2013/2/2 Shigeru Hanada <shigeru.hanada@gmail.com>:
> 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.
>
yes, this has one other advantage - it doesn't block possible
enhancing variables about NULL support in future. And other - it
doesn't depends on psql settings
Regards
Pavel
> --
> Shigeru HANADA