sql - 除法结果为零时返回字符串

我有一个这样的SQL查询：

SELECT
u.id,
tu.score/(CASE tu.mo_count  WHEN 0 THEN NULL ELSE tu.mo_count END) AS score_avg
FROM tournament_userscore tu
INNER JOIN users u ON u.id = tu.user_id
WHERE tournament_id = 1
ORDER BY tu.score DESC

当tu.mo_count为零时，将替换空值而不是零。如何为此行设置类似'EMPTY'的字符串：

tu.score/(CASE tu.mo_count  WHEN 0 THEN NULL ELSE tu.mo_count END) AS score_avg

我的意思是当除法结果为零或为空时，我想返回“anything”字符串。

最佳答案

尝试将CASE-语句移到外部：

SELECT
u.id,
CASE WHEN tu.mo_count = 0 THEN 'EMPTY' ELSE (tu.score/tu.mo_count)::text END as score_avg
FROM tournament_userscore tu
INNER JOIN users u ON u.id = tu.user_id
WHERE tournament_id = 1
ORDER BY tu.score DESC