From: | Joe Conway <mail(at)joeconway(dot)com> |
---|---|
To: | elein <elein(at)varlena(dot)com> |
Cc: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Pavel Stehule <stehule(at)kix(dot)fsv(dot)cvut(dot)cz>, pgsql-general(at)postgresql(dot)org |
Subject: | Re: join of array |
Date: | 2003-08-15 17:06:36 |
Message-ID: | 3F3D131C.90909@joeconway.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-general pgsql-patches |
elein wrote:
>> ARRAY[[1,2],[3,4]] || ARRAY[[1,2],[3,4]] ==
>> '{{{1,2},{3,4}},{{1,2},{3,4}}}'
>>
>>I think the first two still make sense. I guess the third case ought to be:
>> ARRAY[[1,2],[3,4]] || ARRAY[[1,2],[3,4]] ==
>> '{{1,2},{3,4},{1,2},{3,4}}'
>>?
>
> I do not think this is right. I think the current behaviour
> is right. You are effectively dereferencing or flattening
> the second array which changes the definition of the second
> object.
It makes sense in analogy to
ARRAY[1,2] || ARRAY[3,4] == '{1,2,3,4}'
In the case of, e.g. ARRAY[[1,2],[3,4]] || ARRAY[[5,6],[7,8]],
'{1,2}', '{3,4}', '{5,6}', and '{7,8}' are "elements" of the higher
level array, just like 1, 2, 3, & 4 are elements of '{1,2,3,4}'
Joe
From | Date | Subject | |
---|---|---|---|
Next Message | Jenny Zhang | 2003-08-15 17:10:20 | getting execution plans with multiple database connections |
Previous Message | Stephan Szabo | 2003-08-15 16:57:24 | Re: importing db as text files |
From | Date | Subject | |
---|---|---|---|
Next Message | expect | 2003-08-15 17:18:44 | summary and request |
Previous Message | elein | 2003-08-15 16:54:43 | Re: join of array |