# 如果要删除相关服务，只需要在“管理员身份”的命令行窗口下面运行:
# sc delete 服务名字

# 将 MySQL 安装为服务的方式:
"C:\Program Files\MariaDB 10.3\bin\mysqld.exe" install MyDB --defaults-file="C:\Program Files\MariaDB 10.3\my.ini"

mysql -u root -p
mysql -uroot -proot
mysql -h 45.42.32.1 -P 9999 -uroot -p

create database bookstore;
create database bookstore character set UTF8; -- 创建时可以指定字符集
use bookstore;  -- 切换到数据库下

-- 特别需要注意，在 MySQL 中，账号由两部分组成:
-- 1. user
-- 2. host
-- 即使 user 相同，只要 host 不同，也会被认为是不同账号。
-- 这样可以非常方便对来自不同 ip 地址的访问进行精细的权限控制。
-- 默认情况下，创建的用户 host 为 ‘%‘，这是一个匹配符，跟模糊查询里的意思一样，表示匹配所有
create user vip identified by ‘vippp‘;             -- 所有连接
create user vip@‘127.0.0.1‘ identified by ‘xxx‘;   -- 本地连接
create user vip@‘192.168.%‘ identified by ‘yyy‘;   -- 192.168 网段的连接

grant all on *.* to vip@‘127.0.0.1‘;        -- 将所有数据库上的所有权利都授予通过本机连接的 vip 用户！
grant all privileges on lagou.* to vip@‘%‘; -- 将数据库 lagou 上的所有权利都授予所有连接的 vip 用户!
grant select on lagou.position to vip@‘%‘;  -- 将 lagou 数据库上的 position 表的访问权限开放给所有 vip 用户。

show grants for vip@‘%‘;

-- 查看用户
select current_user(), user();
select * from mysql.user;

-- 创建与授权
create user ‘xxx‘@‘host‘ identified by ‘密码‘;
grant all on ttt.* to ‘user‘@‘host‘ with grant options;

-- 查看授权情况
show grants for ‘user‘@‘host‘;

-- 用户的管理，删除密码等
set password for ‘user‘@‘host‘ = password(‘新密码‘);
drop user vip;

-- 授权的相对完整语法为:
grant all/alter/create/drop/select/update/delete
      on *.* -- db.*/db.table
      to ‘user‘@‘host‘
      identified by ‘密码‘
      with max_user_connections 2
           max_connections_pser_hour 5;

-- 增加用户
insert into mysql.user(host, user, password) values (xx, yy, zz);

-- 修改密码
update mysql.user set password=password(‘新密码‘) where user=‘vip‘ and host=‘%‘;

-- 修改权限
update mysql.user set event_priv=‘Y‘ where user=‘vip‘ and host=‘%‘;

-- 注意，使用 sql 语句修改用户跟权限之后，需要手动刷新权限表
flush privileges;

-- 查询当前日期
select now(), current_date, current_time;

-- 查询当前用户
select user(), current_user();

-- 数据库
show databases;
use test;

show engines; -- 所有引擎
show plugins; -- 所有插件
show variables; -- 所有系统变量
show variables like ‘%char%‘; -- 可以使用 like 进行过滤, 注意 % _ 的使用
set names utf8; -- 一个快捷方式，用来快速批量设置字符集

show full processlist;
kill 109;

create table book1 (
   bookid int primary key
);
create table book2 (
   bookid int,
   primary key (bookid)
);
create table book3 (
   bookid int auto_increment primary key
);
create table book4 (
   bookid int auto_increment primary key,
   name varchar(30) not null,
   price float check (price >= 0)
);
create table book5 (
   bookid int auto_increment primary key,
   name varchar(30) not null,
   price float check (price >= 0),
   press varchar(50),
   authorid int references author (authorid)
   -- foreign  key(author) references author(authorid),
);
create table book6 (
   bookid int auto_increment,
   name varchar(30) not null,
   price float check (price >= 0),
   press varchar(50),
   authorid int,

   primary key (bookid),
   foreign key (authorid) references author (authorid)
);
create table book7 (
   bookid int auto_increment primary key,
   name varchar(30) not null,
   price float check (price >= 0),
   press varchar(50),
   authorid int
);

create table author (
  authorid int auto_increment,
  name varchar(30) not null,
  tel varchar(20),
  birth date,
  primary key (authorid)
);



-- 实际的导入情况，首先创建表，先不添加任何外键约束
create table book (
   bookid int auto_increment primary key,
   name varchar(30) not null,
   price float check (price >= 0),
   press varchar(50),
   authorid int,
   publish_at datetime,
   created_at timestamp
);
create table author (
  authorid int auto_increment primary key,
  name varchar(30) not null,
  tel varchar(20),
  birth date
);
-- 在这里，执行所有的数据插入操作
-- insert into book ...
-- insert into author ...
alter table book 
   add constraint fk_authorid
   foreign key (authorid)
   references author (authorid);
-- 如果需要添加主键的话，语法如下
alter table book
   add constraint pk_bookid
   primary key (bookid);
-- 如果想删除掉的话
alter table book
   drop foreign key fk_authorid;

create table xxx if not exists (id int);

create temporary table yyy (id int);

create temporary table if not exists yyy (
       id bigint auto_increment,
       name varchar(20) not null unique, -- 唯一，不重复的
       birth datetime,
       gender enum(‘f‘, ‘m‘), -- Female Male
       minzu set(‘汉‘, ‘俄罗斯‘),
       created_at timestamp,
       primary key (id)
);


create table aaa (id int auto_increment primary key, name varchar(20))
   default charset = gbk
   engine = InnoDB
   auto_increment = 7
   comment = `这只是一个测试表而已`;

create table gbk_test2 (vvv varchar(4)) default charset = gbk;
create table gbk_test3 (vvv varchar(4)) default charset = utf8;
insert into gbk_test2 values (‘中国‘);
insert into gbk_test3 values (‘中国‘);
select * from gbk_test2;
select * from gbk_test3;
select length(vvv) from gbk_test2;
select length(vvv) from gbk_test3;
select char_length(vvv) from gbk_test2;
select char_length(vvv) from gbk_test3;

create table char_demo 
(
  aaa char(40),
  bbb varchar(40),
  ccc text(40)
);

insert into char_demo values (‘123‘, ‘123‘, ‘123‘);

select length(aaa), length(bbb), length(ccc) from char_demo;

SET sql_mode = ‘PAD_CHAR_TO_FULL_LENGTH‘;

select length(aaa), length(bbb), length(ccc) from char_demo;

create table person (
       id int auto_increment primary key,
       name varchar(30) not null,
       gender char(2) -- 限制，只有 男、女、未知
);


create table person (
       id int auto_increment primary key,
       name varchar(30) not null,
       gender enum(‘男‘, ‘女‘, ‘未知‘) -- 限制，只有 男、女、未知
);

create table person2 (
       id int auto_increment primary key,
       name varchar(30) not null,
       gender enum(‘男‘, ‘女‘, ‘未知‘), -- 限制，只有 男、女、未知
       country set(‘中国‘, ‘美国‘, ‘南非‘)
);

insert into person3 (name, gender, country) values (‘灭绝‘, ‘女‘, ‘美国,南非‘);

ALTER [ONLINE|OFFLINE] [IGNORE] TABLE tbl_name
    [alter_specification [, alter_specification] ...]
    [partition_options]

alter_specification:
    table_options
  | ADD [COLUMN] col_name column_definition
        [FIRST | AFTER col_name]
  | ADD [COLUMN] (col_name column_definition,...)

  | ADD {INDEX|KEY} [index_name]
        [index_type] (key_part,...) [index_option] ...
  | ADD [CONSTRAINT [symbol]] PRIMARY KEY
        [index_type] (key_part,...) [index_option] ...
  | ADD [CONSTRAINT [symbol]]
        UNIQUE [INDEX|KEY] [index_name]
        [index_type] (key_part,...) [index_option] ...
  | ADD FULLTEXT [INDEX|KEY] [index_name]
        (key_part,...) [index_option] ...
  | ADD SPATIAL [INDEX|KEY] [index_name]
        (key_part,...) [index_option] ...
  | ADD [CONSTRAINT [symbol]]
        FOREIGN KEY [index_name] (col_name,...)
        reference_definition
  | ALGORITHM [=] {DEFAULT|INPLACE|COPY}
  | ALTER [COLUMN] col_name {SET DEFAULT literal | DROP DEFAULT}
  | CHANGE [COLUMN] old_col_name new_col_name column_definition
        [FIRST|AFTER col_name]
  | [DEFAULT] CHARACTER SET [=] charset_name [COLLATE [=] collation_name]
  | CONVERT TO CHARACTER SET charset_name [COLLATE collation_name]
  | {DISABLE|ENABLE} KEYS
  | {DISCARD|IMPORT} TABLESPACE

  | DROP [COLUMN] col_name
  | DROP {INDEX|KEY} index_name
  | DROP PRIMARY KEY
  | DROP FOREIGN KEY fk_symbol

  | FORCE
  | LOCK [=] {DEFAULT|NONE|SHARED|EXCLUSIVE}
  | MODIFY [COLUMN] col_name column_definition
        [FIRST | AFTER col_name]
  | ORDER BY col_name [, col_name] ...
  | RENAME [TO|AS] new_tbl_name
  | ADD PARTITION (partition_definition)
  | DROP PARTITION partition_names
  | TRUNCATE PARTITION {partition_names | ALL}
  | COALESCE PARTITION number
  | REORGANIZE PARTITION partition_names INTO (partition_definitions)
  | EXCHANGE PARTITION partition_name WITH TABLE tbl_name
  | ANALYZE PARTITION {partition_names | ALL}
  | CHECK PARTITION {partition_names | ALL}
  | OPTIMIZE PARTITION {partition_names | ALL}
  | REBUILD PARTITION {partition_names | ALL}
  | REPAIR PARTITION {partition_names | ALL}
  | REMOVE PARTITIONING

key_part:
    col_name [(length)] [ASC | DESC]

index_type:
    USING {BTREE | HASH}

index_option:
    KEY_BLOCK_SIZE [=] value
  | index_type
  | WITH PARSER parser_name
  | COMMENT ‘string‘

table_options:
    table_option [[,] table_option] ...

table_option:
    AUTO_INCREMENT [=] value
  | AVG_ROW_LENGTH [=] value
  | [DEFAULT] CHARACTER SET [=] charset_name
  | CHECKSUM [=] {0 | 1}
  | [DEFAULT] COLLATE [=] collation_name
  | COMMENT [=] ‘string‘
  | CONNECTION [=] ‘connect_string‘
  | {DATA|INDEX} DIRECTORY [=] ‘absolute path to directory‘
  | DELAY_KEY_WRITE [=] {0 | 1}
  | ENGINE [=] engine_name
  | INSERT_METHOD [=] { NO | FIRST | LAST }
  | KEY_BLOCK_SIZE [=] value
  | MAX_ROWS [=] value
  | MIN_ROWS [=] value
  | PACK_KEYS [=] {0 | 1 | DEFAULT}
  | PASSWORD [=] ‘string‘
  | ROW_FORMAT [=] {DEFAULT|DYNAMIC|FIXED|COMPRESSED|REDUNDANT|COMPACT}
  | STATS_AUTO_RECALC [=] {DEFAULT|0|1}
  | STATS_PERSISTENT [=] {DEFAULT|0|1}
  | STATS_SAMPLE_PAGES [=] value
  | TABLESPACE tablespace_name [STORAGE {DISK|MEMORY|DEFAULT}]
  | UNION [=] (tbl_name[,tbl_name]...)

-- 添加列
alter table person add column qq varchar(20);
alter table person add qq varchar(20); -- 可以去掉 column 关键词
alter table person add tel varchar(20) after gender; -- 指定位置
alter table person add (xxx int, yyy int);

-- 修改列
ALTER TABLE t2 MODIFY a TINYINT NOT NULL, CHANGE b c CHAR(20);


-- 删除主键
alter table person change id id int; -- 需要将 auto_increment 去掉
alter table person drop primary key;

-- 增加主键
alter table person add primary key (id);
-- 增加/删除外键
alter table book 
   add constraint fk_authorid
   foreign key (authorid)
   references author (authorid);
-- 增加/删除索引
ALTER TABLE t2 ADD INDEX (d), ADD UNIQUE (a);
-- 重命名
alter table rename to people;

start transaction; -- begin;
savepoint xxx;     -- 存档
rollback;          -- 回滚
rollback to xxx;   -- 回档到某个保存点
commit;            -- 提交事务


-- 创表
create table xxx_inno (id int) engine=InnoDB;
create table xxx_isam (id int) engine=MyISAM;
-- 查看
show create table xxx_inno;
show create table xxx_isam;



-- 查看 xxx_inno 的事务支持情况
-- 首先，开启事务
start transaction;
-- 然后，插入数据
insert into xxx_inno values (111);
insert into xxx_inno values (222);
-- 现在，在其他的连接中，是查询不到这数据的
select * from xxx_inno;
-- 建立保存点(存档)
savepoint s1;
-- 再插入更多数据
insert into xxx_inno values (333);
-- 现在，在当前事务中，可以查到3条数据
select * from xxx_inno;
-- 使用 rollback 回档，将回到插入 333 前的状态
rollback to s1;
-- 提交事务
commit;  
-- 现在，在其他的连接中，就能查询到这些数据了
select * from xxx_inno;



-- 查看 xxx_isam 的事务支持情况
start transaction;
insert into xxx_isam values (666);
-- 在没有 commit 的时候，在其他连接中竟然能查询这数据
-- 说明 MyISAM 是不支持事务的
select * from xxx_isam;

# 数据库备份
mysqldump -uroot -proot > ~/xxx.sql  # > 和 < 是管道语句
mysqldump --all-databases --master-data --single-transaction > ~/xxx.sql
mysqldump -uroot -proot --databases lagou test > ~/lagou.sql

# 数据库恢复
mysql -uroot -proot < ~/xxx.sql
mysql> source ~/xxx.sql

set names utf8;       -- 需要正确的客户端编码

SET autocommit=0;     -- 将自动提交关闭，避免每一条语句都会出发日志写入操作
SET unique_checks=0;  -- 将唯一约束检查关闭
SET foreign_key_checks=0; -- 将外键约束检查关闭


... SQL import statements ...
INSERT INTO yourtable VALUES (1,2), (5,5), ...; -- 尽量使用这种方式的导入语句


COMMIT;             -- 提交事务

-- 恢复设置
set autocommit=1;
SET unique_checks=1;
SET foreign_key_checks=1;

  create table area_demo1 (
    area_id int auto_increment primary key,
    sheng varchar(20) not null,
    shi varchar(20) not null,
    xian varchar(20) not null,
    quhao varchar(20) not null,
    youbian varchar(20),
    jingdu decimal(10, 10),
    weidu decimal(10, 10)
  );

insert into area_demo1 (sheng, shi, xian, quhao) values
  (‘广东省‘, ‘珠海市‘, ‘斗门区‘, ‘22323‘),
  (‘广东省‘, ‘珠海市‘, ‘香洲区‘, ‘22324‘),
  (‘广东省‘, ‘珠海市‘, ‘金湾区‘, ‘22325‘),
  (‘广东省‘, ‘广州市‘, ‘天河区‘, ‘11155‘),
  (‘广东省‘, ‘广州市‘, ‘越秀区‘, ‘11156‘),
  (‘广东省‘, ‘广州市‘, ‘白云区‘, ‘11157‘);

select * from area_demo1 where shi=‘珠海市‘ or shi=‘广州市‘;

select distinct shi from area_demo1 where sheng=‘广东省‘;

select * from area_demo1;

create table s_sheng (pid int auto_increment primary key, p_name varchar(20));
insert into s_sheng (p_name) values (‘广东省‘), (‘山东省‘), (‘广西省‘), (‘湖南省‘);

create table s_shi (sid int auto_increment primary key, s_name varchar(20), sheng int references s_sheng(id));
insert into s_shi (s_name, sheng) values
  (‘珠海市‘, 1), (‘广州市‘, 1), (‘湛江‘, 1),
  (‘桂林市‘, 3), (‘南宁市‘, 3), (‘柳州‘, 3);


create table s_xian (xid int auto_increment primary key, x_name varchar(20), shi int references s_shi(id), youbian varchar(20), jingdu varchar(20), weidu  varchar(20));
insert into s_xian (x_name, shi) values
  (‘斗门区‘,  1), (‘金湾区‘, 1), (‘香洲区‘, 1),
  (‘白云区‘, 2), (‘越秀区‘, 2), (‘天河区‘, 2),
  (‘锦绣区‘, 5), (‘风景区‘, 5);

select * from s_sheng;
select * from s_shi;
select * from s_xian;

delete from s_xian where xid > 8;

-- 全连接，笛卡尔积
select * from s_shi full join s_sheng;

select * from s_shi inner join s_sheng on s_shi.sheng = s_sheng.id;

select * from s_shi s inner join s_sheng t on s.sheng = t.id;

select * from (select * from s_shi s inner join s_sheng t on s.sheng = t.id) w where w.name = ‘广东省‘;

select * from (select * from s_shi s inner join s_sheng t on s.sheng = t.pid) w where w.p_name = ‘广东省‘;


select sid, s_name from (
select s.sid, s.s_name, p.p_name from s_shi s join s_sheng p on s.sheng = p.pid
) a where p_name = ‘广东省‘;

select * from s_xian x
       inner join s_shi s on x.shi = s.sid
       inner join s_sheng sh on s.sheng = sh.pid
where sh.p_name = ‘广东省‘;

select x.* from s_xian x
       join s_shi on s_shi.sid = x.shi
       join s_sheng on s_shi.sheng = s_sheng.pid
    where p_name = ‘广西省‘;

select x.* from s_xian x
       join s_shi on s_shi.sid = x.shi
       where s_name = ‘珠海市‘;

select * from s_sheng;
select * from s_shi;
select * from s_xian;

select x.* from s_xian x, s_shi s, s_sheng p
   where x.shi = s.sid
         and s.sheng = p.pid
         and p.p_name = ‘广西省‘;

select * from s_shi s
  left join s_sheng p on s.sheng = p.pid;


select * from lagou_position_result limit 5;
select * from company_result limit 5;
select * from s_provinces limit 5;

select count(*) from lagou_position_result;


desc s_provinces;
select * from s_sheng limit 1;
select * from s_shi limit 1;
select * from s_provinces limit 5;

select * from lagou_position_result order by salary_min desc limit 10;

CREATE TABLE `s_provinces` (
  `id` int(11) NOT NULL,
  `cityName` varchar(30) NOT NULL,
  `parentId` int(11) NOT NULL,
  `shortName` varchar(30) NOT NULL,
  `depth` int(1) NOT NULL,
  `cityCode` varchar(4) NOT NULL,
  `zipCode` varchar(6) NOT NULL,
  `mergerName` varchar(50) NOT NULL,
  `longitude` varchar(16) NOT NULL,
  `latitude` varchar(16) NOT NULL,
  `pinyin` varchar(30) NOT NULL,
  `isUse` int(1) unsigned zerofill DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8

-- 所有县
select x.id, p.cityName, s.cityName, x.cityName
from s_provinces x
       join s_provinces s on x.parentId = s.id
       join s_provinces p on s.parentId = p.id
where p.cityName = ‘广东省‘;

-- 所有市
select x.id, p.cityName, s.cityName, x.cityName
from s_provinces x
       join s_provinces s on x.parentId = s.id
       join s_provinces p on s.parentId = p.id
where p.cityName = ‘广东省‘
union all
select s.id, p.cityName, s.cityName, null from s_provinces s
       join s_provinces p on s.parentId = p.id
where p.cityName = ‘广东省‘;

DROP TABLE IF EXISTS emp;

CREATE TABLE emp (
  empno decimal(4,0) NOT NULL,
  ename varchar(10) default NULL,
  job varchar(9) default NULL,
  mgr decimal(4,0) default NULL,
  hiredate date default NULL,
  sal decimal(7,2) default NULL,
  comm decimal(7,2) default NULL,
  deptno decimal(2,0) default NULL
);

DROP TABLE IF EXISTS dept;

CREATE TABLE dept (
  deptno decimal(2,0) default NULL,
  dname varchar(14) default NULL,
  loc varchar(13) default NULL
);

INSERT INTO emp VALUES (‘7369‘,‘SMITH‘,‘CLERK‘,‘7902‘,‘1980-12-17‘,‘800.00‘,NULL,‘20‘);
INSERT INTO emp VALUES (‘7499‘,‘ALLEN‘,‘SALESMAN‘,‘7698‘,‘1981-02-20‘,‘1600.00‘,‘300.00‘,‘30‘);
INSERT INTO emp VALUES (‘7521‘,‘WARD‘,‘SALESMAN‘,‘7698‘,‘1981-02-22‘,‘1250.00‘,‘500.00‘,‘30‘);
INSERT INTO emp VALUES (‘7566‘,‘JONES‘,‘MANAGER‘,‘7839‘,‘1981-04-02‘,‘2975.00‘,NULL,‘20‘);
INSERT INTO emp VALUES (‘7654‘,‘MARTIN‘,‘SALESMAN‘,‘7698‘,‘1981-09-28‘,‘1250.00‘,‘1400.00‘,‘30‘);
INSERT INTO emp VALUES (‘7698‘,‘BLAKE‘,‘MANAGER‘,‘7839‘,‘1981-05-01‘,‘2850.00‘,NULL,‘30‘);
INSERT INTO emp VALUES (‘7782‘,‘CLARK‘,‘MANAGER‘,‘7839‘,‘1981-06-09‘,‘2450.00‘,NULL,‘10‘);
INSERT INTO emp VALUES (‘7788‘,‘SCOTT‘,‘ANALYST‘,‘7566‘,‘1982-12-09‘,‘3000.00‘,NULL,‘20‘);
INSERT INTO emp VALUES (‘7839‘,‘KING‘,‘PRESIDENT‘,NULL,‘1981-11-17‘,‘5000.00‘,NULL,‘10‘);
INSERT INTO emp VALUES (‘7844‘,‘TURNER‘,‘SALESMAN‘,‘7698‘,‘1981-09-08‘,‘1500.00‘,‘0.00‘,‘30‘);
INSERT INTO emp VALUES (‘7876‘,‘ADAMS‘,‘CLERK‘,‘7788‘,‘1983-01-12‘,‘1100.00‘,NULL,‘20‘);
INSERT INTO emp VALUES (‘7900‘,‘JAMES‘,‘CLERK‘,‘7698‘,‘1981-12-03‘,‘950.00‘,NULL,‘30‘);
INSERT INTO emp VALUES (‘7902‘,‘FORD‘,‘ANALYST‘,‘7566‘,‘1981-12-03‘,‘3000.00‘,NULL,‘20‘);
INSERT INTO emp VALUES (‘7934‘,‘MILLER‘,‘CLERK‘,‘7782‘,‘1982-01-23‘,‘1300.00‘,NULL,‘10‘);

INSERT INTO dept VALUES (‘10‘,‘ACCOUNTING‘,‘NEW YORK‘);
INSERT INTO dept VALUES (‘20‘,‘RESEARCH‘,‘DALLAS‘);
INSERT INTO dept VALUES (‘30‘,‘SALES‘,‘CHICAGO‘);
INSERT INTO dept VALUES (‘40‘,‘OPERATIONS‘,‘BOSTON‘);