\u573a\u666f<\/strong><\/div>\n
\u73b0\u5728\u8868\u7684\u6570\u636e\u91cf\u6709 800\u4e07\u3002<\/p>\n
\u4e00\u822c\u7684\u4f7f\u7528\u8bed\u53e5\u662f\uff1a<\/p>\n
SELECT * FROM A WHERE c_a IN(955555, 955556, 955557, 955558, 955559);<\/pre>\n
\u4e0a\u9762\u8bed\u53e5\u4f1a\u6267\u884c\u7684\u5f88\u5feb\uff0c\u77e5\u9053\u4f7f\u7528 explain \u7684\u90fd\u660e\u767d\u8fd9\u6837\u4e00\u822c\u90fd\u662f\u4f1a\u4f7f\u7528\u7d22\u5f15\u7684\uff0c\u5e76\u4e14\u662f\u6240\u6709\u8303\u56f4\u626b\u63cf\u3002<\/p>\n
MySQL\u4e0d\u4f1a\u4ece 1 \u5f00\u59cb \u626b\u63cf 800\u4e07\uff0c\u800c\u662f\u4ece555555 \u626b\u63cf\u5230 555559(\u53ea\u8981\u626b\u63cf5\u884c\u6570\u636e)\u3002<\/p>\n
\u5728\u4e00\u822c\u60c5\u51b5\u4e0b\u662f\u6ca1\u6709\u4ec0\u4e48\u95ee\u9898\u7684\u3002\u4f46\u662f\u5982\u679c IN \u91cc\u9762\u7684\u6570\u636e\u662f\u4e0d\u8fde\u7eed\u7684\u5c31\u6709\u5f88\u5927\u95ee\u9898\u4e86\u3002<\/p>\n
\u521b\u5efa\u8868\u7ed3\u6784\u8bed\u53e5<\/strong><\/div>\n
CREATE TABLE t(\r\n id INT unsigned NOT NULL AUTO_INCREMENT,\r\n cid INT unsigned NOT NULL DEFAULT 0,\r\n c1 VARCHAR(50) NOT NULL DEFAULT '',\r\n c2 VARCHAR(50) NOT NULL DEFAULT '',\r\n c3 VARCHAR(50) NOT NULL DEFAULT '',\r\n c4 VARCHAR(50) NOT NULL DEFAULT '',\r\n c5 VARCHAR(50) NOT NULL DEFAULT '',\r\n c6 VARCHAR(50) NOT NULL DEFAULT '',\r\n PRIMARY KEY(id),\r\n INDEX idx$cid(cid)\r\n);\r\n \r\nINSERT INTO t VALUES(\r\n NULL,\r\n FLOOR(RAND() * 1000000),\r\n REPEAT('a', 50),\r\n REPEAT('a', 50),\r\n REPEAT('a', 50),\r\n REPEAT('a', 50),\r\n REPEAT('a', 50),\r\n REPEAT('a', 50)\r\n);\r\n \r\n-- \u91cd\u590d\u6267\u884c\r\nINSERT INTO t\r\nSELECT NULL,\r\n FLOOR(RAND() * 1000000),\r\n c1,\r\n c2,\r\n c3,\r\n c4,\r\n c5,\r\n c6\r\nFROM t;<\/pre>\n
\u4e0b\u9762\u662f\u5177\u4f53\u7684\u5b9e\u9a8c\u8fc7\u7a0b<\/strong><\/div>\n
\n
\u4f7f\u7528IN\u67e5\u8be2\u8fde\u7eed\u7684\u6570<\/li>\n<\/ul>\n
SELECT *\r\nFROM t\r\nWHERE cid IN(955555, 955556, 955557, 955558, 955559);\r\n+---------+--------+-----------------------------------\r\n| id | cid | c1 \r\n+---------+--------+-----------------------------------\r\n| 319330 | 955555 | aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\r\n| 1885293 | 955555 | aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\r\n| ......\r\n| 8733757 | 955559 | aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\r\n| 8796305 | 955559 | aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\r\n+---------+--------+-----------------------------------\r\n41 rows in set (0.15 sec)<\/pre>\n
\n
\u4f7f\u7528IN\u67e5\u8be2\u4e0d\u8fde\u7eed\u7684\u6570<\/li>\n<\/ul>\n
SELECT *\r\nFROM t\r\nWHERE cid IN(1, 5000, 50000, 500000, 955559);\r\n+---------+--------+-----------------------------------\r\n| id | cid | c1 \r\n+---------+--------+-----------------------------------\r\n| 1 | 341702 | 1 | aaaaaaaaaaaaaaaaaaaaaaaaa\r\n| 1 | 1045176 | 1 | aaaaaaaaaaaaaaaaaaaaaaaaa\r\n......\r\n| 955559 | 8733757 | 955559 | aaaaaaaaaaaaaaaaaaaaaaaaa\r\n| 955559 | 8796305 | 955559 | aaaaaaaaaaaaaaaaaaaaaaaaa\r\n+--------+---------+--------+--------------------------\r\n41 rows in set (4.34 sec)<\/pre>\n
\n
\u4f7f\u7528UNION\u4f18\u5316<\/li>\n<\/ul>\n
SELECT *\r\nFROM (\r\n SELECT 1 AS cid UNION ALL\r\n SELECT 5000 UNION ALL\r\n SELECT 50000 UNION ALL\r\n SELECT 500000 UNION ALL\r\n SELECT 955559\r\n) AS tmp, t\r\nWHERE tmp.cid = t.cid;\r\n+---------+--------+-----------------------------------\r\n| id | cid | c1 \r\n+---------+--------+-----------------------------------\r\n| 1 | 341702 | 1 | aaaaaaaaaaaaaaaaaaaaaaaaa\r\n| 1 | 1045176 | 1 | aaaaaaaaaaaaaaaaaaaaaaaaa\r\n......\r\n| 955559 | 8733757 | 955559 | aaaaaaaaaaaaaaaaaaaaaaaaa\r\n| 955559 | 8796305 | 955559 | aaaaaaaaaaaaaaaaaaaaaaaaa\r\n+--------+---------+--------+--------------------------\r\n41 rows in set (0.01 sec)<\/pre>\n
\u4ece\u4e0a\u9762\u53ef\u4ee5\u770b\u51fa\u4e0a\u9762\u4f7f\u7528UNION\u7684\u65b9\u6cd5\u751f\u6210\u4e00\u4e2a\u4e34\u65f6\u8868\u4f5c\u4e3a\u5173\u8054\u7684\u4e3b\u8868\u3002<\/p>\n
\u62d3\u5c55<\/strong><\/div>\n
\u8981\u662fMySQL\u6709\u53ea\u5e26\u7684\u4e00\u4e2a\u884c\u8f6c\u5217\u7684\u51fd\u6570\u90a3\u5c31\u5b8c\u7f8e\u4e86\u3002\u8fd9\u6837\u6211\u4eec\u5c31\u53ef\u4ee5\u4e0d\u7528\u4f7f\u7528UNION\u4e86\u3002<\/p>\n
SELECT 1, 5000, 50000, 500000, 955559;\r\n+---+------+-------+--------+--------+\r\n| 1 | 5000 | 50000 | 500000 | 955559 |\r\n+---+------+-------+--------+--------+\r\n| 1 | 5000 | 50000 | 500000 | 955559 |\r\n+---+------+-------+--------+--------+\r\n1 row in set (0.00 sec)\r\n \r\n\u53d8\u6210\u4ee5\u4e0b\r\nSELECT row_to_col(1, 5000, 50000, 500000, 955559);\r\n+--------+\r\n| id |\r\n+--------+\r\n| 1 |\r\n| 5000 |\r\n| 50000 |\r\n| 500000 |\r\n| 955559 |\r\n+--------+<\/pre>\n
\u8981\u662f\u80fd\u50cf\u4e0a\u9762\u5c31\u592a\u68d2\u4e86\u7b80\u76f4\u3002<\/p>\n
\n
\u539f\u6587\u6765\u81ea\uff1ahttp:\/\/www.ttlsa.com\/mysql\/mysql-sql-performance-let-you-head-big-open\/<\/a><\/p>\n
\u672c\u6587\u5730\u5740\uff1a http:\/\/lrxjmw.cn\/special-optimize-sql.html<\/a>\u7f16\u8f91\uff1a\u6768\u9e4f\u98de\uff0c\u5ba1\u6838\u5458\uff1a\u5cb3\u56fd\u5e05<\/span><\/p>\n<\/blockquote>\n","protected":false},"excerpt":{"rendered":"
\u7531\u4e8e\u5206\u5e93\u5206\u8868\u7684\u539f\u56e0\uff0c\u548c\u5f00\u53d1\u89c4\u5b9a\u4e86\u4e0d\u80fd\u4f7f\u7528 \u8868\u8868JOIN \u8bed\u53e5\u3002\u56e0\u6b64\uff0c\u6211\u4eec\u8981\u5c06 JOIN \u8bed\u53e5\u7684\u8f6c\u5316\u6210\u4f7f\u7528 IN […]<\/p>\n","protected":false},"author":63,"featured_media":31538,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[55],"tags":[],"class_list":["post-45579","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-thread"],"acf":[],"_links":{"self":[{"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/posts\/45579","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/users\/63"}],"replies":[{"embeddable":true,"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/comments?post=45579"}],"version-history":[{"count":4,"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/posts\/45579\/revisions"}],"predecessor-version":[{"id":269362,"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/posts\/45579\/revisions\/269362"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/media\/31538"}],"wp:attachment":[{"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/media?parent=45579"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/categories?post=45579"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/tags?post=45579"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}