I was googling, self-educating & looking for solution for hours but with no luck. I found a few similar questions here but not this case.
My tables:
- persons (~10M rows)
- attributes (location, age,…)
- links (M:M) between persons and attributes (~40M rows)
Situation:
I try to select all person ids (person_id) from some locations (location.attribute_value BETWEEN 3000 AND 7000), being some gender (gender.attribute_value = 1), born in some years (bornyear.attribute_value BETWEEN 1980 AND 2000) and having some eyes' color (eyecolor.attribute_value IN (2,3)).
This is my query witch tooks 3~4 min. and I'd like to optimize:
SELECT person_id
FROM person
LEFT JOIN attribute location ON location.attribute_type_id = 1 AND location.person_id = person.person_id
LEFT JOIN attribute gender ON gender.attribute_type_id = 2 AND gender.person_id = person.person_id
LEFT JOIN attribute bornyear ON bornyear.attribute_type_id = 3 AND bornyear.person_id = person.person_id
LEFT JOIN attribute eyecolor ON eyecolor.attribute_type_id = 4 AND eyecolor.person_id = person.person_id
WHERE 1
AND location.attribute_value BETWEEN 3000 AND 7000
AND gender.attribute_value = 1
AND bornyear.attribute_value BETWEEN 1980 AND 2000
AND eyecolor.attribute_value IN (2,3)
LIMIT 100000;
Result:
+-----------+
| person_id |
+-----------+
| 233 |
| 605 |
| ... |
| 8702599 |
| 8703617 |
+-----------+
100000 rows in set (3 min 42.77 sec)
Explain extended:
+----+-------------+----------+--------+---------------------------------------------+-----------------+---------+--------------------------+---------+----------+--------------------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | filtered | Extra |
+----+-------------+----------+--------+---------------------------------------------+-----------------+---------+--------------------------+---------+----------+--------------------------+
| 1 | SIMPLE | bornyear | range | attribute_type_id,attribute_value,person_id | attribute_value | 5 | NULL | 1265229 | 100.00 | Using where |
| 1 | SIMPLE | location | ref | attribute_type_id,attribute_value,person_id | person_id | 5 | test1.bornyear.person_id | 4 | 100.00 | Using where |
| 1 | SIMPLE | eyecolor | ref | attribute_type_id,attribute_value,person_id | person_id | 5 | test1.bornyear.person_id | 4 | 100.00 | Using where |
| 1 | SIMPLE | gender | ref | attribute_type_id,attribute_value,person_id | person_id | 5 | test1.eyecolor.person_id | 4 | 100.00 | Using where |
| 1 | SIMPLE | person | eq_ref | PRIMARY | PRIMARY | 4 | test1.location.person_id | 1 | 100.00 | Using where; Using index |
+----+-------------+----------+--------+---------------------------------------------+-----------------+---------+--------------------------+---------+----------+--------------------------+
5 rows in set, 1 warning (0.02 sec)
Profiling:
+------------------------------+-----------+
| Status | Duration |
+------------------------------+-----------+
| Sending data | 3.069452 |
| Waiting for query cache lock | 0.000017 |
| Sending data | 2.968915 |
| Waiting for query cache lock | 0.000019 |
| Sending data | 3.042468 |
| Waiting for query cache lock | 0.000043 |
| Sending data | 3.264984 |
| Waiting for query cache lock | 0.000017 |
| Sending data | 2.823919 |
| Waiting for query cache lock | 0.000038 |
| Sending data | 2.863903 |
| Waiting for query cache lock | 0.000014 |
| Sending data | 2.971079 |
| Waiting for query cache lock | 0.000020 |
| Sending data | 3.053197 |
| Waiting for query cache lock | 0.000087 |
| Sending data | 3.099053 |
| Waiting for query cache lock | 0.000035 |
| Sending data | 3.064186 |
| Waiting for query cache lock | 0.000017 |
| Sending data | 2.939404 |
| Waiting for query cache lock | 0.000018 |
| Sending data | 3.440288 |
| Waiting for query cache lock | 0.000086 |
| Sending data | 3.115798 |
| Waiting for query cache lock | 0.000068 |
| Sending data | 3.075427 |
| Waiting for query cache lock | 0.000072 |
| Sending data | 3.658319 |
| Waiting for query cache lock | 0.000061 |
| Sending data | 3.335427 |
| Waiting for query cache lock | 0.000049 |
| Sending data | 3.319430 |
| Waiting for query cache lock | 0.000061 |
| Sending data | 3.496563 |
| Waiting for query cache lock | 0.000029 |
| Sending data | 3.017041 |
| Waiting for query cache lock | 0.000032 |
| Sending data | 3.132841 |
| Waiting for query cache lock | 0.000050 |
| Sending data | 2.901310 |
| Waiting for query cache lock | 0.000016 |
| Sending data | 3.107269 |
| Waiting for query cache lock | 0.000062 |
| Sending data | 2.937373 |
| Waiting for query cache lock | 0.000016 |
| Sending data | 3.097082 |
| Waiting for query cache lock | 0.000261 |
| Sending data | 3.026108 |
| Waiting for query cache lock | 0.000026 |
| Sending data | 3.089760 |
| Waiting for query cache lock | 0.000041 |
| Sending data | 3.012763 |
| Waiting for query cache lock | 0.000021 |
| Sending data | 3.069694 |
| Waiting for query cache lock | 0.000046 |
| Sending data | 3.591908 |
| Waiting for query cache lock | 0.000060 |
| Sending data | 3.526693 |
| Waiting for query cache lock | 0.000076 |
| Sending data | 3.772659 |
| Waiting for query cache lock | 0.000069 |
| Sending data | 3.346089 |
| Waiting for query cache lock | 0.000245 |
| Sending data | 3.300460 |
| Waiting for query cache lock | 0.000019 |
| Sending data | 3.135361 |
| Waiting for query cache lock | 0.000021 |
| Sending data | 2.909447 |
| Waiting for query cache lock | 0.000039 |
| Sending data | 3.337561 |
| Waiting for query cache lock | 0.000140 |
| Sending data | 3.138180 |
| Waiting for query cache lock | 0.000090 |
| Sending data | 3.060687 |
| Waiting for query cache lock | 0.000085 |
| Sending data | 2.938677 |
| Waiting for query cache lock | 0.000041 |
| Sending data | 2.977974 |
| Waiting for query cache lock | 0.000872 |
| Sending data | 2.918640 |
| Waiting for query cache lock | 0.000036 |
| Sending data | 2.975842 |
| Waiting for query cache lock | 0.000051 |
| Sending data | 2.918988 |
| Waiting for query cache lock | 0.000021 |
| Sending data | 2.943810 |
| Waiting for query cache lock | 0.000061 |
| Sending data | 3.330211 |
| Waiting for query cache lock | 0.000025 |
| Sending data | 3.411236 |
| Waiting for query cache lock | 0.000023 |
| Sending data | 23.339035 |
| end | 0.000807 |
| query end | 0.000023 |
| closing tables | 0.000325 |
| freeing items | 0.001217 |
| logging slow query | 0.000007 |
| logging slow query | 0.000011 |
| cleaning up | 0.000104 |
+------------------------------+-----------+
100 rows in set (0.00 sec)
Tables structures:
CREATE TABLE `attribute` (
`attribute_id` int(11) unsigned NOT NULL AUTO_INCREMENT,
`attribute_type_id` int(11) unsigned DEFAULT NULL,
`attribute_value` int(6) DEFAULT NULL,
`person_id` int(11) unsigned DEFAULT NULL,
PRIMARY KEY (`attribute_id`),
KEY `attribute_type_id` (`attribute_type_id`),
KEY `attribute_value` (`attribute_value`),
KEY `person_id` (`person_id`)
) ENGINE=MyISAM AUTO_INCREMENT=40000001 DEFAULT CHARSET=utf8;
CREATE TABLE `person` (
`person_id` int(11) unsigned NOT NULL AUTO_INCREMENT,
`person_name` text CHARACTER SET latin1,
PRIMARY KEY (`person_id`)
) ENGINE=MyISAM AUTO_INCREMENT=20000001 DEFAULT CHARSET=utf8;
Query had been performed on DigitalOcean virtual server with SSD and 1GB RAM.
I assume there may be problem with database design. Do you have any suggestions to design this situation better please? Or just to adjust the select above?
Best Answer
Pick a few attributes to include in
person. Index them in a few combinations -- use composite indexes, not single-column indexes.That is essentially the only way out of EAV-sucks-at-performance, which is where you are.
Here is more discussion: http://mysql.rjweb.org/doc.php/eav including a suggestion of using JSON instead of the key-value table.