subtracting time

[abs0lut]

I have a field name field1 which data type is datetime in database , I want to subtract it from another field2 with same data type. Could you please help me subtract hours?

[akitchin]

it depends on exactly what result you're looking for.  have a look at the MySQL manual regarding the different date and time functions:

 

http://dev.mysql.com/doc/refman/4.1/en/date-and-time-functions.html

 

of interest might be DATEDIFF().

[MadTechie]

you can't use DATEDIFF() as "Only the date parts of the values are used in the calculation. "

 

i convert to unix time to make my life easier but then again i hate working with dates..

 

Theirs a few ways.. heres one that will give hour minutes and seconds

SELECT FROM_UNIXTIME(UNIX_TIMESTAMP(field1) - UNIX_TIMESTAMP(field2), '%h:%i:%s') as MyTime

[akitchin]

touche, i didn't see the "hours" part.  my mistake.

[PFMaBiSmAd]

TIMEDIFF() will subtract two datetime values and give the result in time (time greater than 24 hours would need to be converted to days by the application code.)

[MadTechie]

touche, i didn't see the "hours" part.  my mistake.

 

Sorry akitchin, kinda revenge for all those misread i have done and had a mod slam me.. no harm intended lol

 

[abs0lut]

thank you