mySQL计数字符串的出现次数

Question

我有这个问题......

SELECT SUM(brownlow_votes) AS votes, 
player_id, 
player_name, 
player_team, 
COUNT(*) AS vote_count 
FROM afl_brownlow_phantom, afl_playerstats 
WHERE player_id=brownlow_player 
AND brownlow_match=player_match 
GROUP BY player_id 
ORDER BY votes DESC LIMIT 50

因此“投票”成为玩家拥有的投票数，“vote_count”成为玩家投票的次数（匹配）。这很好。

但是，我有另一个名为“brownlow_lock”的列，它是空白或“Y”。如何获得'Y'的出现次数？我知道我可以解决这个问题，将它改为0或1，只是做一个SUM（），但我不想去编辑插入数据的大量页面。

Answer 1

如果我理解正确你就需要添加

COUNT(CASE WHEN brownlow_lock='Y' THEN 1 END) AS Cnt

到您的查询

Answer 2

尝试使用IF control flow function

  

SELECT SUM（IF（brownlow_lock ='Y'，1,0））lock_count ...