Il est bien gentil mais je ne comprend pas ...
ourriez vous me l'expliquer ?
CODE
Nous vous envoyons cet email pour vous prevenir de l'ajout d'un index, pour
ameliorer les performances de vos requetes.
Sans index, pour chaque requete de ce style, environ 500000 enregistrements
sont parcourus.
mysql> explain select id_url from rs_log_url2 where
mysql> (url='http://www.mondomaine/recette-2043-Corniottes.html'
mysql> AND robot = '10') AND date = '2006-03-21';
+----+-------------+-------------+------+---------------+------+---------+--
----+--------+-------------+
| id | select_type | table | type | possible_keys | key | key_len |
ref | rows | Extra |
+----+-------------+-------------+------+---------------+------+---------+--
----+--------+-------------+
| 1 | SIMPLE | rs_log_url2 | ALL | NULL | NULL | NULL |
NULL | 489224 | Using where |
+----+-------------+-------------+------+---------------+------+---------+--
----+--------+-------------+
mysql> alter table rs_log_url2 add index `i_url_robot_date` (`url`,
mysql> `robot`, `date`);
mysql> explain select id_url from rs_log_url2 where
mysql> (url='http://www.mondomaine.com/recette-2043-Corniottes.html'
mysql> AND robot = '10') AND date = '2006-03-21';
+----+-------------+-------------+------+------------------+----------------
--+---------+-------------------+------+-------------+
| id | select_type | table | type | possible_keys | key
| key_len | ref | rows | Extra |
+----+-------------+-------------+------+------------------+----------------
--+---------+-------------------+------+-------------+
| 1 | SIMPLE | rs_log_url2 | ref | i_url_robot_date |
i_url_robot_date | 265 | const,const,const | 1 | Using where |
+----+-------------+-------------+------+------------------+----------------
--+---------+-------------------+------+-------------+
ameliorer les performances de vos requetes.
Sans index, pour chaque requete de ce style, environ 500000 enregistrements
sont parcourus.
mysql> explain select id_url from rs_log_url2 where
mysql> (url='http://www.mondomaine/recette-2043-Corniottes.html'
mysql> AND robot = '10') AND date = '2006-03-21';
+----+-------------+-------------+------+---------------+------+---------+--
----+--------+-------------+
| id | select_type | table | type | possible_keys | key | key_len |
ref | rows | Extra |
+----+-------------+-------------+------+---------------+------+---------+--
----+--------+-------------+
| 1 | SIMPLE | rs_log_url2 | ALL | NULL | NULL | NULL |
NULL | 489224 | Using where |
+----+-------------+-------------+------+---------------+------+---------+--
----+--------+-------------+
mysql> alter table rs_log_url2 add index `i_url_robot_date` (`url`,
mysql> `robot`, `date`);
mysql> explain select id_url from rs_log_url2 where
mysql> (url='http://www.mondomaine.com/recette-2043-Corniottes.html'
mysql> AND robot = '10') AND date = '2006-03-21';
+----+-------------+-------------+------+------------------+----------------
--+---------+-------------------+------+-------------+
| id | select_type | table | type | possible_keys | key
| key_len | ref | rows | Extra |
+----+-------------+-------------+------+------------------+----------------
--+---------+-------------------+------+-------------+
| 1 | SIMPLE | rs_log_url2 | ref | i_url_robot_date |
i_url_robot_date | 265 | const,const,const | 1 | Using where |
+----+-------------+-------------+------+------------------+----------------
--+---------+-------------------+------+-------------+
Je vois bien qu'il veulent limiter les requetes mais lesquels ? cela va til jouer sur les robots google... et autres ?
Par avance merci .
Cris
