Re: proposal - assign result of query to psql variable - Mailing list pgsql-hackers

Hello

2013/2/2 Tom Lane <tgl@sss.pgh.pa.us>:
> Shigeru Hanada <shigeru.hanada@gmail.com> writes:
>> On Sat, Feb 2, 2013 at 7:30 PM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
>>> possible variants
>>>
>>> a) don't store NULL  values - and remove existing variable when NULL
>>> be assigned - it is probably best, but should be confusing for users
>>> b) implement flag IS NULL - for variables
>>> c) use nullPrint
>>> d) use empty String
>
>> +1 for a).  If users want to determine whether the result was NULL, or
>> want to use substitute string for NULL result, they can use coalesce
>> in SELECT clause.  Anyway the feature should be documented clearly.
>
> Yeah, I was considering that one too.  Let's do it that way.

updated version

Regards

Pavel

>
>                         regards, tom lane