Message-ID: <3E42481C.6050705@klaster.net>
Date: Thu, 06 Feb 2003 12:33:48 +0100
From: Tomasz Myrta <jasiek@klaster.net>
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To: Ludwig Lim <lud_nowhere_man@yahoo.com>
Cc: PostgreSQL Mailing List <pgsql-sql@postgresql.org>
Subject: Re: TIME vs. TIMESTAMP data type
References: <20030206110435.27538.qmail@web80303.mail.yahoo.com>
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Ludwig Lim wrote:
> Hi:
> 
>     Are there cases when a TIME data type is a better
> choice over the TIMESTAMP data type? 
> 
>     It seems that PostgreSQL (I'm using 7.2.3)
> encourage its users to use TIMESTAMP over TIME data
> type. I said this because of the following:
>    a) More functions for DATE and TIMESTAMP data types
> such as to_date() and to_timestamp(). Howver, function
> to_time() does not exist.
>    b) Same amount of storage for TIMESTAMP and for
> TIME. Time with time zone even need more storage space
> than a timestamp (12 bytes vs. 8 bytes).
>    c) It's harder to TIMESTAMP to TIME and vice versa,
> while its easier to cast TIMESTAMP to DATE and vice
> versa.
> 
> 
> thank you very much,
> 
> ludwig


Probably you are right, but you can cast into timestamp before using these functions.
Do you really need to care amount of storage?
Don't forget about INTERVAL type, which is very useful for time calculations.

Regards,
Tomasz Myrta