sql - 合并两个 SQL 语句

Question

将两个 SQL 语句合并为一个的最佳方法是什么？

  SELECT MIN(capacity) AS mincapacity, MAX(capacity) AS maxcapacity 
  FROM room

  SELECT MIN(grade) AS mingrade, MAX(grade) AS maxgrade 
  FROM room_grade

提前致谢!

Answer 1

鉴于两个结果集都只包含一行，最简单的方法是交叉连接:

select * from
(SELECT MIN(capacity) AS mincapacity, MAX(capacity) AS maxcapacity FROM room) r
cross join
(SELECT MIN(grade) AS mingrade, MAX(grade) AS maxgrade FROM room_grade) g