Re: Anonymous code block with parameters

On Fri, Sep 19, 2014 at 9:26 AM, Merlin Moncure <mmoncure(at)gmail(dot)com> wrote:
> On Thu, Sep 18, 2014 at 5:22 PM, Hannu Krosing <hannu(at)2ndquadrant(dot)com> wrote:
>> Though it would be even nicer to have fully in-line type definition
>>
>> SELECT (tup).* FROM
>> (
>> SELECT CASE WHEN .. THEN ROW(1,2,3)::(a int, b text, c int2)
>> WHEN .. THEN ROW(2,3,4)
>> ELSE ROW (3,4,5) END AS tup
>> FROM ..
>> ) ss
>
> +1. Workaround at present (which I mostly use during json serialization) is:
>
> SELECT (tup).* FROM
> (
> SELECT CASE WHEN .. THEN
> (SELECT q FROM (SELECT 1, 2, 3) q)
> WHEN .. THEN
> (SELECT q FROM (SELECT 2, 3, 4) q)
> ELSE (SELECT q FROM (SELECT 3, 4, 5) q)
> END AS tup
> FROM ..
> ) ss

actually, this trick *only* works during json serialization -- it
allows control over the column names that row() masks over. trying to
expand (tup).* still gives the dreaded "ERROR: record type has not
been registered". That's because this works:

select (q).* from (select 1 as a, 2 as b) q;

but this doesn't:

select ((select q from (select a,b) q)).* from (select 1 as a, 2 as b) q;

merlin