如何将数据类型varchar转换为时间戳mysql？

Question

I have database mysql with table 'tblevel' with column 'waktu' with varchar data type. and the column hold values like this:

30-01-2014 12:19:09

The value will be converted to timestamp, because I have to do that for data viewing in graphic, in this case I use google data visualisation,

The shorted code is :

$result = mysql_query("SELECT TIMESTAMPDIFF(MINUTE,FROM_UNIX_TIMESTAMP(STR_TO_DATE(waktu, '%H:%i:%s %b %d, %Y')), now()) as waktu1,level,press FROM tblevel WHERE TIMESTAMPDIFF(MINUTE,FROM_UNIXTIME(waktu) , now()) < 120 Order By waktu"); 

hope someone help to correct the code .thanks
regards Fixduino.

Answer 1

Try this:

SELECT a.waktu, a.level, a.press 
       TIMESTAMPDIFF(MINUTE, STR_TO_DATE(a.waktu, '%d-%m-%Y %H:%i:%s'), NOW()) AS waktu1           
FROM tblevel a
WHERE TIMESTAMPDIFF(MINUTE, STR_TO_DATE(a.waktu, '%d-%m-%Y %H:%i:%s'), NOW()) < 120 
ORDER BY STR_TO_DATE(a.waktu, '%d-%m-%Y %H:%i:%s'); 

Answer 2

The Date format of MySQL is YMD, try this

SELECT a.waktu, a.level, a.press 
       TIMESTAMPDIFF(MINUTE, STR_TO_DATE(a.waktu, '%y-%M-%d %H:%i:%s'), NOW()) AS waktu1           
FROM tblevel a
WHERE TIMESTAMPDIFF(MINUTE, STR_TO_DATE(a.waktu, '%y-%M-%d %H:%i:%s'), NOW()) < 120 
ORDER BY STR_TO_DATE(a.waktu, '%y-%M-%d %H:%i:%s');