MySQL利用profile分析慢sql代码实例详解
最近因为一个用了子查询的sql语句查询很慢，严重影响了性能，所以需要进行优化，下面这篇文章主要跟大家介绍了关于MySQL利用profile分析慢sql的相关资料，文中介绍的非常详细，需要的朋友们可以参考借鉴，下面来一起看看吧。
使用profile来分析慢sql
mysql 的 sql 性能分析器主要用途是显示 sql 执行的整个过程中各项资源的使用情况。分析器可以更好的展示出不良 SQL 的性能问题所在。 最近遇到一个查询比较慢的sql语句，用了子查询，大概需要0.8秒左右，这个消耗时间比较长，严重影响了性能，所以需要进行优化。单独查询单表或者子查询记录都很快，下面来看看详细的介绍。
开启profile
mysql> show profiles; -- 查看是否开启 Empty set, 1 warning (0.00 sec) mysql> set profiling=1; -- 开启profile Query OK, 0 rows affected, 1 warning (0.00 sec) mysql> show profiles; Empty set, 1 warning (0.00 sec) mysql>
Salin selepas log masuk
执行查询，方便profile跟踪记录
mysql> SELECT SQL_NO_CACHE -> t1.amount, -> t1.count, -> t1.date , -> (SELECT (CONCAT(t2.APPROVE_ID,'|' ,t2.PATH)) AS RECEIPT FROM TB_BIS_MERCHANT_SETTLEMENT t2 WHERE t2.`MERCHANT_ID` = t1.`MERCHANT_ID` AND t2.`DATE`=t1.DATE AND t2.APPROVE_STATUS=5) AS receipts -> FROM -> TB_BIS_MERCHANT_TURNOVER t1 -> WHERE t1.MERCHANT_ID='64884DE062BC11E682B00017FA000202' -> ORDER BY t1.date DESC -> -> LIMIT 0,100; +-----------+-------+----------+------------------------------------------------------------------------------------------------------------+ | amount | count | date | receipts | +-----------+-------+----------+------------------------------------------------------------------------------------------------------------+ | 15800.00 | 1 | 20170105 | 0DDFD555F93B45BEB0905B1E6DE89D29|http://testxxx.cn/group1/M00/00/49/CvkBIlhu-yqABqmAABYR7dHOmno819.jpg | | 1245.00 | 1 | 20170104 | 0DDFD555F93B45BEB0905B1E6DE89D29|http://testxxx.cn/group1/M00/00/4F/CvkBIVhtpSeAI_YHAADNjq7TPq8244.jpg | | 14766.00 | 4 | 20170103 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/45/CvkBIlhrrf6AQ5uIAAEobJv68FU398.jpg | | 32449.00 | 2 | 20170102 | 0DDFD555F93B45BEB0905B1E6DE89D29|http://testxxx.cn/group1/M00/00/4C/CvkBIVhrDguAfaMIABjKB9uvu04477.jpg | | 37246.00 | 5 | 20170101 | 0DDFD555F93B45BEB0905B1E6DE89D29|http://testxxx.cn/group1/M00/00/4A/CvkBIVhpCnGASEyLAAEu6l9SI0o812.jpg | | 105094.00 | 2 | 20161231 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/49/CvkBIVhnwp-ALIvWAAEAaGPayjg732.jpg | | 88032.00 | 3 | 20161230 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/47/CvkBIVhmaqSAHcEZAAFAyS8Zx8Q067.jpg | | 3845.00 | 1 | 20161229 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/3F/CvkBIlhl206AaS-FAAFMhvX8PYY578.jpg | | 2118.00 | 4 | 20161228 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/3D/CvkBIlhjxhyAMOfhAAD8wUzTUUY855.jpg | | 2980.00 | 1 | 20161227 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/3B/CvkBIlhicfCAFmwgAAE9ULPqEJ4030.jpg | | 1080.00 | 1 | 20161226 | 667E240C44B4469892C261CE9243A8C3|http://testxxx.cn/group1/M00/00/42/CvkBIVhhy6iAMm8tAAFHOT5zBiM875.jpg | | 2980.00 | 1 | 20161225 | 0DDFD555F93B45BEB0905B1E6DE89D29|http://testxxx.cn/group1/M00/00/40/CvkBIVhfzCWAdw2LAAFpDXmwio4327.jpg | | 10201.00 | 1 | 20161224 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/38/CvkBIlhfJfKAIoBiAADqgbF1pBo054.jpg | | 3003.00 | 4 | 20161223 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/3D/CvkBIVhdMHeAQi8cAAGAOQTgxLo422.jpg | | 2698.00 | 1 | 20161222 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/3C/CvkBIVhb2U2AXWRuAAEc4LIr2nc172.jpg | | 990.00 | 1 | 20161221 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/3B/CvkBIVhbM6aAGMQAAAEQ9ptn0FU333.jpg | | 1427.00 | 1 | 20161220 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/31/CvkBIlhZNJqAAsvWAAGuJ6g1pyU541.jpg | | 2465.00 | 1 | 20161219 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/30/CvkBIlhX4_mAfn-SAAEptH1Fyp8152.jpg | | 2360.00 | 1 | 20161218 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/2F/CvkBIlhWl_-AclhbAAGLv79hoh8428.jpg | | 3998.00 | 1 | 20161217 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/35/CvkBIVhVSLGAFct_AAFQRetyWnc285.jpg | | 0.00 | 0 | 20161216 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/2D/CvkBIlhU8g-AXywcAAGn1gdsQQc959.jpg | | 0.00 | 0 | 20161215 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/2A/CvkBIlhSmryAZXITAG-zN3WQv4c789.jpg | | 9900.00 | 1 | 20161214 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/31/CvkBIVhRTrOALwG6AAE_csC3lvk695.jpg | | 4320.00 | 1 | 20161213 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/28/CvkBIlhQrzCAfApEAAFKbHqkH3w634.jpg | | 8760.00 | 2 | 20161212 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/26/CvkBIlhOqjeAO1BdAAGHdajOU2E697.jpg | | 213335.00 | 4 | 20161211 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/2D/CvkBIVhNYQSAfxXgAAHZL9a8Nrs596.jpg | | 47104.00 | 5 | 20161210 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/2C/CvkBIVhMsPSAAnrAAAETxX9fCuw946.jpg | | 6100.00 | 1 | 20161209 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/23/CvkBIlhLfXOAClJVAAFmuoqBI5o264.jpg | | 13515.00 | 2 | 20161208 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/21/CvkBIlhJZ06AbuaNAAGg7Bz3OsA569.jpg | | 26769.00 | 4 | 20161207 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/20/CvkBIlhIGgeAdNxuAAETxX9fCuw408.jpg | | 0.00 | 0 | 20161206 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/1E/CvkBIlhGxAuAfQr8AAFatVZ2sFk337.jpg | | 0.00 | 0 | 20161205 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/1D/CvkBIlhGKy-AU9guAAGm4jFhmoU601.jpg | | 20000.00 | 3 | 20161204 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/23/CvkBIVhEIDGAMPuIAAH6chL6Wo8684.jpg | | 20275.00 | 4 | 20161203 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/21/CvkBIVhCyrSAE-uGAAGf0CWFbZM991.jpg | | 3988.00 | 1 | 20161202 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/19/CvkBIlhCI7mAUN_9AAIsSLMhcns351.jpg | | 4460.00 | 1 | 20161201 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/17/CvkBIlhAKwmACroNAAGpJUqVqIA247.jpg | | 10498.00 | 2 | 20161130 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/16/CvkBIlg-3euAbsd5AAGr-r7GCH0254.jpg | | 11080.00 | 2 | 20161129 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/1C/CvkBIVg9i6WAD4Z0AAHLB1yISaQ864.jpg | | 6100.00 | 1 | 20161128 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/1B/CvkBIVg8OHGABTZOAAG1ZWoLoXY932.jpg | | 5580.00 | 1 | 20161127 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/19/CvkBIVg65aKAcRWWAAFnaqaodKs660.jpg | | 32630.00 | 2 | 20161126 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/18/CvkBIVg5kveALns0AAHLB1yISaQ850.jpg | | 9800.00 | 1 | 20161125 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/17/CvkBIVg4Qg2AMqoNAAH--He3hsg726.jpg | | 32500.00 | 2 | 20161124 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/16/CvkBIVg27_OAAV5OAAE8vRiZWHs684.jpg | | 2700.00 | 1 | 20161123 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/0E/CvkBIlg2T4OAL3t5AAFsAWaUI98731.jpg | | 4580.00 | 1 | 20161122 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/14/CvkBIVg0-UeAFDr_AAIBY_LNIxs656.jpg | | 14120.00 | 1 | 20161121 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/0B/CvkBIlgy_EeAaPdBAAHeyO5nxeo952.jpg | | 41510.00 | 2 | 20161120 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/12/CvkBIVgyYRKAZKi3AAGEp_IGjVM389.jpg | | 7800.00 | 2 | 20161118 | C91D5E7905BA44C8A14045C9C228157F|http://testxxx.cn/group1/M00/00/09/CvkBIlgw_viAFHiPAAH0MZwoiCE530.jpg | +-----------+-------+----------+------------------------------------------------------------------------------------------------------------+ 48 rows in set (0.75 sec) mysql>
Salin selepas log masuk
查看当前的profile记录，主要获得Query_ID值
mysql> show profiles; +----------+------------+------------------------------------------------------------------ -------------------------------------------------------------------------------------------------------------------------------- ------------------------------------------------------------------------------------------------------------+ | Query_ID | Duration | Query | +----------+------------+------------------------------------------------------------------------------------- ------------------------------------------------------------------------------------------------------------------ -------------------------------------------------------------------------------------------------------+ | 1 | 0.00009250 | show warning | | 2 | 0.00013125 | show warnings | | 3 | 0.00014375 | set profiling=1 | | 4 | 0.75458525 | SELECT SQL_NO_CACHE t1.amount, t1.count, t1.date , (SELECT (CONCAT(t2.APPROVE_ID,'|' ,t2.PATH)) AS RECEIPT FROM TB_BIS_MERCHANT_SETTLEMENT t2 WHERE t2.`MERCHANT_ID` = t1.`MERCHANT_ID` AND t2.`DATE`=t1.DATE AND t2.APPROVE_STATUS=5) AS r | +----------+------------+---------------------------------------------------------------------------------------------------------------------- ------------------------------------------------------------------------------------------------------------------------------------------------- ---------------------------------------+ 4 rows in set, 1 warning (0.00 sec) mysql>
Salin selepas log masuk
查看刚才执行的Query_ID为4的跟踪记录
mysql> show profile for query 4; +--------------------+----------+ | Status | Duration | +--------------------+----------+ | executing | 0.000017 | | Sending data | 0.018048 | | executing | 0.000028 | | Sending data | 0.018125 | | executing | 0.000022 | | Sending data | 0.015749 | | executing | 0.000017 | | Sending data | 0.015633 | | executing | 0.000017 | | Sending data | 0.015382 | | executing | 0.000015 | | Sending data | 0.015707 | | executing | 0.000023 | | Sending data | 0.015890 | | executing | 0.000022 | | Sending data | 0.015908 | | executing | 0.000017 | | Sending data | 0.015761 | | executing | 0.000022 | | Sending data | 0.015542 | | executing | 0.000014 | | Sending data | 0.015561 | | executing | 0.000016 | | Sending data | 0.015546 | | executing | 0.000037 | | Sending data | 0.015555 | | executing | 0.000015 | | Sending data | 0.015779 | | executing | 0.000026 | | Sending data | 0.015815 | | executing | 0.000015 | | Sending data | 0.015468 | | executing | 0.000015 | | Sending data | 0.015457 | | executing | 0.000015 | | Sending data | 0.015457 | | executing | 0.000014 | | Sending data | 0.015500 | | executing | 0.000014 | | Sending data | 0.015557 | | executing | 0.000015 | | Sending data | 0.015537 | | executing | 0.000014 | | Sending data | 0.015395 | | executing | 0.000021 | | Sending data | 0.015416 | | executing | 0.000014 | | Sending data | 0.015416 | | executing | 0.000014 | | Sending data | 0.015399 | | executing | 0.000023 | | Sending data | 0.015407 | | executing | 0.000014 | | Sending data | 0.015585 | | executing | 0.000014 | | Sending data | 0.015385 | | executing | 0.000014 | | Sending data | 0.015412 | | executing | 0.000014 | | Sending data | 0.015408 | | executing | 0.000014 | | Sending data | 0.015753 | | executing | 0.000014 | | Sending data | 0.015376 | | executing | 0.000014 | | Sending data | 0.015416 | | executing | 0.000019 | | Sending data | 0.015368 | | executing | 0.000014 | | Sending data | 0.015481 | | executing | 0.000015 | | Sending data | 0.015619 | | executing | 0.000015 | | Sending data | 0.015662 | | executing | 0.000016 | | Sending data | 0.015574 | | executing | 0.000015 | | Sending data | 0.015566 | | executing | 0.000015 | | Sending data | 0.015488 | | executing | 0.000013 | | Sending data | 0.015493 | | executing | 0.000015 | | Sending data | 0.015386 | | executing | 0.000015 | | Sending data | 0.015485 | | executing | 0.000018 | | Sending data | 0.015760 | | executing | 0.000014 | | Sending data | 0.015386 | | executing | 0.000015 | | Sending data | 0.015418 | | executing | 0.000014 | | Sending data | 0.015458 | | end | 0.000016 | | query end | 0.000019 | | closing tables | 0.000018 | | freeing items | 0.000825 | | logging slow query | 0.000067 | | cleaning up | 0.000025 | +--------------------+----------+ 100 rows in set, 1 warning (0.00 sec) mysql>
Salin selepas log masuk
根据分析结果可以看到，有大量的Sending data消耗，而且是持续不断的，这样的可以判断为子查询导致的，所以在这个case里面，子查询不适合用，效率太低。 那该用什么来避免呢？
用group by + left join 改写
mysql> SELECT SQL_NO_CACHE DISTINCT -> t1.amount, -> t1.count, -> t1.date, GROUP_CONCAT(CONCAT(t2.APPROVE_ID,'|' ,t2.PATH)) AS RECEIPT -> FROM -> TB_BIS_MERCHANT_TURNOVER t1 LEFT JOIN TB_BIS_MERCHANT_SETTLEMENT t2 ON t2. `MERCHANT_ID` = t1.`MERCHANT_ID` AND t2.`DATE`=t1.DATE AND t2.APPROVE_STATUS=5 -> WHERE t1.MERCHANT_ID='64884DE062BC11E682B00017FA000202' -> GROUP BY t1.amount, -> t1.count, -> t1.date -> ORDER BY t1.date DESC -> -> LIMIT 0,100; +-----------+-------+----------+------------------------------------------------------------------------------------------------------------+ | amount | count | date | RECEIPT | +-----------+-------+----------+------------------------------------------------------------------------------------------------------------+ | 15800.00 | 1 | 20170105 | 0DDFD555F93B45BEB0905B1E6DE89D29|http://testxxx.cn/group1/M00/00/49/CvkBIlhu-yqABqmAABYR7dHOmno819.jpg | | 1245.00 | 1 | 20170104 | 0DDFD555F93B45BEB0905B1E6DE89D29|http://testxxx.cn/group1/M00/00/4F/CvkBIVhtpSeAI_YHAADNjq7TPq8244.jpg | | 14766.00 | 4 | 20170103 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/45/CvkBIlhrrf6AQ5uIAAEobJv68FU398.jpg | | 32449.00 | 2 | 20170102 | 0DDFD555F93B45BEB0905B1E6DE89D29|http://testxxx.cn/group1/M00/00/4C/CvkBIVhrDguAfaMIABjKB9uvu04477.jpg | | 37246.00 | 5 | 20170101 | 0DDFD555F93B45BEB0905B1E6DE89D29|http://testxxx.cn/group1/M00/00/4A/CvkBIVhpCnGASEyLAAEu6l9SI0o812.jpg | | 105094.00 | 2 | 20161231 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/49/CvkBIVhnwp-ALIvWAAEAaGPayjg732.jpg | | 88032.00 | 3 | 20161230 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/47/CvkBIVhmaqSAHcEZAAFAyS8Zx8Q067.jpg | | 3845.00 | 1 | 20161229 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/3F/CvkBIlhl206AaS-FAAFMhvX8PYY578.jpg | | 2118.00 | 4 | 20161228 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/3D/CvkBIlhjxhyAMOfhAAD8wUzTUUY855.jpg | | 2980.00 | 1 | 20161227 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/3B/CvkBIlhicfCAFmwgAAE9ULPqEJ4030.jpg | | 1080.00 | 1 | 20161226 | 667E240C44B4469892C261CE9243A8C3|http://testxxx.cn/group1/M00/00/42/CvkBIVhhy6iAMm8tAAFHOT5zBiM875.jpg | | 2980.00 | 1 | 20161225 | 0DDFD555F93B45BEB0905B1E6DE89D29|http://testxxx.cn/group1/M00/00/40/CvkBIVhfzCWAdw2LAAFpDXmwio4327.jpg | | 10201.00 | 1 | 20161224 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/38/CvkBIlhfJfKAIoBiAADqgbF1pBo054.jpg | | 3003.00 | 4 | 20161223 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/3D/CvkBIVhdMHeAQi8cAAGAOQTgxLo422.jpg | | 2698.00 | 1 | 20161222 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/3C/CvkBIVhb2U2AXWRuAAEc4LIr2nc172.jpg | | 990.00 | 1 | 20161221 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/3B/CvkBIVhbM6aAGMQAAAEQ9ptn0FU333.jpg | | 1427.00 | 1 | 20161220 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/31/CvkBIlhZNJqAAsvWAAGuJ6g1pyU541.jpg | | 2465.00 | 1 | 20161219 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/30/CvkBIlhX4_mAfn-SAAEptH1Fyp8152.jpg | | 2360.00 | 1 | 20161218 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/2F/CvkBIlhWl_-AclhbAAGLv79hoh8428.jpg | | 3998.00 | 1 | 20161217 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/35/CvkBIVhVSLGAFct_AAFQRetyWnc285.jpg | | 0.00 | 0 | 20161216 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/2D/CvkBIlhU8g-AXywcAAGn1gdsQQc959.jpg | | 0.00 | 0 | 20161215 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/2A/CvkBIlhSmryAZXITAG-zN3WQv4c789.jpg | | 9900.00 | 1 | 20161214 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/31/CvkBIVhRTrOALwG6AAE_csC3lvk695.jpg | | 4320.00 | 1 | 20161213 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/28/CvkBIlhQrzCAfApEAAFKbHqkH3w634.jpg | | 8760.00 | 2 | 20161212 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/26/CvkBIlhOqjeAO1BdAAGHdajOU2E697.jpg | | 213335.00 | 4 | 20161211 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/2D/CvkBIVhNYQSAfxXgAAHZL9a8Nrs596.jpg | | 47104.00 | 5 | 20161210 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/2C/CvkBIVhMsPSAAnrAAAETxX9fCuw946.jpg | | 6100.00 | 1 | 20161209 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/23/CvkBIlhLfXOAClJVAAFmuoqBI5o264.jpg | | 13515.00 | 2 | 20161208 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/21/CvkBIlhJZ06AbuaNAAGg7Bz3OsA569.jpg | | 26769.00 | 4 | 20161207 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/20/CvkBIlhIGgeAdNxuAAETxX9fCuw408.jpg | | 0.00 | 0 | 20161206 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/1E/CvkBIlhGxAuAfQr8AAFatVZ2sFk337.jpg | | 0.00 | 0 | 20161205 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/1D/CvkBIlhGKy-AU9guAAGm4jFhmoU601.jpg | | 20000.00 | 3 | 20161204 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/23/CvkBIVhEIDGAMPuIAAH6chL6Wo8684.jpg | | 20275.00 | 4 | 20161203 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/21/CvkBIVhCyrSAE-uGAAGf0CWFbZM991.jpg | | 3988.00 | 1 | 20161202 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/19/CvkBIlhCI7mAUN_9AAIsSLMhcns351.jpg | | 4460.00 | 1 | 20161201 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/17/CvkBIlhAKwmACroNAAGpJUqVqIA247.jpg | | 10498.00 | 2 | 20161130 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/16/CvkBIlg-3euAbsd5AAGr-r7GCH0254.jpg | | 11080.00 | 2 | 20161129 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/1C/CvkBIVg9i6WAD4Z0AAHLB1yISaQ864.jpg | | 6100.00 | 1 | 20161128 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/1B/CvkBIVg8OHGABTZOAAG1ZWoLoXY932.jpg | | 5580.00 | 1 | 20161127 | 98FDB31FE4B04C21BC7EBE8A22981DA0|http://testxxx.cn/group1/M00/00/19/CvkBIVg65aKAcRWWAAFnaqaodKs660.jpg | | 32630.00 | 2 | 20161126 | 2154FDCDA51A4257811F1EA886AACD14|http://testxxx.cn/group1/M00/00/18/CvkBIVg5kveALns0AAHLB1yISaQ850.jpg | | 9800.00 | 1 | 20161125 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/17/CvkBIVg4Qg2AMqoNAAH--He3hsg726.jpg | | 32500.00 | 2 | 20161124 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/16/CvkBIVg27_OAAV5OAAE8vRiZWHs684.jpg | | 2700.00 | 1 | 20161123 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/0E/CvkBIlg2T4OAL3t5AAFsAWaUI98731.jpg | | 4580.00 | 1 | 20161122 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/14/CvkBIVg0-UeAFDr_AAIBY_LNIxs656.jpg | | 14120.00 | 1 | 20161121 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/0B/CvkBIlgy_EeAaPdBAAHeyO5nxeo952.jpg | | 41510.00 | 2 | 20161120 | EC481757CFDB445092D16D6B616350C8|http://testxxx.cn/group1/M00/00/12/CvkBIVgyYRKAZKi3AAGEp_IGjVM389.jpg | | 7800.00 | 2 | 20161118 | C91D5E7905BA44C8A14045C9C228157F|http://testxxx.cn/group1/M00/00/09/CvkBIlgw_viAFHiPAAH0MZwoiCE530.jpg | +-----------+-------+----------+------------------------------------------------------------------------------------------------------------+ 48 rows in set (0.15 sec) mysql>
Salin selepas log masuk
可以看到，执行时间变成了0.15秒，提升了5倍的效率。再看profile的跟踪分析。
mysql> show profile for query 8; +-------------------------------+----------+ | Status | Duration | +-------------------------------+----------+ | starting | 0.000125 | | checking permissions | 0.000015 | | checking permissions | 0.000014 | | Opening tables | 0.000029 | | init | 0.000055 | | System lock | 0.000020 | | Waiting for query cache lock | 0.000013 | | System lock | 0.000050 | | optimizing | 0.000023 | | statistics | 0.000087 | | preparing | 0.000066 | | Creating tmp table | 0.000062 | | Creating tmp table | 0.000028 | | Sorting result | 0.000016 | | executing | 0.000012 | | Sending data | 0.148283 | | Creating sort index | 0.000342 | | Creating sort index | 0.000223 | | end | 0.000015 | | query end | 0.000046 | | removing tmp table | 0.000017 | | query end | 0.000012 | | removing tmp table | 0.000062 | | query end | 0.000015 | | closing tables | 0.000017 | | freeing items | 0.000019 | | removing tmp table | 0.000025 | | freeing items | 0.000016 | | Waiting for query cache lock | 0.000012 | | freeing items | 0.000915 | | Waiting for query cache lock | 0.000015 | | freeing items | 0.000011 | | storing result in query cache | 0.000013 | | cleaning up | 0.000024 | +-------------------------------+----------+ 34 rows in set, 1 warning (0.00 sec) mysql>
Salin selepas log masuk
可以看到，只有一次| Sending data | 0.148283 |的消耗，所以效率提升很快。
扩展部分
SELECT NAME, VALUE FROM v $ parameter WHERE NAME IN ( 'pga_aggregate_target', 'sga_target' ) UNION SELECT 'maximum PGA allocated' AS NAME, TO_CHAR (VALUE) AS VALUE FROM v $ pgastat WHERE NAME = 'maximum PGA allocated' ;
Salin selepas log masuk
-- insert data insert into t1 select 1,'a' from db1.t2; call db1.proc_get_fints
Salin selepas log masuk
总结
Atas ialah kandungan terperinci MySQL利用profile分析慢sql代码实例详解. Untuk maklumat lanjut, sila ikut artikel berkaitan lain di laman web China PHP!
Kenyataan Laman Web ini
Kandungan artikel ini disumbangkan secara sukarela oleh netizen, dan hak cipta adalah milik pengarang asal. Laman web ini tidak memikul tanggungjawab undang-undang yang sepadan. Jika anda menemui sebarang kandungan yang disyaki plagiarisme atau pelanggaran, sila hubungi admin@php.cn
Alat AI Hot
Undresser.AI Undress
Apl berkuasa AI untuk mencipta foto bogel yang realistik
AI Clothes Remover
Alat AI dalam talian untuk mengeluarkan pakaian daripada foto.
Undress AI Tool
Gambar buka pakaian secara percuma
Clothoff.io
Penyingkiran pakaian AI
AI Hentai Generator
Menjana ai hentai secara percuma.
Artikel Panas
R.E.P.O. Kristal tenaga dijelaskan dan apa yang mereka lakukan (kristal kuning)
4 minggu yang lalu
By 尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Tetapan grafik terbaik
4 minggu yang lalu
By 尊渡假赌尊渡假赌尊渡假赌
Assassin's Creed Shadows: Penyelesaian Riddle Seashell
2 minggu yang lalu
By DDD
R.E.P.O. Cara Memperbaiki Audio Jika anda tidak dapat mendengar sesiapa
4 minggu yang lalu
By 尊渡假赌尊渡假赌尊渡假赌
WWE 2K25: Cara Membuka Segala -galanya Di Myrise
1 bulan yang lalu
By 尊渡假赌尊渡假赌尊渡假赌
Alat panas
Notepad++7.3.1
Editor kod yang mudah digunakan dan percuma
SublimeText3 versi Cina
Versi Cina, sangat mudah digunakan
Hantar Studio 13.0.1
Persekitaran pembangunan bersepadu PHP yang berkuasa
Dreamweaver CS6
Alat pembangunan web visual
SublimeText3 versi Mac
Perisian penyuntingan kod peringkat Tuhan (SublimeText3)
Topik panas
Tutorial CakePHP
1378
52
1378
52
MySQL: Kemudahan Pengurusan Data untuk Pemula
Apr 09, 2025 am 12:07 AM
MySQL sesuai untuk pemula kerana mudah dipasang, kuat dan mudah untuk menguruskan data. 1. Pemasangan dan konfigurasi mudah, sesuai untuk pelbagai sistem operasi. 2. Menyokong operasi asas seperti membuat pangkalan data dan jadual, memasukkan, menanyakan, mengemas kini dan memadam data. 3. Menyediakan fungsi lanjutan seperti menyertai operasi dan subqueries. 4. Prestasi boleh ditingkatkan melalui pengindeksan, pengoptimuman pertanyaan dan pembahagian jadual. 5. Sokongan sokongan, pemulihan dan langkah keselamatan untuk memastikan keselamatan data dan konsistensi.
Cara membuka phpmyadmin
Apr 10, 2025 pm 10:51 PM
Anda boleh membuka phpmyadmin melalui langkah -langkah berikut: 1. Log masuk ke panel kawalan laman web; 2. Cari dan klik ikon phpmyadmin; 3. Masukkan kelayakan MySQL; 4. Klik "Login".
MySQL dan SQL: Kemahiran Penting untuk Pemaju
Apr 10, 2025 am 09:30 AM
MySQL dan SQL adalah kemahiran penting untuk pemaju. 1.MYSQL adalah sistem pengurusan pangkalan data sumber terbuka, dan SQL adalah bahasa standard yang digunakan untuk mengurus dan mengendalikan pangkalan data. 2.MYSQL menyokong pelbagai enjin penyimpanan melalui penyimpanan data yang cekap dan fungsi pengambilan semula, dan SQL melengkapkan operasi data yang kompleks melalui pernyataan mudah. 3. Contoh penggunaan termasuk pertanyaan asas dan pertanyaan lanjutan, seperti penapisan dan penyortiran mengikut keadaan. 4. Kesilapan umum termasuk kesilapan sintaks dan isu -isu prestasi, yang boleh dioptimumkan dengan memeriksa penyataan SQL dan menggunakan perintah menjelaskan. 5. Teknik pengoptimuman prestasi termasuk menggunakan indeks, mengelakkan pengimbasan jadual penuh, mengoptimumkan operasi menyertai dan meningkatkan kebolehbacaan kod.
Cara Membuat Premium Navicat
Apr 09, 2025 am 07:09 AM
Buat pangkalan data menggunakan Navicat Premium: Sambungkan ke pelayan pangkalan data dan masukkan parameter sambungan. Klik kanan pada pelayan dan pilih Buat Pangkalan Data. Masukkan nama pangkalan data baru dan set aksara yang ditentukan dan pengumpulan. Sambung ke pangkalan data baru dan buat jadual dalam penyemak imbas objek. Klik kanan di atas meja dan pilih masukkan data untuk memasukkan data.
Mysql: Konsep mudah untuk pembelajaran mudah
Apr 10, 2025 am 09:29 AM
MySQL adalah sistem pengurusan pangkalan data sumber terbuka. 1) Buat Pangkalan Data dan Jadual: Gunakan perintah Createdatabase dan Createtable. 2) Operasi Asas: Masukkan, Kemas kini, Padam dan Pilih. 3) Operasi lanjutan: Sertai, subquery dan pemprosesan transaksi. 4) Kemahiran Debugging: Semak sintaks, jenis data dan keizinan. 5) Cadangan Pengoptimuman: Gunakan indeks, elakkan pilih* dan gunakan transaksi.
Cara Membuat Sambungan Baru ke MySQL di Navicat
Apr 09, 2025 am 07:21 AM
Anda boleh membuat sambungan MySQL baru di Navicat dengan mengikuti langkah -langkah: Buka aplikasi dan pilih Sambungan Baru (Ctrl N). Pilih "MySQL" sebagai jenis sambungan. Masukkan nama host/alamat IP, port, nama pengguna, dan kata laluan. (Pilihan) Konfigurasikan pilihan lanjutan. Simpan sambungan dan masukkan nama sambungan.
Cara Menggunakan AWS Glue Crawler dengan Amazon Athena
Apr 09, 2025 pm 03:09 PM
Sebagai profesional data, anda perlu memproses sejumlah besar data dari pelbagai sumber. Ini boleh menimbulkan cabaran kepada pengurusan data dan analisis. Nasib baik, dua perkhidmatan AWS dapat membantu: AWS Glue dan Amazon Athena.
Cara Melaksanakan SQL di Navicat
Apr 08, 2025 pm 11:42 PM
Langkah -langkah untuk melaksanakan SQL di Navicat: Sambungkan ke pangkalan data. Buat tetingkap editor SQL. Tulis pertanyaan SQL atau skrip. Klik butang Run untuk melaksanakan pertanyaan atau skrip. Lihat hasilnya (jika pertanyaan dilaksanakan).
