MySQL - 计算具有不同条件的两件事

MySQL - Counting two things with different conditions(MySQL - 计算具有不同条件的两件事)

问题描述

我想在一个查询中计算不同条件下的两件事.

I want to count two things under different conditions in one query.

SELECT COUNT(*) AS count FROM table_name WHERE name = ?

和

SELECT COUNT(*) as count FROM table_name WHERE address = ? AND port = ?

我需要对具有特定地址和特定端口的行进行计数，并对具有特定名称的行进行单独计数.

I need to have a count for rows that have a certain address and certain port, and a SEPARATE count for rows that have a certain name.

我知道我可以做到

SELECT (COUNT*) as count FROM table_name WHERE (address = ? AND port = ?) OR name = ?

不过，这是一次计数，我需要将它们分开，以便向用户显示更准确的消息.

However that is a single count, and I need them to be separate so I can display a more accurate message to the user.

我该怎么做呢?帮助将不胜感激！

How might I go about doing this? Help would be appreciated!

推荐答案

简单点:

SELECT 
    SUM(IF(name = ?, 1, 0)) AS name_count,
    SUM(IF(address = ? AND port = ?, 1, 0)) AS addr_count
FROM 
    table_name

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