Re: subtracting from a date

I tried that but get an error
v_start_date date;
v_minus_one_year date;

I have v_start_date to start with and want to subtract one year and put
into v_minus_one_year

select v_start_date - interval '1 yr' as v_minus_one_year;

--- I get:

ERROR: query has no destination for result data

On Thu, Feb 6, 2014 at 10:31 AM, Adrian Klaver <adrian(dot)klaver(at)gmail(dot)com>wrote:

> On 02/06/2014 09:25 AM, Jay Vee wrote:
>
>> I have reviewed working with dates documentation but some things are not
>> clear and I cannot get an example to work for what I need.
>>
>> I am passing a date into a stored function like '2013-04-01'
>>
>> The stored function accepts this string as a date type.
>>
>> Within the function, I need to:
>> 1. subtract one year from this date into another date type
>> 2. subtract one month from this date into another date type
>> 3. subtract one day from this date into another date type
>>
>> Are there any examples of this? This is not a timestamp type, but a
>> date type.
>>
>
> Something like this:
>
> test=> select '2013-04-01'::date - interval '1 yr';
> ?column?
> ---------------------
> 2012-04-01 00:00:00
> (1 row)
>
> test=> select '2013-04-01'::date - interval '1 month';
> ?column?
> ---------------------
> 2013-03-01 00:00:00
> (1 row)
>
> test=> select '2013-04-01'::date - interval '1 day';
> ?column?
> ---------------------
> 2013-03-31 00:00:00
>
>
> You did say what language you are using for the function so the assignment
> will depend on that.
>
>
>> thanks
>>
>>
>
> --
> Adrian Klaver
> adrian(dot)klaver(at)gmail(dot)com
>