Re: [SQL] SELECT using arrays

Herouth Maoz <herouth@oumail.openu.ac.il>

From: Herouth Maoz <herouth@oumail.openu.ac.il>
To: Evan Klinger <evan715@sirius.com>
Cc: pgsql-sql@postgreSQL.org
Date: 1999-07-19T11:48:57Z
Lists: pgsql-hackers
At 00:05 +0300 on 15/07/1999, Evan Klinger wrote:


> I have been playing around with this for some time now to no avail. I
> have a table info with a two-dimensional text type array action. Is
> there any way to select the corresponding value of one of the elements
> without knowing the order of the elements?
>
> E.g.
>
> CREATE TABLE info (action text[][]);
>
> INSERT INTO info VALUES ('{{"VAR","VAL"},{"VAR2","VAL2"}}');
>
> Now what SELECT query will search for "VAR" within action (in this
> case it is the first element, but it may not always be) and print out
> "VAL."
>
>
> Any information would be greatly appreciated.

I think somewhere, somehow, in the Postgres documentation, it should be
written that arrays are only recommended to be used as a bulk, like a
polygon or an image. You can update them or get a particular item in them,
but nothing furter than that.

If you need anything further, don't use arrays, but use the relational data
model and arrange the related data in a related table. Collecting all the
values together is a pretty easy trick from the frontend. So is population
of the table. The said type of searches should become much much easier.

Herouth

--
Herouth Maoz, Internet developer.
Open University of Israel - Telem project
http://telem.openu.ac.il/~herutma