Subject AW: [firebird-support] How to do Time calculation
Author Steffen Heil

First make sure, no employee is working during daylight saving switching. Firebird is unfortunately incapable of handling this correctly if you don't store you dates and times in utc (or any other timezone not having daylight savings). You will miss one hour per employee or get an additional hour...

If you safe you dates and times in your timezone and this timezone contains daylight savings and you might have employees working at switching times, you need to do these calculations in your application, you cannot rely on firebird. (Note that you will also loose information!)
(Unfortunately, these restrictions seem inacceptable for any real life generic applications...)


-----Urspr√ľngliche Nachricht-----
Von: [] Im Auftrag von Vishal Tiwari
Gesendet: Freitag, 18. Dezember 2009 12:44
Betreff: [firebird-support] How to do Time calculation

Hi All,

I have one small question(doubt) that how to subtract time.

Let me explain in detail:

I have one table, say "Test_Data" and I have three fields as follows:

1) EmpNo Varchar(15)
2) dtDate Date
3) tmTime Time

This table will contain entry time as well as exit time for a perticual day for a perticular employee. Now here i want to calculate the total time employees worked for given two different dates or two same dates, how do i achieve this.

Thanks In Advance.

Vishal Tiwari...

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