Mysql subquery in a view very slow

Question

I'm trying get last result from a table using the data_coleta (DATE) and servico_id as base. The query is working but is very slow. How can I optimize?

select t1.* from
amostra_ensaio_full t1
where
t1.cliente_id = 6 and t1.tipo_id <> 1
and t1.data_coleta = (SELECT max(s1.data_coleta) from amostra_ensaio_full s1 where t1.cliente_id = s1.cliente_id and s1.tipo_id <> 1 and s1.tipo_id = t1.tipo_id)
and t1.servico_id = (SELECT max(s2.servico_id) from amostra_ensaio_full s2 where t1.cliente_id = s2.cliente_id and s2.tipo_id <> 1 and s2.tipo_id = t1.tipo_id)
GROUP by t1.cliente_id , t1.tipo_id

Answer 1

You can probably speed up this query using indexes.

The query is:

select t1.*
from amostra_ensaio_full t1
where t1.cliente_id = 6 and t1.tipo_id <> 1 and
      t1.data_coleta = (SELECT max(s1.data_coleta)
                        from amostra_ensaio_full s1
                        where t1.cliente_id = s1.cliente_id and 
                              s1.tipo_id <> 1 and
                              s1.tipo_id = t1.tipo_id
                       ) and
     t1.servico_id = (SELECT max(s2.servico_id)
                      from amostra_ensaio_full s2
                      where t1.cliente_id = s2.cliente_id and
                            s2.tipo_id <> 1 and
                            s2.tipo_id = t1.tipo_id
                     )
GROUP by t1.cliente_id , t1.tipo_id;

You want the following index for the query: amostra_ensaio_full(cliente_id, tipo_id, servico_id) .

The condition tipo_id <> 1 is unnecessary in the subquery, but it causes no harm.

Answer 2

Tks Gordon but the query still slow. Maybe I found the answer searching more.

SELECT  a.*
FROM amostra_ensaio_full a 
    INNER JOIN
    (
        SELECT MAX(data_coleta) maxDate , tipo_id, cliente_id 
        FROM amostra_ensaio_full
        GROUP BY cliente_id, tipo_id
    ) b ON a.cliente_id = b.cliente_id and a.tipo_id = b.tipo_id and     b.maxDate = a.data_coleta
GROUP by a.cliente_id ,a.tipo_id