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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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