mysql - How to index a table fields -

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i developing large table messages inbox query like

explain select * messages (receptor='x1@yahoo.com' , sender='x2@yahoo.com') or (sender='x1@yahoo.com' , receptor='x2@yahoo.com') order id desc limit 10;

is slow , cause hang server please, let me know how index table or change query avoid problem thanks

table structure

mysql> describe messages;                   +----------+--------------+------+-----+---------+----------------+ | field    | type         | null | key | default |          | +----------+--------------+------+-----+---------+----------------+ | id       | bigint(20)   | no   | pri | null    | auto_increment |  | sender   | varchar(65)  | no   | mul | null    |                |  | is_sdel  | tinyint(1)   | no   |     | null    |                |  | receptor | varchar(65)  | no   | mul | null    |                |  | is_rdel  | tinyint(1)   | no   |     | null    |                |  | dtime    | varchar(100) | no   | mul | null    |                |  | title    | longtext     | no   |     | null    |                |  | com      | longtext     | no   |     | null    |                |  | ipu      | varchar(15)  | no   |     | null    |                |  | flage    | tinyint(2)   | no   |     | null    |                |  | view     | tinyint(2)   | no   | mul | null    |                |  +----------+--------------+------+-----+---------+----------------+ 11 rows in set (0.00 sec)

explain command result

 explain select * messages (receptor='x1@yahoo.com' , sender='x2@yahoo.com') or (sender='x1@yahoo.com' , receptor='x2@yahoo.com') order id desc limit 10; +----+-------------+----------+-------+--------------------------------------------------------------------------------+--------------------+---------+------+------+-----------------------------+ | id | select_type | table    | type  | possible_keys                                                                  | key                | key_len | ref  | rows |                       | +----+-------------+----------+-------+--------------------------------------------------------------------------------+--------------------+---------+------+------+-----------------------------+ |  1 | simple      | messages | range | sender,receptor,receptor-id,receptor-view,sender-receptor-id,sender-is_sdel-id | sender-receptor-id | 134     | null |    4 | using where; using filesort |  +----+-------------+----------+-------+--------------------------------------------------------------------------------+--------------------+---------+------+------+-----------------------------+ 1 row in set (0.01 sec)

submitting answer comments:

select * (   select * messages   (receptor='x1@yahoo.com' , sender='x2@yahoo.com')     or (sender='x1@yahoo.com' , receptor='x2@yahoo.com') ) x order id desc limit 10;

the problem experienced sorting big table. solution forces mysql first filter out messages in inner query, , sort these in outer query.


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