Re: How to inquiry a nest result?

On 10 November 2011 15:43, shuaixf <shuaixf(at)gmail(dot)com> wrote:
> --*Test SQL*
> CREATE TABLE tb(id integer primary key,
>                name varchar(32),
>                parent integer);
>
> INSERT INTO tb VALUES(1, 'iPhone',    NULL);
> INSERT INTO tb VALUES(2, 'HTC',       NULL);
> INSERT INTO tb VALUES(3, 'Motorola',  NULL);
> INSERT INTO tb VALUES(4, 'iPhone3GS', 1);
> INSERT INTO tb VALUES(5, 'G7',        2);
> INSERT INTO tb VALUES(6, 'G8',        2);
> INSERT INTO tb VALUES(7, 'iPhone4',   1);
> INSERT INTO tb VALUES(8, 'iPhone4-white', 7);
> INSERT INTO tb VALUES(9, 'iPhone4-black', 7);
> INSERT INTO tb VALUES(10,'G7-A',      5);
> INSERT INTO tb VALUES(11,'G7-B',      5);
>
> *How to create a SQL to inquiry the result like this:*
> id       name
> ----------------
>  1        iPhone
>  4        iPhone3GS
>  7        iPhone4S
>  8        iPhone4S-white
>  9        iPhone4S-black
>  2        HTC
>  5        G7
> 10        G7-A
> 11        G7-B
>  3        Motorola
>
> Thank you very much!
>
>
>
>
> --
> View this message in context: http://postgresql.1045698.n5.nabble.com/How-to-inquiry-a-nest-result-tp4981259p4981259.html
> Sent from the PostgreSQL - general mailing list archive at Nabble.com.

You can do that with a recursive CTE (common table expression). See
the documentation for SELECT in versions 8.4 or later, which contains
examples of queries like these.

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