MySQL將YYYY-MM-DD轉換爲unix時間戳

Question

我想將YYYY-MM-DD列轉換爲unix時間戳。與此問題類似：MySQL - Convert MM/DD/YY to Unix timestamp

MySQL似乎並未將「2012-05-10」的值轉換爲正確的unixtime。以下是建議的功能失敗： SELECT UNIX_TIMESTAMP(CAST(dateid AS DATE)) AS unixtime

Answer 1

您正在使用什麼版本的MySQL？作爲SQLFiddle這兩個查詢測試由MySQL 5.5.27工作

SELECT UNIX_TIMESTAMP(CAST('2012-05-10 00:00:00' AS DATETIME)) As UnixTime; 
SELECT UNIX_TIMESTAMP(CAST('2012-05-10' AS DATE)) As UnixTime; 

SQLFiddle Demo

Answer 2

我不知道您有什麼問題的，可是以下工作正常：

CREATE TABLE ex (dt VARCHAR(20)); 
INSERT INTO ex SET dt = '2012-05-10'; 

SELECT 
UNIX_TIMESTAMP('2012-05-10') ex1, 
UNIX_TIMESTAMP(dt) ex2, 
UNIX_TIMESTAMP(CAST('2012-05-10' AS DATE)) ex3, 
UNIX_TIMESTAMP(CAST(dt AS DATE)) ex4 
FROM ex; 

回報：

+------------+------------+------------+------------+ 
| ex1  | ex2  | ex3  | ex4  | 
+------------+------------+------------+------------+ 
| 1336633200 | 1336633200 | 1336633200 | 1336633200 | 
+------------+------------+------------+------------+ 

正如你所看到的，沒有必要CAST()如果字符串的格式爲YYYY-MM-DD或YYYY-MM-DD HH:MM:SS，則MySQL會將此格式的字符串隱式轉換爲DATE s。

請參閱http://sqlfiddle.com/#!2/1a215/3