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mysql开窗函数 https://blog.csdn.net/m0_46926492/article/details/124236167
MYSQL开窗函数详解 https://blog.csdn.net/qq_34184505/article/details/125191252

1. (经典)MySQL 常用的拼接语句汇总 https://www.jb51.net/article/194460.htm
2.(经典)Mysql查询表字段结构注释的方式 https://www.jb51.net/database/29608701o.htm
3.MySQL之模糊查询特殊字符处理方式 https://www.jb51.net/database/296921own.htm
4.mysql 批量给数据表和字段添加注释 https://www.jb51.net/database/2955288vo.htm
5.详解mysql数据去重的三种方式 https://www.jb51.net/article/250902.htm
6.详解MySQL中varchar和int隐式转换的注意事项 https://www.jb51.net/database/310125j4g.htm

@@version
show variables like 'version%'
status
mysql --help |grep 'Dist'
select version();
mysql 登录
1. SQL语句大全大全(经典珍藏版)

1. 查看表注释的五种方式
Mysql elt()和INTERVAL(),统计年龄区间多少人 https://blog.csdn.net/qq_60547244/article/details/121074412?spm=1001.2101.3001.6650.2&utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7ERate-2-121074412-blog-113590908.235%5Ev40%5Epc_relevant_3m_sort_dl_base1&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7ERate-2-121074412-blog-113590908.235%5Ev40%5Epc_relevant_3m_sort_dl_base1&utm_relevant_index=5
1. mysql group_concat 拼接字段 https://blog.csdn.net/qq_37159082/article/details/94628277
2. mysql操作字符串 substring(str,m,n) 从m位置开始共n个字符 substr(str,m,n) 从m位置开始到n个字符 left() right() sub_index()
3. MySQL中非常好用的函数或sql语句（14种） https://blog.csdn.net/qq_43614322/article/details/128397187

4.mysql截取字符串函数： https://download.csdn.net/download/weixin_38641150/13697815?spm=1001.2101.3001.6661.1&utm_medium=distribute.pc_relevant_t0.none-task-download-2%7Edefault%7ECTRLIST%7EPaid-1-13697815-blog-128397187.235%5Ev43%5Epc_blog_bottom_relevance_base3&depth_1-utm_source=distribute.pc_relevant_t0.none-task-download-2%7Edefault%7ECTRLIST%7EPaid-1-13697815-blog-128397187.235%5Ev43%5Epc_blog_bottom_relevance_base3&utm_relevant_index=1
5. https://blog.51cto.com/u_15127610/4096414
6.MySQL 进阶 索引 https://blog.csdn.net/I_r_o_n_M_a_n/article/details/124214889
7.Java常用API -- BigDecimal类的用法和注意事项 https://codejiao.blog.csdn.net/article/details/136527776
8.Mysql之mysqldump命令 https://lawson-t.blog.csdn.net/article/details/82284451?spm=1001.2101.3001.6650.3&utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7ERate-3-82284451-blog-128397187.235%5Ev43%5Epc_blog_bottom_relevance_base3&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7ERate-3-82284451-blog-128397187.235%5Ev43%5Epc_blog_bottom_relevance_base3&utm_relevant_index=6
9.[Mysql] RANK()函数 | ROW_NUMBER()函数 | DENSE_RANK()函数 https://blog.csdn.net/Hudas/article/details/124584662
10.

1.mysql清空表数据的两种方式和区别解析 https://www.jb51.net/article/160804.htm
2.MySQL中批量删除指定前缀表的sql语句 https://www.jb51.net/article/39194.htm
3.https://www.jb51.net/article/23964.htm
4.https://www.jb51.net/database/2947270m6.htm
5.mysql序号rownum行号实现方式 https://www.jb51.net/article/270685.htm
6.MySQL避免插入重复记录的方法 https://www.jb51.net/database/299687bnf.htm
7.MySQL中ADD COLUMN添加多个字段的写法实例 https://www.jb51.net/article/275575.htm
8.MySQL删除表数据与MySQL清空表命令的3种方法浅析 https://www.jb51.net/article/259601.htm
9.MySQL删除表操作实现（delete、truncate、drop的区别） https://www.jb51.net/article/175572.htm
10.MySQL数据库高级操作实战(克隆表、清空表、创建临时表及约束) https://www.jb51.net/database/288492ccv.htm#_label5

 

11.MySQL中ADD COLUMN添加多个字段的写法实例 https://www.jb51.net/article/275575.htm
12.错误：
1. MySQL错误代码:1052 Column 'xxx' in field list is ambiguous的原因和解决
2. 解决mysql报错:1264-Out of range value for column ‘字段‘ at row 1
3.解决MySQL报错incorrect datetime value '0000-00-00 00:00:00' for column
4.
13.mysql insert if not exists防止插入重复记录的方法 https://www.jb51.net/article/26934.htm
14.MySQL避免插入重复记录的方法 https://www.jb51.net/database/299687bnf.htm
这三种方法都能避免主键或者唯一索引重复导致的插入失败问题。
insert ignore能忽略重复数据，只插入不重复的数据。
replace into和insert ... on duplicate key update，都是替换原有的重复数据，区别在于replace into是删除原有的行后，
在插入新行，如有自增id，这个会造成自增id的改变；insert ... on duplicate key update在遇到重复行时，
会直接更新原有的行，具体更新哪些字段怎么更新，取决于update后的语句。

15.使用distinct在mysql中查询多条不重复记录值的解决办法 https://www.jb51.net/article/5147.htm
16.MySQL中查询、删除重复记录的方法大全(经典)   https://www.jb51.net/article/116677.htm
17.Mysql语法、特殊符号及正则表达式的使用详解    https://www.jb51.net/article/128241.htm
18.MySQL中with rollup的用法 https://blog.csdn.net/qq_31960623/article/details/115917641
19. SET SQL_SAFE_UPDATES = 0
20.SET @num :=1;
SELECT CAST(@num AS VARCHAR(10));

SET @num1 :='123';
SELECT CAST(@num1 AS INT);

21. MySQL高级进阶sql语句总结大全 https://www.jb51.net/article/240883.htm
22.几个比较重要的MySQL变量 https://www.jb51.net/article/125313.htm
2.3 MySQL详细讲解变量variables的用法 https://www.jb51.net/article/252056.htm

1.MySQL 变量 https://deepinout.com/mysql/mysql-top-articles-mysql/5_j_mysql-variables.html
2.MySQL建表设置默认值的取值范围（经典） https://www.jb51.net/database/302055ty0.htm
3.MySQL中创建表的三种方法汇总（经典） https://www.jb51.net/article/275730.htm
4.mysql实用技巧之比较两个表是否有不同数据的方法分析 https://www.jb51.net/article/177549.htm
5.MySQL如何比较两个表数据的差异（经典） https://www.jb51.net/database/30308279n.htm
6.https://www.jb51.net/database/306439v0a.htm#_label2

1. MySQL中的多字段相同数据去重复 https://www.jb51.net/article/270615.htm
2.MySQL 数据查重、去重的实现语句 https://www.jb51.net/article/195342.htm
3.SQL数据去重的七种方法小结 https://www.jb51.net/database/3178191gy.htm
4.Mysql删除重复的数据 Mysql数据去重复 https://www.jb51.net/article/91279.htm
5.SQL中去除重复数据的几种方法汇总(窗口函数对数据去重) https://www.jb51.net/article/283318.htm
6.MySQL模糊查询语句整理集合 https://www.jb51.net/article/179719.htm
7.MySQL实现模糊查询的高效方法总结(附30条优化建议) https://www.jb51.net/database/317574b0z.htm
8.MySQL不用like+%实现模糊查询 https://www.jb51.net/article/271830.htm
9.mysql中模糊查询的四种用法介绍 https://www.jb51.net/article/48315.htm
10.mysql中写判断语句的方法总结 https://www.jb51.net/article/196309.htm
11.mysql sql常用语句大全 https://www.jb51.net/article/252050.htm
12.MySQL中数据库优化的常见sql语句总结 https://www.jb51.net/article/260282.htm
13.MySQL数据表使用的SQL语句整理 https://www.jb51.net/article/248807.htm
14.MySQL一些常用高级SQL语句详解 https://www.jb51.net/article/250621.htm
15.最新MySQL高级SQL语句大全 https://www.jb51.net/article/253173.htm
16.经典SQL语句大全第1/2页 https://www.jb51.net/article/14634.htm
17.Mybatis超级强大的动态SQL语句大全 https://www.jb51.net/article/249523.htm
18.SQL语句中EXISTS的详细用法大全 https://www.jb51.net/article/252696.htm
19.MySQL高级进阶sql语句总结大全 https://www.jb51.net/article/240883.htm#_lab2_12_3
20.MySQL千万级大表进行数据清理的几种常见方案 https://www.jb51.net/database/303392slb.htm
21. MySQL子查询的几种常见形式介绍 https://www.jb51.net/article/48994.htm
22.简单聊聊Java中线程安全有哪些实现思路? https://blog.csdn.net/m0_71777195/article/details/130654315

1.获取 MySQL 当前月最后一天 https://www.cnblogs.com/shaopang/p/17578280.html