Get big result set from mysql - php

Question

I've a big table with about 20 millions of rows and every day it grows up and I've a form which get a query from this table. Unfortunately query returns hundreds of thousands of rows.
Query is based on Time, and I need all records to classify them by 'clid' base on some rules.So I need all records to do some process on them to make a result table.
This is my table :
CREATE TABLE IF NOT EXISTS `cdr` (
`gid` bigint(20) NOT NULL AUTO_INCREMENT,
`prefix` varchar(20) NOT NULL DEFAULT '',
`id` bigint(20) NOT NULL,
`start` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
`clid` varchar(80) NOT NULL DEFAULT '',
`duration` int(11) NOT NULL DEFAULT '0',
`service` varchar(20) NOT NULL DEFAULT '',
PRIMARY KEY (`gid`),
UNIQUE KEY `id` (`id`,`prefix`),
KEY `start` (`start`),
KEY `clid` (`clid`),
KEY `service` (`service`)
) ENGINE=InnoDB DEFAULT CHARSET=utf-8 ;
and this is my query :
SELECT * FROM `cdr`
WHERE
service = 'test' AND
`start` >= '2014-02-09 00:00:00' AND
`start` < '2014-02-10 00:00:00' AND
`duration` >= 10
Date period could be various from 1 hour to maybe 60 day or even more.(like :
DATE(start) BETWEEN '2013-02-02 00:00:00' AND '2014-02-03 00:00:00'
)
The result set has about 150,000 rows for every day. When i try to get result for bigger period or even one day database crashes.
Does anybody have any idea ?

Answer 1

I don't know how to prevent it from crashing, but one thing that I did with my large tables was partition them by date.
Here, I partition the rows by date, twice a month. As long as your query uses the partitioned column, it will only search the partitions containing the key. It will not do a full table scan.
CREATE TABLE `identity` (
`Reference` int(9) unsigned NOT NULL AUTO_INCREMENT,
...
`Reg_Date` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
PRIMARY KEY (`Reference`),
KEY `Reg_Date` (`Reg_Date`)
) ENGINE=InnoDB AUTO_INCREMENT=28424336 DEFAULT CHARSET=latin1
PARTITION BY RANGE COLUMNS (Reg_Date) (
PARTITION p20140201 VALUES LESS THAN ('2014-02-01'),
PARTITION p20140214 VALUES LESS THAN ('2014-02-14'),
PARTITION p20140301 VALUES LESS THAN ('2014-03-01'),
PARTITION p20140315 VALUES LESS THAN ('2014-03-15'),
PARTITION p20140715 VALUES LESS THAN (MAXVALUE)
);
So basically, you just do a dump of the table, create it with partitions and then import the data into it.