MySQL全文索引、联合索引、like查询、json查询速度哪个快
16lz
2021-12-19
查询背景
有一个表tmp_test_course大概有10万条记录,然后有个json字段叫outline,存了一对多关系(保存了多个编码,例如jy1577683381775)
我们需要在这10万条数据中检索特定类型的数据,目标总数据量:2931
条
SELECT COUNT(*) FROM tmp_test_course WHERE `type`=5 AND del=2 AND is_leaf=1
下面分别列出4种方式查询outline字段,给出相应的查询时间和扫描行数
一、like查询
耗时248毫秒
SELECT * FROM tmp_test_course WHERE `type`=5 AND del=2 AND is_leaf=1 AND (outline like '%jy1577683381775%'OR outline like '%jy1577683380808%'OR outline like '%jy1577683379178%'OR outline like '%jy1577683378676%'OR outline like '%jy1577683377617%'OR outline like '%jy1577683376672%'OR outline like '%jy1577683375903%'OR outline like '%jy1578385720787%'OR outline like '%jy1499916986208%'OR outline like '%jy1499917112460%'OR outline like '%jy1499917093400%'OR outline like '%jy1499917335579%'OR outline like '%jy1499917334770%'OR outline like '%jy1499917333339%'OR outline like '%jy1499917331557%'OR outline like '%jy1499917330833%'OR outline like '%jy1499917329615%'OR outline like '%jy1499917328496%'OR outline like '%jy1576922006950%'OR outline like '%jy1499916993558%'OR outline like '%jy1499916992308%'OR outline like '%jy1499917003454%'OR outline like '%jy1499917002952%')
二、json函数查询
json官方函数
耗时196毫秒,速度稍微快了一点
SELECT * FROM tmp_test_course WHERE `type`=5 AND del=2 AND is_leaf=1AND (JSON_SEARCH(outline, 'one', 'jy1577683381775') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1577683380808') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1577683379178') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1577683378676') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1577683377617') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1577683376672') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1577683375903') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1578385720787') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1499916986208') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1499917112460') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1499917093400') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1499917335579') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1499917334770') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1499917333339') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1499917331557') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1499917330833') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1499917329615') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1499917328496') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1576922006950') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1499916993558') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1499916992308') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1499917003454') IS NOT NULL ORJSON_SEARCH(outline, 'one', 'jy1499917002952') IS NOT NULL )
三、联合索引查询
下面为该表建立一个联合索引(本来想建一个type-del-is_leaf-outline的索引,但是outline字段太长限制,所以只加type-del-is_leaf的联合索引
ALTER TABLE tmp_test_course ADD KEY `type-del-is_leaf` (`type`,`del`,`is_leaf`)
EXPLAIN分析结果如下,两者查询扫描的行数都限定在了2931行
四、全文索引查询
因为全文索引只支持CHAR、VARCHAR和TEXT,我们需要把JSON字段定义改一下
ALTER TABLE tmp_test_course MODIFY `outline` VARCHAR(1024) NOT NULL DEFAULT '[]'
ALTER TABLE tmp_test_course ADD FULLTEXT INDEX outline (outline);
SELECT * FROM tmp_test_course WHERE `type`=5 AND del=2 AND is_leaf=1AND MATCH(outline) AGAINST ('jy1577683381775 jy1577683380808 jy1577683379178 jy1577683378676 jy1577683377617 jy1577683376672 jy1577683375903 jy1578385720787 jy1499916986208 jy1499917112460 jy1499917093400 jy1499917335579 jy1499917334770 jy1499917333339 jy1499917331557 jy1499917330833 jy1499917329615 jy1499917328496 jy1576922006950 jy1499916993558 jy1499916992308 jy1499917003454 jy1499917002952')
EXPLAIN分析结果如下,显示只扫描了一行
结论
以下是4种情况的执行结果
全文索引: 11.6ms
联合索引:82.6ms(json)、136ms(like)
json函数查询:196ms
like查询: 248ms
结论:全文索引 > 联合索引 > json函数查询 > like查询
数据量越大,全文索引速度越明显,就10万的量,查询速度大概比直接查询快了20倍左右,如果是百万或千万级别的表,提升差距会更加大,所以有条件还是老老实实用全文索引吧
更多相关文章
- MySQL 什么时候使用INNER JOIN 或 LEFT JOIN
- android感应器Senor
- [android源码下载索引贴】微信+二维码那都不是事......
- android传感器;摇一摇抽签功能
- Android传感器开发基本流程
- android字符串 优化(一)
- android 获取wifi 信号质量
- android触控,先了解MotionEvent
- android 抽屉类slidingdrawer源码解析及运行调试