MySQL - Optimization select query - mysql

Question

My query is taking 5 seconds to finish but it sounds to much for something so basic. I did an explain query:
https://www.dropbox.com/s/18pedm9n5fssz4e/localhost%20_%20localhost%20_%20logrede%20_%20phpMyAdmin%203.4.11.pdf
It is possible to you to help me optimize it?
Thanks :)

Answer 1

I've restructured the query using JOINs instead of a less readable WHERE clause. I see everything is based on the primary "material" table. So, my first suggestion is to use the "STRAIGHT_JOIN" clause to tell MySQL to do the query in the order you have listed.... otherwise, sometimes it tries to think for you and do some things in what could be an alternate "primary" table driving the query. All your other tables are basically "lookup values" tables.
Secondly... On each of the tables, I would specifically have the following indexes on the tables. I'm sure you already had on the primary keys of each table... but since your GROUP_CONCAT are getting a corresponding descriptive field from the table, I would include that column in the index. Here's the other reason... When a query is run and using the index, if the query does not have to go back to the raw table for the "other" columns, it doesn't have to. So, by having the description as part of the index, it can do the join AND get the description both from the index...
I would have an index on
material ( cdomaterial )
cliente ( idcliente, nome )
classeobra ( idclasse, sigla )
dma ( iddma, nome )
desenho( iddesenho, nome )
fornecedor ( idfornecedor, nome )
modelo ( idmodelo, nome )
fabricante ( idfabri, nome )
fornecido( codmaterial, preco )
unidade( idunidade, sigla )
tipofornecimento( idtipoforn, sigla )
So, the above said, I would run the following query...
SELECT STRAIGHT_JOIN
material.codmaterial,
cliente.nome as cliente,
tipofornecimento.sigla as fornecimento,
unidade.sigla as unidade,
GROUP_CONCAT(DISTINCT classeobra.sigla ORDER BY classeobra.idclasse SEPARATOR ', ') as classeobra,
GROUP_CONCAT(DISTINCT dma.nome ORDER BY dma.iddma SEPARATOR ', ') as dma,
GROUP_CONCAT(DISTINCT desenho.nome ORDER BY desenho.iddesenho SEPARATOR ', ') as desenho,
GROUP_CONCAT(DISTINCT fornecedor.nome ORDER BY fornecedor.idfornecedor SEPARATOR ', ') as fornecedor,
GROUP_CONCAT(DISTINCT modelo.nome ORDER BY modelo.idmodelo SEPARATOR ', ') as modelo,
GROUP_CONCAT(DISTINCT fabricante.nome ORDER BY fabricante.idfabri SEPARATOR ', ') as marca,
GROUP_CONCAT(DISTINCT fornecido.preco ORDER BY fornecido.preco SEPARATOR ', ') as preco
FROM
material
JOIN unidad
ON material.idunidade = unidade.idunidade
JOIN requisitado
ON material.codmaterial = requisitado.codmaterial
JOIN cliente
ON requisitado.idcliente = cliente.idcliente
JOIN tipofornecimento
ON requisitado.idtipoforn = tipofornecimento.idtipoforn
JOIN possuimodelo
ON material.codmaterial = possuimodelo.codmaterial
JOIN modelo
ON possuimodelo.idmodelo = modelo.idmodelo
JOIN pertence,
ON modelo.idmodelo = pertence.idmodelo
JOIN fabricante
ON pertence.idfabri = fabricante.idfabri
JOIN utilizadoclasseobra
ON material.codmaterial = utilizadoclasseobra.codmaterial
JOIN classeobra
ON utilizadoclasseobra.idclasse = classeobra.idclasse
JOIN possuidma
ON material.codmaterial = possuidma.codmaterial
JOIN dma
ON possuidma.iddma = dma.iddma
JOIN fornecido
ON material.codmaterial = fornecido.codmaterial
JOIN fornecedor
ON fornecido.idfornecedor = fornecedor.idfornecedor
JOIN possuidesenho
ON material.codmaterial = possuidesenho.codmaterial
JOIN desenho
ON possuidesenho.iddesenho = desenho.iddesenho
GROUP BY
material.codmaterial,
cliente.nome
ORDER BY
material.codmaterial ASC,
cliente.nome ASC ;