: #800000">polo shirt</span><span style="color: #800000">‘</span>,<span style="color: #800000">‘</span><span style="color: #800000">small</span><span style="color: #800000">‘</span><span style="color: #000000">);
  64.         </span><span style="color: #0000ff">set</span><span style="color: #000000">
  65.             集合类型
  66.             A SET column can have a maximum of </span><span style="color: #800080">64</span><span style="color: #000000"> distinct members.
  67.             示例：
  68.                 CREATE TABLE myset (col SET(</span><span style="color: #800000">‘</span><span style="color: #800000">a</span><span style="color: #800000">‘</span>, <span style="color: #800000">‘</span><span style="color: #800000">b</span><span style="color: #800000">‘</span>, <span style="color: #800000">‘</span><span style="color: #800000">c</span><span style="color: #800000">‘</span>, <span style="color: #800000">‘</span><span style="color: #800000">d</span><span style="color: #800000">‘</span><span style="color: #000000">));
  69.                 INSERT INTO myset (col) VALUES (</span><span style="color: #800000">‘</span><span style="color: #800000">a,d</span><span style="color: #800000">‘</span>), (<span style="color: #800000">‘</span><span style="color: #800000">d,a</span><span style="color: #800000">‘</span>), (<span style="color: #800000">‘</span><span style="color: #800000">a,d,a</span><span style="color: #800000">‘</span>), (<span style="color: #800000">‘</span><span style="color: #800000">a,d,d</span><span style="color: #800000">‘</span>), (<span style="color: #800000">‘</span><span style="color: #800000">d,a,d</span><span style="color: #800000">‘</span><span style="color: #000000">);
  70.         DATE
  71.             YYYY</span>-MM-DD（<span style="color: #800080">1000</span>-<span style="color: #800080">01</span>-<span style="color: #800080">01</span>/<span style="color: #800080">9999</span>-<span style="color: #800080">12</span>-<span style="color: #800080">31</span><span style="color: #000000">）
  72.         TIME
  73.             HH:MM:SS（</span><span style="color: #800000">‘</span><span style="color: #800000">-838:59:59</span><span style="color: #800000">‘</span>/<span style="color: #800000">‘</span><span style="color: #800000">838:59:59</span><span style="color: #800000">‘</span><span style="color: #000000">）
  74.         YEAR
  75.             YYYY（</span><span style="color: #800080">1901</span>/<span style="color: #800080">2155</span><span style="color: #000000">）
  76.         DATETIME
  77.             YYYY</span>-MM-DD HH:MM:SS（<span style="color: #800080">1000</span>-<span style="color: #800080">01</span>-<span style="color: #800080">01</span> <span style="color: #800080">00</span>:<span style="color: #800080">00</span>:<span style="color: #800080">00</span>/<span style="color: #800080">9999</span>-<span style="color: #800080">12</span>-<span style="color: #800080">31</span> <span style="color: #800080">23</span>:<span style="color: #800080">59</span>:<span style="color: #800080">59</span><span style="color: #000000">    Y）
  78.         TIMESTAMP
  79.             YYYYMMDD HHMMSS（</span><span style="color: #800080">1970</span>-<span style="color: #800080">01</span>-<span style="color: #800080">01</span> <span style="color: #800080">00</span>:<span style="color: #800080">00</span>:<span style="color: #800080">00</span>/<span style="color: #800080">2037</span> 年某时）
数据类型

 

MySQL知识点整理

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