{"id":156,"date":"2020-01-22T16:09:13","date_gmt":"2020-01-22T08:09:13","guid":{"rendered":"http:\/\/blog.doublejia.cn\/?p=156"},"modified":"2020-02-10T23:46:56","modified_gmt":"2020-02-10T15:46:56","slug":"%e8%ae%b0%e5%bd%95%e8%87%aa%e5%b7%b1%e8%b8%a9%e8%bf%87%e7%9a%84%e6%af%8f%e4%b8%80%e4%b8%aa%e5%9d%91","status":"publish","type":"post","link":"https:\/\/blog.doublejia.cn\/?p=156","title":{"rendered":"\u8bb0\u5f55\u81ea\u5df1\u8e29\u8fc7\u7684\u6bcf\u4e00\u4e2a\u5751"},"content":{"rendered":"\n<ul><li> \u95ee\u9898\uff1a\u628a Like \"%\" \u653e\u5230\u5e94\u7528\u73af\u5883\u4e2d\u7684\u540e\u679c\u3002 <\/li><\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>CREATE TABLE aa (\n   id int(11) UNSIGNED NOT NULL COMMENT 'PK',\n   aa varchar(50) NOT NULL,\n   bb varchar(255) NOT NULL,\n   c char(128) NOT NULL COMMENT 'details',\n ) ENGINE=InnoDB DEFAULT CHARSET=utf8;\n ALTER TABLE chn_user_v3\n   ADD PRIMARY KEY (id),\n   ADD UNIQUE KEY aa + bb (aa,bb);<\/code><\/pre>\n\n\n\n<p>\u5728\u6700\u65e9\u8bbe\u8ba1\u65f6\uff0c\u5ffd\u7565\u4e86\u4e00\u4e9b\u95ee\u9898\u3002\u5efa\u8868\u65f6\uff0c\u552f\u4e00\u7d22\u5f15\u662f\u4e00\u4e2a\u8054\u5408\u7d22\u5f15\uff0c\u4f46\u7d22\u5f15\u7b2c\u4e00\u5217\u91cc\u7684\u503c\u9700\u6c42\u662f\u6a21\u7cca\u67e5\u8be2\u3002\u5199\u4ee3\u7801\u65f6\uff0c\u7528\u4e86 aa like \"xx%xx\" AND bb = \"xxxx\"\u3002\u5728\u6d4b\u8bd5\u9636\u6bb5\uff0c\u56e0\u4e3a\u6570\u636e\u91cf\u5c11\uff0c\u8bbf\u95ee\u91cf\u4f4e\uff0c\u5e76\u6ca1\u6709\u53d1\u73b0\u95ee\u9898\u3002\u76f4\u5230\u6570\u636e\u5230\u4e86 3M\uff0cQPS20\u5de6\u53f3\u65f6\uff0c\u95ee\u9898\u7206\u53d1\u4e86\u3002<br> \u6267\u884csql\uff0c\u5927\u6982\u89811\u79d2\u3002\u5bfc\u81f4\u5f88\u5feb mysql \u76841000\u4e2a\u8fde\u63a5\u6bcf\u8017\u5c3d -&gt; \u5927\u91cf\u7684too many connections\u7684\u62a5\u9519\u3002<br> \u89e3\u51b3\u95ee\u9898\uff1a<br>     a. \u4ee3\u7801\u53d6\u6d88\u4e86 aa like \"xx%xx\"\u3002\u4f46bb\u5217\u6ca1\u6709\u7d22\u5f15\uff0c\u5e76\u6ca1\u6709\u63d0\u5347\u3002<br>     b. \u4ee3\u7801\u4e2d\u6539\u6210\u4e86 aa like \"xx%\"\u3002\u8fd9\u6837\u53ef\u4ee5\u547d\u4e2d\u7d22\u5f15\uff0c\u6548\u7387\u5f97\u5230\u4e00\u70b9\u70b9\u63d0\u5347\uff0c\u4f46\u8fd8\u662f\u5f88\u6162\u3002\u5e76\u6ca1\u6709\u89e3\u51b3\u6240\u6709\u95ee\u9898\u3002<br>     c. \u5728\u6ca1\u6709\u5176\u5b83\u529e\u6cd5\u7684\u60c5\u51b5\u4e0b\uff0c\u8fd0\u7ef4\u540c\u5b66\u7ed9 bb \u5efa\u4e86\u5355\u72ec\u7684\u7d22\u5f15\u3002\u7136\u540e\u5728\u811a\u672c\u4e2d\uff0c\u53ea\u6309 bb = \"xx\" \u67e5\u627e\u3002\u7136\u540e\u7528\u4ee3\u7801\u533a\u5206 aa \u3002     <br>         PS\uff1a\u8fd9\u91cc\u5176\u5b9e\u4e5f\u6709\u95ee\u9898\uff0c\u56e0\u4e3a\u662f\u7ebf\u4e0a\u73af\u5883\uff0c\u5728\u6267\u884c CREATE INDEX bb ON aa (bb) USING BTREE; \u53ef\u80fd\u4f1a\u9501\u8868\u3002\u8fd0\u7ef4\u7684\u540c\u5b66\u8d39\u4e86\u4e9b\u52b2\u624d\u5efa\u597d\u3002<br> \u53cd\u601d\uff1a<br>     a. \u5728\u5efa\u8868\u7684\u65f6\u5019\uff0c\u4e00\u5b9a\u8981\u60f3\u6e05\u695a\uff0c\u95ee\u6e05\u695a\u3002<br>         I. \u8054\u5408\u7d22\u5f15\uff0c\u4e00\u822c\u8981\u628a\u56fa\u5b9a\u7684\u90e8\u5206\u653e\u5728\u524d\u9762<br>         II. \u53ef\u80fd\u9700\u8981\u62c6\u5f00\u7684\u5b57\u6bb5\uff0c\u5c3d\u65e9\u62c6\u5f00<br>         III. \u4e0d\u8981\u76f8\u4fe1\u4efb\u5408\u4eba\uff0c\u7ed9\u4f60\u8bf4\uff0c\"\u4e0d\u7528\u7ba1\u6027\u80fd\uff0c\u53ea\u8981\u80fd\u8dd1\u901a\"\uff0c\u8fd9\u7c7b\u8bdd\u3002\u56e0\u4e3a\u9047\u5230\u95ee\u9898\u7684\u65f6\u5019\uff0c\u53ea\u80fd\u4f60\u81ea\u5df1\u80fd\u89e3\u51b3\u3002 <\/p>\n\n\n\n<ul><li> \u95ee\u9898 0 == \"x\" \u5728php\u4e2d\u7684\u5e94\u7528 <\/li><\/ul>\n\n\n\n<p> \u5728PHP\u91cc\uff0c\u5728\u4f7f\u7528\"==\"\u5224\u65ad\u65f6\uff0c\u603b\u662f\u628a\u540e\u9762\u7684\u7c7b\u578b\u8f6c\u6210\u548c\u524d\u9762\u4e00\u6837\u518d\u5224\u65ad\u3002<br> \u4e5f\u5c31\u662f\u5982\u679c\u524d\u9762\u662f\u6570\u5b57 0\uff0c\u540e\u9762\u65f6\u5b57\u7b26\u65f6\uff0c\u4f1a\u5148\u628a\u5b57\u7b26\u8f6c\u6210\u6574\u6570\u578b\uff0c\u518d\u5224\u65ad\u3002intval(\"x\") \u662f0\u3002\u6240\u4ee5\u8fd9\u4e2a\u7b49\u5f0f\u4f1a\u8fd4\u56de true\u3002 <\/p>\n\n\n\n<ul><li>Intval \u7684\u53d6\u503c\u8303\u56f4<\/li><\/ul>\n\n\n\n<p>\u67d0\u4e2a\u5e73\u53f0\u7684\u8ba2\u5355\u53f7\uff0c\u53d1\u73b0\u5728\u901a\u8fc7\u6211\u4eec\u7684\u811a\u672c\u5904\u7406\u8fc7\u4e4b\u540e\uff0c\u5168\u90e8\u53d8\u6210\u4e86\u4e00\u6837\u7684\u3002\u770b\u5230\u8ba2\u5355\u53f7\u4e4b\u540e\uff0c\u53d1\u89c9\u662f\u8d85\u8fc7\u4e86php\uff0cintval\u51fd\u6570\u5904\u7406\u7684\u6700\u5927\u8303\u56f4\u3002<br><br>32\u4f4d\uff1a -2147483648  ~  2147483647<br>64\u4f4d\uff1a- 9223372036854775808 ~  9223372036854775807 <br>\u53c2\u8003\uff1a <a href=\"https:\/\/www.php.net\/manual\/zh\/function.intval.php\" target=\"_blank\"  rel=\"nofollow\" >https:\/\/www.php.net\/manual\/zh\/function.intval.php<\/a> <\/p>\n\n\n\n<ul><li>\u7a7a\u683c\u201c \u201d\uff0c\u52a0\u53f7+\u3002\u5728 http \u8bf7\u6c42\u4e2d.......<\/li><\/ul>\n\n\n\n<p>\u5efa\u8bae\u7528 http_build_query() \u6765\u5904\u7406\u53c2\u6570\u3002\u5426\u5219\uff0c\u8fd92\u4e2a\u7b26\u53f7\u771f\u7684\u80fd\u628a\u4f60\u641e\u75af\u6389....\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u95ee\u9898\uff1a\u628a Like &#8220;%&#8221; \u653e\u5230\u5e94\u7528\u73af\u5883\u4e2d\u7684\u540e\u679c\u3002 \u5728\u6700\u65e9\u8bbe\u8ba1\u65f6\uff0c\u5ffd\u7565\u4e86\u4e00\u4e9b\u95ee\u9898\u3002\u5efa\u8868\u65f6\uff0c\u552f\u4e00\u7d22\u5f15\u662f\u4e00\u4e2a\u8054\u5408\u7d22\u5f15\uff0c\u4f46\u7d22\u5f15\u7b2c\u4e00\u5217\u91cc\u7684\u503c\u9700\u6c42\u662f\u6a21\u7cca\u67e5\u8be2\u3002\u5199\u4ee3\u7801\u65f6\uff0c\u7528\u4e86 aa like &#8220;xx%xx&#8221; AND bb = &#8220;xxxx&#8221;\u3002\u5728\u6d4b\u8bd5\u9636\u6bb5\uff0c\u56e0\u4e3a\u6570\u636e\u91cf\u5c11\uff0c\u8bbf\u95ee\u91cf\u4f4e\uff0c\u5e76\u6ca1\u6709\u53d1\u73b0\u95ee\u9898\u3002\u76f4\u5230\u6570\u636e\u5230\u4e86 3M\uff0cQPS20\u5de6\u53f3\u65f6\uff0c\u95ee\u9898\u7206\u53d1\u4e86\u3002 \u6267\u884csql\uff0c\u5927\u6982\u89811\u79d2\u3002\u5bfc\u81f4\u5f88\u5feb mysql \u76841000\u4e2a\u8fde\u63a5\u6bcf\u8017\u5c3d\u2026<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[12],"tags":[17,18],"_links":{"self":[{"href":"https:\/\/blog.doublejia.cn\/index.php?rest_route=\/wp\/v2\/posts\/156"}],"collection":[{"href":"https:\/\/blog.doublejia.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.doublejia.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.doublejia.cn\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.doublejia.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=156"}],"version-history":[{"count":7,"href":"https:\/\/blog.doublejia.cn\/index.php?rest_route=\/wp\/v2\/posts\/156\/revisions"}],"predecessor-version":[{"id":169,"href":"https:\/\/blog.doublejia.cn\/index.php?rest_route=\/wp\/v2\/posts\/156\/revisions\/169"}],"wp:attachment":[{"href":"https:\/\/blog.doublejia.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=156"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.doublejia.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=156"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.doublejia.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=156"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}