MySQL

Posted 2021-02-05 saviour-chu

序号	标题	内容
1	在mysql查询结果中添加自增ID	SELECT (@i :[email protected] + 1) AS i, tabName.* FROM tabName,(SELECT @i := 0) AS t
2	MySQL获取随机结果集	SELECT * FROM tabName ORDER BY RAND() LIMIT 5
3	隐藏手机号码中间四位的方法	SELECT REPLACE(phone, SUBSTR(phone,4,4), ‘XXXX‘) FROM tabName SELECT INSERT(phone, 4, 4, ‘XXXX‘) FROM tabName
4	MySQL的between	SELECT * FROM tabName WHERE id BETWEEN 5 AND 7 SELECT * FROM tabName WHERE id >= 5 AND id <= 7
5	MySQL更新替换	UPDATE tabName SET field=REPLACE(field,‘-01‘,‘-01-31‘)
6	MySQL保留小数	SELECT FORMAT(12562.6655,2);-- 千分位格式，返回值为string SELECT TRUNCATE(4545.1366,2); -- 直接截取不进行四舍五入 SELECT CONVERT(4545.6366,DECIMAL(7,2));-- 预期结果
7
8
9
10