RE: How do I select composite array element that satisfy specific conditions. - Mailing list pgsql-general

Hi

> -----Original Message-----
> From: a [mailto:372660931@qq.com]
> Sent: Mittwoch, 23. Mai 2018 11:43
> To: pgsql-general <pgsql-general@postgresql.org>
> Subject: How do I select composite array element that satisfy specific conditions.
> 
> Hi, say if I have composite type and table
> 
> create type A as(
>      x float8,
>      y float8
> );
> 
> create table B(
>      Ay A[]
> );
> 
> insert into B
> values(array[
>      (1,2)::A,
>      (3,4)::A]
> );
> 
> How could I select the element of Ay that satisfy x=3??
> 
> Thank you so much!!
> 
> Shore

I did not really follow this thread, so I am not in clear, why you want to complicate your life that much.
You create a custom data type and then use it in an array in a column. A complex hierarchical structure.
Why don't you simply use JSON or JSONB? Your example sounds terribly academic very much like a school assignment.

Bye
Charles