Re: [SQL] datetime query issue

From: José Soares <jose(at)sferacarta(dot)com>
To: Frank Joerdens <frank(at)x9media(dot)com>
Cc: pgsql-sql(at)postgresql(dot)org
Subject: Re: [SQL] datetime query issue
Date: 1999-08-30 13:04:12
Message-ID: 37CA814B.89F6AB51@sferacarta.com
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Try this:
select extract(year from date) from tablename;
select extract(month from date) from tablename;
select extract(day from date) from tablename;
select extract(hour from date) from tablename;
select extract(minute from date) from tablename;
select extract(minute from date) from tablename;
select extract(second from date) from tablename;

José

Frank Joerdens ha scritto:

> um, this was probably unintelligible. this is the table:
>
> +----------------------------------+----------------------------------+-------+
> | Field | Type | Length|
> +----------------------------------+----------------------------------+-------+
> | source_numeric | int8 not null | 8 |
> | destination_numeric | int8 not null | 8 |
> | source | text not null | var |
> | destination | text not null | var |
> | bytes | int8 not null | 8 |
> | date | datetime | 8 |
> +----------------------------------+----------------------------------+-------+
>
> every hour, a set of rows is added to this table with the current timestamp on
> each row. i guess i need a function to extract the time from datetime. date_trunc
> may be what i am looking for but i couldn't find information in the documentation
> as to how to use these functions.
>
> On Sat, Aug 28, 1999 at 03:35:07PM +0200, Frank Joerdens wrote:
> > I'm not sure how to go about this: I want to find all rows with a timestamp
> > between, say 6 a.m. and 10 p.m. for any number of days. The column format is
> > datetime. How do I extract the 'time of the day' information from this
> > column? What I can think of is to create a view for every single day where datetime
> > is > 6 and < 10 and then another query on all views together but that doesn't sound
> > very elegant and would be a real memory hog for a large number of days.
> >
> > Any better ideas?
> >
> > Thanks
> >
> > Frank
> >
> >
> > ************
>
> ************

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