[servil]

נניח לשאילתה הזו:

PHP קוד:

EXPLAIN SELECT * FROM (SELECT * FROM `rishum` WHERE `status`!='not_relevant' AND `city`='2' AND `rishum_to`='1' AND `aougust_form`='0' AND `date`>='2014/04/22' AND `date`<='2015/04/21') as c GROUP BY `talmid_id` 


שהמבנה שלה מופיע ברוב השאילתות בקוד...אני מקבל:

SQL result

Host: localhost
Database: shai_mask
Generation Time: Aug 01, 2014 at 07:52 AM
Generated by: phpMyAdmin 3.5.8.2 / MySQL 5.5.31
SQL query: EXPLAIN SELECT * FROM (SELECT * FROM `rishum` WHERE `status`!='not_relevant' AND `city`='2' AND `rishum_to`='1' AND `aougust_form`='0' AND `date`>='2014/04/22' AND `date`<='2015/04/21') as c GROUP BY `talmid_id`; 
Rows: 2

id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	<derived2>	ALL	NULL	NULL	NULL	NULL	2535	Using temporary; Using filesort
2	DERIVED	rishum	ALL	NULL	NULL	NULL	NULL	11479	Using where