Message-ID: <01020199fe3f6030-5d953b42-e08d-4782-9da3-3d635f5445af-000000@eu-west-1.amazonses.com>
Date: Sun, 19 Oct 2025 20:53:10 +0000
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Subject: Re: Arrays vs separate tables
To: Rich Shepard <rshepard@appl-ecosys.com>, pgsql-general@postgresql.org
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From: Ray O'Donnell <ray@rodonnell.ie>
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On 19/10/2025 21:43, Rich Shepard wrote:

> In the former book I read that sometimes it's better to have multiple 
> values
> for an atribute in a single row by creating a separate table for that
> attribute rather than using the postgres array capability. The people 
> table
> in my database (1706 rows) has two attributes using the array type
> (direct_phone and email), and only a few indivuals have multiple landline
> phone numbers (cell_phone is a separate column) or email addresses 
> (office
> and personal?). Would it make sense for me to create new landline and 
> email
> address tables and replace the array contents?
>
My experience of doing something similar was that arrays work very well 
for the use-case you describe, as long as you don't have to search 
inside the arrays... I found that, if you have to search for a specific 
value inside an array, then performance really goes out the window. Mind 
you, clever use of an index would probably help here.

Ray.

-- 
Ray O'Donnell // Galway // Ireland
ray@rodonnell.ie