The `problem` is that i dont know if having so many indexes will raise
problems as the data dimension grown.
And i am not even sure that this design is truly reliable;
For example, if i would to know how many employees have every company,
i'll have to run that query:
-----
EXPLAIN ANALYZE
SELECT
c.id,
c.company_name,
count(e.id) AS num_employee
FROM
contact AS c
LEFT JOIN contact AS e ON (c.id = e.id_company)
WHERE c.tipo = 'company'
GROUP BY c.id, c.company_name
-----
That seem to be not very efficient: http://explain.depesz.com/s/Q0m
(I loaded some test data from http://www.generatedata.com/#generator,
so now i have 23893 rows in the table.. oh, i added a index on the
'kind' (tipo) column too)
On 23 Giu, 13:47, gryz...@xxxxxxxxx (Grzegorz Jaśkiewicz) wrote:
> it looks ok on explain, that is - the cost isn't too high.
> So what's the problem ?
>
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