Re: precedence of operators

[Jean Beaulieu]

Rick James Wrote:
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> Let's see the indexes (SHOW CREATE TABLE) and the
> real WHERE clause. Also, do EXPLAIN SELECT ...;
> that will show whether it will use any of the
> indexes.
>
> If you have a million rows, I'll show you a way to
> make the geolocation code run _much_ faster.
> If you have a thousand rows, I'll bet you can't
> see any significant difference when benchmarking
> your two choices of ordering ANDs.

Thanks a lot for the answer! I may have 100,000 rows after a year, not a million, but 300,000 could be possible in the long run.
The where clause is not static, it varies, depending of the user input. The geolocation clause however will be a test within a range (longitude and latitude), fortunately there is a field province/state (within a country) that I can add in the AND clause, I have the feeling that it will make it much faster than an arithmetic operation.
An example of an sql statement that was generated by my php code (and executed):

SELECT * FROM `robot1` where type=1 AND `choix_port_robot`=27 AND (`bout_nez`=1 OR `bout_nez`=-1 ) AND `oeil_au_beur_noir`=0 AND (( `pelage`=3 AND ( (`couleur1`=3 AND `couleur2`=4) OR ( `couleur2`=3 AND `couleur1`=4)) ) OR (`pelage`=2 AND ((`couleur1`=3 AND (`couleur2`=4 OR `couleur2`=5) ) OR ( `couleur2`=3 AND (`couleur1`=4 OR `couleur1`=5) ))) ) AND (`pelage`=2 OR `pelage`=3) AND ( `latitude` > 45.2162875455 AND `latitude` < 46.1253784545 AND `longitude` > -74.166362 AND `longitude` < -72.916362) AND (`masque_tabby`=-1 OR `masque_tabby`=0)