2011-03-15 41 views
2

我有一個簡單的MySQL SELECT語句:MySQL的SELECT COUNT(*)語句不包括minimium值

SELECT COUNT(*) AS COUNT FROM MY_TABLE WHERE TIME_STAMP > ? 

但我並不想算第一/最早的行如果說最早的行TIME_STAMP大於我的WHERE門檻。例如:

SELECT COUNT(*) AS COUNT FROM MY_TABLE WHERE TIME_STAMP > ? AND TIME_STAMP > $earliest 

顯然,我可以通過附加的事先查詢得到最早的TIME_STAMP。但是如果我能在一個人身上做到這一切,我就會在遊蕩。我試過這個,但拋出「無效使用組功能」錯誤:

SELECT COUNT(*) AS COUNT FROM MY_TABLE WHERE TIME_STAMP > ? AND TIME_STAMP > MIN(TIME_STAMP) 

有什麼建議嗎?謝謝

+0

你能否用一個例子說明一下? – Mat 2011-03-15 13:05:24

回答

2

如果您從嵌套選擇中獲得MIN值,那麼您的最後一個查詢將會起作用。組功能需要上下文,你想要什麼最低限度?

SELECT COUNT(*) AS COUNT FROM MY_TABLE WHERE TIME_STAMP > ? AND TIME_STAMP > (SELECT MIN(TIME_STAMP) FROM MY_TABLE) 
+0

當然哦,是的。謝謝 :) – 2011-03-15 13:12:13