Date: Mon, 14 Apr 2014 23:35:53 +0200
From: Vincent Veyron <vincent.veyron@libremen.org>
To: Robert DiFalco <robert.difalco@gmail.com>
Cc: "pgsql-performance@postgresql.org" <pgsql-performance@postgresql.org>,
 "pgsql-general@postgresql.org" <pgsql-general@postgresql.org>
Subject: Re: Approach to Data Summary and Analysis
Message-Id: <20140414233553.626524a7bb8718a451499a7f@libremen.org>
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On Mon, 14 Apr 2014 09:27:29 -0700
Robert DiFalco <robert.difalco@gmail.com> wrote:

> I have several related tables that represent a call state. 
> 
> And so on for calls_connected, calls_completed, call_errors, etc.
> 
> So for my question -- is the choice between these a personal preference
> sort of thing or is there a right or wrong approach? Am I missing another
> approach that would be better?  

Hi Robert,

I guess a call state is subject to change, in which case you would have to shuffle records between tables when that happens?

ISTM you should consider using only a 'calls' table, and add an 'id_call_state' field to it that references the list of possible states. This would make your queries simpler.

create table call_state(
id_call_state text PRIMARY KEY,
libelle text);

INSERT INTO call_state (id_call_state, libelle) VALUES ('calls_connected', 'Connected'), ('calls_completed', 'Completed'), ('call_errors', 'Error');

> CREATE TABLE calls (
>   id      BIGINT NOT NULL, // sequence generator

id_call_state INTEGER NOT NULL REFERENCES call_state,

>   user_id BIGINT NOT NULL,
>   called  TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP,
> 
>   PRIMARY KEY (id),
>   FOREIGN KEY (user_id) REFERENCES my_users(id) ON DELETE CASCADE
> );


-- 
					Regards, Vincent Veyron 

http://libremen.com/ 
Legal case, contract and insurance claim management software


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