烟柳锁池塘

-- SELECT c.*,t.* FROM course AS c,teacher as t WHERE c.cid=t.-- SELECT s.*,b.* FROM s...

SELECT a.*,b.* FROM stu AS a JOIN jiangjin AS b WHERE b.money in (1000) AND b.id=a....

连接查询包括合并、内连接、外连接和交叉连接，如果涉及多表查询，了解这些连接的特点很重要。 只有真正了解它们之间的区别，才能正确使用。 1、Union UNION 操作符用于...

-- SELECT s.*,j.* FROM student AS s, jiangjin AS j WHERE s.id=j.-- SELECT s.*,j.money ...

SELECT x.*,j.* FROM xueshengbiao AS x,jiangjinbiao AS j WHERE x.id = j....

-- SELECT FORMAT(1.-- SELECT CEIL(2.3),FLOOR(2.-- SELECT ROUND(2....