MySQL全文索引、联合索引、like查询、json查询速度大比拼 _MySQL

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

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我们在限定为上面类型的同时，还得包含下面任意一个编码（也就是OR查询）

jy1577683381775jy1577683380808jy1577683379178jy1577683378676jy1577683377617jy1577683376672jy1577683375903jy1578385720787jy1499916986208jy1499917112460jy1499917093400jy1499917335579jy1499917334770jy1499917333339jy1499917331557jy1499917330833jy1499917329615jy1499917328496jy1576922006950jy1499916993558jy1499916992308jy1499917003454jy1499917002952

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%')

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EXPLAIN分析结果如下，全表扫描

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二、json函数查询使用函数JSON_SEARCH，更多函数请查看MySQL官方文档
可以看到，查询耗时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)

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EXPLAIN分析结果如下，还是全表扫描

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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`)加入索引后再执行like和json查询，明显提速。like执行用了136毫秒，json查询用了82.6毫秒，由此可见针对json类型使用json函数查询比like快