1.将列中格式化的日期转换成时间戳

UPDATE `teable1` SET dateline2 = UNIX_TIMESTAMP(dateline);

2.替换

//比如你要将表 tb1里面的 f1字段的abc替换为def 
UPDATE tb1 SET f1=REPLACE(f1, 'abc', 'def'); 

3、合计

SELECT Customer,SUM(OrderPrice) FROM Orders
GROUP BY Customer

4、查询某字段长度范围

SELECT * FROM admin WHERE LENGTH(username) > 10 

5、查询表1的数据复制到表2中

CREATE TABLE test1 SELECT * from test2 where 1;