mysql - 将 3 个查询优化为一个查询的最佳方法

Question

假设我有以下查询。

SELECT count(*) FROM info WHERE info = 'a' and uid = 1
SELECT count(*) FROM info WHERE info = 'b' and uid = 1
SELECT count(*) FROM info WHERE info = 'c' and uid = 1;

有什么方法可以在一个查询中获取所有这些详细信息，而不是编写 3 个查询？

Answer 1

SELECT info, count(*) as info_cnt 
FROM T
WHERE uid = 1 and info IN ('a', 'b','c')
GROUP BY info