{"id":312746,"date":"2024-05-20T22:46:57","date_gmt":"2024-05-20T14:46:57","guid":{"rendered":"https:\/\/docs.pingcode.com\/ask\/ask-ask\/312746.html"},"modified":"2024-05-20T22:47:28","modified_gmt":"2024-05-20T14:47:28","slug":"sql-%e4%b8%ad%e6%a8%a1%e7%b3%8a%e6%9f%a5%e8%af%a2%e6%80%8e%e4%b9%88%e5%86%99-%e5%b8%b8%e7%94%a8%e7%9a%84%e8%81%9a%e5%90%88%e5%87%bd%e6%95%b0%e6%9c%89%e5%93%aa%e4%ba%9b","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/312746.html","title":{"rendered":"Sql \u4e2d\u6a21\u7cca\u67e5\u8be2\u600e\u4e48\u5199 \u5e38\u7528\u7684\u805a\u5408\u51fd\u6570\u6709\u54ea\u4e9b"},"content":{"rendered":"

\"Sql<\/p>\n

SQL\u4e2d\u7684\u6a21\u728a\u67e5\u8be2\u4e3b\u8981\u901a\u8fc7LIKE<\/code>\u5173\u952e\u5b57\u5b9e\u73b0\uff0c\u800c\u5e38\u7528\u7684SQL\u805a\u5408\u51fd\u6570\u5305\u62ecCOUNT()<\/code>\u3001SUM()<\/code>\u3001AVG()<\/code>\u3001MAX()<\/code>\u4e0eMIN()<\/code>\u3002\u8fd9\u4e9b\u805a\u5408\u51fd\u6570\u5728\u5904\u7406\u6570\u636e\u5e93\u67e5\u8be2\u65f6\u8d77\u7740\u81f3\u5173\u91cd\u8981\u7684\u4f5c\u7528\uff0c\u5c24\u5176\u5728\u5bf9\u5927\u91cf\u6570\u636e\u8fdb\u884c\u603b\u7ed3\u3001\u5206\u6790\u65f6\u66f4\u663e\u5176\u4ef7\u503c\u3002\u4f8b\u5982\uff0cAVG()<\/code>\u51fd\u6570\u53ef\u4ee5\u7528\u6765\u8ba1\u7b97\u67d0\u5217\u6240\u6709\u975eNULL\u503c\u7684\u5e73\u5747\u503c\uff0c\u8fd9\u5728\u5206\u6790\u6570\u636e\u5747\u8861\u5ea6\u3001\u9884\u6d4b\u8d8b\u52bf\u65f6\u975e\u5e38\u6709\u7528\u3002<\/p>\n<\/p>\n

\u4e00\u3001\u6a21\u7cca\u67e5\u8be2\u7684\u5199\u6cd5<\/h3>\n<\/p>\n

\u6a21\u7cca\u67e5\u8be2\u5728\u6570\u636e\u5e93\u64cd\u4f5c\u4e2d\u6781\u4e3a\u5e38\u89c1\uff0c\u5b83\u5141\u8bb8\u7528\u6237\u6839\u636e\u4e0d\u5b8c\u5168\u5339\u914d\u7684\u6761\u4ef6\u6765\u67e5\u8be2\u6570\u636e\u3002\u5728SQL\u4e2d\uff0c\u8fd9\u4e3b\u8981\u901a\u8fc7\u4f7f\u7528LIKE<\/code>\u5173\u952e\u8bcd\u5b9e\u73b0\uff0c\u5b83\u652f\u6301\u4e24\u79cd\u901a\u914d\u7b26\uff1a%<\/code>\u548c_<\/code>\u3002<\/p>\n<\/p>\n

    \n
  1. \n

    \u767e\u5206\u53f7\uff08%\uff09\u662f\u6700\u5e38\u7528\u7684\u901a\u914d\u7b26\uff0c\u4ee3\u8868\u4efb\u610f\u5b57\u7b26\u51fa\u73b0\u4efb\u610f\u6b21\u6570\u3002\u4f8b\u5982\uff0cSELECT * FROM users WHERE name LIKE 'a%'<\/code>\u5c06\u4f1a\u5339\u914d\u6240\u6709\u4ee5\u5b57\u6bcd"a"\u5f00\u5934\u7684\u540d\u79f0\u3002<\/p>\n<\/p>\n<\/li>\n

  2. \n

    \u4e0b\u5212\u7ebf\uff08_\uff09\u901a\u914d\u7b26\u4ee3\u8868\u4efb\u610f\u5355\u4e2a\u5b57\u7b26\u3002\u4f8b\u5982\uff0cSELECT * FROM users WHERE name LIKE 'a___a'<\/code>\u5c06\u4f1a\u5339\u914d\u6240\u6709\u4ee5"a"\u5f00\u5934\u548c\u7ed3\u5c3e\u3001\u5e76\u4e14\u603b\u957f\u5ea6\u4e3a5\u4e2a\u5b57\u7b26\u7684\u540d\u79f0\u3002<\/p>\n<\/p>\n<\/li>\n<\/ol>\n

    \u4e8c\u3001\u5e38\u7528\u805a\u5408\u51fd\u6570\u7684\u5e94\u7528<\/h3>\n<\/p>\n

    SQL\u805a\u5408\u51fd\u6570\u5bf9\u4e8e\u6570\u636e\u5206\u6790\u81f3\u5173\u91cd\u8981\uff0c\u5b83\u4eec\u5141\u8bb8\u5bf9\u4e00\u7cfb\u5217\u503c\u6267\u884c\u8ba1\u7b97\uff0c\u5e76\u8fd4\u56de\u5355\u4e00\u503c\u3002<\/p>\n<\/p>\n

      \n
    1. \n

      COUNT()\u51fd\u6570<\/strong><\/p>\n<\/p>\n

      COUNT()<\/code>\u7528\u4e8e\u8ba1\u7b97\u8868\u4e2d\u884c\u7684\u6570\u76ee\uff0c\u6216\u8005\u6ee1\u8db3\u7279\u5b9a\u6761\u4ef6\u7684\u884c\u7684\u6570\u76ee\u3002\u4f8b\u5982\uff0cSELECT COUNT(*) FROM orders<\/code>\u7528\u4e8e\u8ba1\u7b97\u8ba2\u5355\u8868\u4e2d\u7684\u8ba2\u5355\u603b\u6570\u3002<\/p>\n<\/p>\n<\/li>\n

    2. \n

      SUM()\u51fd\u6570<\/strong><\/p>\n<\/p>\n

      SUM()<\/code>\u51fd\u6570\u7528\u4e8e\u8ba1\u7b97\u67d0\u5217\u6240\u6709\u975eNULL\u503c\u7684\u603b\u548c\u3002\u4f8b\u5982\uff0cSELECT SUM(amount) FROM transactions<\/code>\u5c06\u4f1a\u8fd4\u56de\u4ea4\u6613\u989d\u7684\u603b\u548c\u3002<\/p>\n<\/p>\n<\/li>\n

    3. \n

      AVG()\u51fd\u6570<\/strong><\/p>\n<\/p>\n

      AVG()<\/code>\u51fd\u6570\u8ba1\u7b97\u67d0\u5217\u6240\u6709\u975eNULL\u503c\u7684\u5e73\u5747\u503c\u3002\u4f8b\u5982\uff0cSELECT AVG(price) FROM products<\/code>\u53ef\u4ee5\u5e2e\u52a9\u5206\u6790\u4ea7\u54c1\u5e73\u5747\u5b9a\u4ef7\u3002<\/p>\n<\/p>\n<\/li>\n

    4. \n

      MAX()\u4e0eMIN()\u51fd\u6570<\/strong><\/p>\n<\/p>\n

      MAX()<\/code>\u548cMIN()<\/code>\u51fd\u6570\u5206\u522b\u7528\u4e8e\u67e5\u627e\u67d0\u5217\u7684\u6700\u5927\u503c\u548c\u6700\u5c0f\u503c\u3002\u4f8b\u5982\uff0cSELECT MAX(salary) FROM employees<\/code>\u53ef\u4ee5\u627e\u51fa\u5458\u5de5\u4e2d\u7684\u6700\u9ad8\u85aa\u6c34\uff0c\u800cSELECT MIN(salary) FROM employees<\/code>\u7528\u4e8e\u67e5\u8be2\u6700\u4f4e\u85aa\u6c34\u3002<\/p>\n<\/p>\n<\/li>\n<\/ol>\n

      \u4e09\u3001\u590d\u5408\u805a\u5408\u51fd\u6570\u7684\u4f7f\u7528<\/h3>\n<\/p>\n

      \u5728\u5b9e\u9645\u5e94\u7528\u4e2d\uff0c\u805a\u5408\u51fd\u6570\u5f80\u5f80\u4e0d\u5355\u72ec\u4f7f\u7528\u3002\u5b83\u4eec\u53ef\u4ee5\u4e0eGROUP BY<\/code>\u8bed\u53e5\u7ed3\u5408\uff0c\u4ee5\u4fbf\u5bf9\u6570\u636e\u8fdb\u884c\u5206\u7ec4\uff0c\u7136\u540e\u5bf9\u6bcf\u4e2a\u7ec4\u5e94\u7528\u805a\u5408\u51fd\u6570\u3002<\/p>\n<\/p>\n

        \n
      1. \n

        \u4f7f\u7528GROUP BY\u8fdb\u884c\u5206\u7ec4<\/strong><\/p>\n<\/p>\n

        SELECT department, COUNT(*) FROM employees GROUP BY department<\/code>\u6b64\u8bed\u53e5\u5c55\u793a\u4e86\u5982\u4f55\u8ba1\u7b97\u5404\u90e8\u95e8\u7684\u5458\u5de5\u6570\u3002<\/p>\n<\/p>\n<\/li>\n

      2. \n

        HAVING\u5b50\u53e5\u7684\u5e94\u7528<\/strong><\/p>\n<\/p>\n

        \u4e0eWHERE<\/code>\u5b50\u53e5\u7c7b\u4f3c\uff0cHAVING<\/code>\u5b50\u53e5\u7528\u4e8e\u5bf9\u805a\u5408\u7ed3\u679c\u8fdb\u884c\u8fc7\u6ee4\u3002\u4f8b\u5982\uff0cSELECT department, AVG(salary) FROM employees GROUP BY department HAVING AVG(salary) > 5000<\/code>\u5c55\u793a\u4e86\u5982\u4f55\u627e\u51fa\u5e73\u5747\u85aa\u8d44\u8d85\u8fc75000\u7684\u90e8\u95e8\u3002<\/p>\n<\/p>\n<\/li>\n<\/ol>\n

        \u56db\u3001\u805a\u5408\u51fd\u6570\u7684\u9ad8\u7ea7\u5e94\u7528<\/h3>\n<\/p>\n

        \u805a\u5408\u51fd\u6570\u8fd8\u53ef\u4ee5\u4e0e\u5176\u4ed6SQL\u7279\u6027\u7ed3\u5408\uff0c\u4ee5\u5b9e\u73b0\u66f4\u590d\u6742\u7684\u6570\u636e\u5206\u6790\u548c\u62a5\u8868\u751f\u6210\u3002<\/p>\n<\/p>\n

          \n
        1. \n

          \u7a97\u53e3\u51fd\u6570<\/strong><\/p>\n<\/p>\n

          \u7a97\u53e3\u51fd\u6570\u5141\u8bb8\u5bf9\u6570\u636e\u96c6\u8fdb\u884c\u5206\u533a\uff0c\u7136\u540e\u5bf9\u6bcf\u4e2a\u5206\u533a\u5e94\u7528\u805a\u5408\u8fd0\u7b97\uff0c\u800c\u4e0d\u5c06\u884c\u5408\u5e76\u5230\u5355\u4e00\u8f93\u51fa\u884c\u4e2d\u3002\u4f8b\u5982\uff0cSUM(amount) OVER (PARTITION BY customer_id)<\/code>\u53ef\u4ee5\u8ba1\u7b97\u6bcf\u4e2a\u5ba2\u6237\u7684\u603b\u4ea4\u6613\u989d\u3002<\/p>\n<\/p>\n<\/li>\n

        2. \n

          ROLLUP\u4e0eCUBE<\/strong><\/p>\n<\/p>\n

          ROLLUP<\/code>\u548cCUBE<\/code>\u662fGROUP BY<\/code>\u7684\u6269\u5c55\uff0c\u5141\u8bb8\u5728\u5355\u4e2a\u67e5\u8be2\u4e2d\u6267\u884c\u591a\u5c42\u6b21\u7684\u6570\u636e\u805a\u5408\uff0c\u65b9\u4fbf\u8fdb\u884c\u6570\u636e\u6c47\u603b\u548c\u591a\u7ef4\u5ea6\u5206\u6790\u3002<\/p>\n<\/p>\n<\/li>\n<\/ol>\n

          \u805a\u5408\u51fd\u6570\u4e0e\u6a21\u7cca\u67e5\u8be2\u5728\u6570\u636e\u5e93\u67e5\u8be2\u4e2d\u8d77\u5230\u4e86\u6846\u67b6\u6027\u548c\u8865\u5145\u6027\u7684\u53cc\u91cd\u4f5c\u7528\u3002\u638c\u63e1\u5b83\u4eec\u7684\u4f7f\u7528\u65b9\u6cd5\u548c\u573a\u666f\u53ef\u4ee5\u663e\u8457\u63d0\u9ad8\u6570\u636e\u5904\u7406\u7684\u6548\u7387\u548c\u5206\u6790\u7684\u6df1\u5ea6\u3002<\/p>\n<\/p>\n

          \u76f8\u5173\u95ee\u7b54FAQs\uff1a<\/strong><\/h2>\n

          1. \u5982\u4f55\u5728SQL\u4e2d\u8fdb\u884c\u6a21\u7cca\u67e5\u8be2\uff1f<\/strong>
          \n\u5728SQL\u4e2d\u8fdb\u884c\u6a21\u7cca\u67e5\u8be2\u7684\u65b9\u6cd5\u6709\u591a\u79cd\u3002\u6700\u5e38\u89c1\u7684\u65b9\u6cd5\u662f\u4f7f\u7528\u901a\u914d\u7b26\uff0c\u5176\u4e2d\u4f7f\u7528%\u8868\u793a\u5339\u914d\u591a\u4e2a\u5b57\u7b26\u6216\u6ca1\u6709\u5b57\u7b26\uff0c\u4f7f\u7528_\u8868\u793a\u5339\u914d\u4e00\u4e2a\u5b57\u7b26\u3002\u4f8b\u5982\uff0c\u4f7f\u7528LIKE\u8bed\u53e5\u53ef\u4ee5\u5b9e\u73b0\u6a21\u7cca\u67e5\u8be2\uff0c\u4f8b\u5982\uff1a<\/p>\n

          SELECT * FROM \u8868\u540d WHERE \u5217\u540d LIKE '\u5173\u952e\u8bcd%'\n<\/code><\/pre>\n
          \u8fd9\u5c06\u8fd4\u56de\u4ee5\u5173\u952e\u8bcd\u5f00\u5934\u7684\u6240\u6709\u7ed3\u679c\u3002\u60a8\u8fd8\u53ef\u4ee5\u5c06%\u653e\u5728\u5173\u952e\u8bcd\u7684\u4e24\u8fb9\uff0c\u4ee5\u5b9e\u73b0\u5305\u542b\u5173\u952e\u8bcd\u7684\u67e5\u8be2\uff0c\u6216\u8005\u5c06%\u653e\u5728\u5173\u952e\u8bcd\u7684\u672b\u5c3e\uff0c\u4ee5\u5b9e\u73b0\u4ee5\u5173\u952e\u8bcd\u7ed3\u5c3e\u7684\u67e5\u8be2\u3002<\/p>\n
          2. \u5e38\u7528\u7684\u805a\u5408\u51fd\u6570\u6709\u54ea\u4e9b\uff1f<\/strong>
          \n\u5728SQL\u4e2d\uff0c\u805a\u5408\u51fd\u6570\u7528\u4e8e\u5bf9\u6570\u636e\u6267\u884c\u8ba1\u7b97\u5e76\u8fd4\u56de\u5355\u4e2a\u503c\u3002\u5e38\u89c1\u7684\u805a\u5408\u51fd\u6570\u6709\uff1a<\/p>\n
            \n
          • SUM\uff1a\u7528\u4e8e\u8ba1\u7b97\u6307\u5b9a\u5217\u7684\u603b\u548c\u3002<\/li>\n
          • AVG\uff1a\u7528\u4e8e\u8ba1\u7b97\u6307\u5b9a\u5217\u7684\u5e73\u5747\u503c\u3002<\/li>\n
          • COUNT\uff1a\u7528\u4e8e\u8ba1\u7b97\u6307\u5b9a\u5217\u7684\u884c\u6570\u3002<\/li>\n
          • MAX\uff1a\u7528\u4e8e\u8fd4\u56de\u6307\u5b9a\u5217\u4e2d\u7684\u6700\u5927\u503c\u3002<\/li>\n
          • MIN\uff1a\u7528\u4e8e\u8fd4\u56de\u6307\u5b9a\u5217\u4e2d\u7684\u6700\u5c0f\u503c\u3002<\/li>\n<\/ul>\n
            \u8fd9\u4e9b\u805a\u5408\u51fd\u6570\u53ef\u4ee5\u4e0eGROUP BY\u5b50\u53e5\u4e00\u8d77\u4f7f\u7528\uff0c\u4ee5\u6839\u636e\u7279\u5b9a\u7684\u5217\u5bf9\u6570\u636e\u8fdb\u884c\u5206\u7ec4\uff0c\u5e76\u5728\u6bcf\u4e2a\u5206\u7ec4\u4e0a\u6267\u884c\u805a\u5408\u8ba1\u7b97\u3002\u805a\u5408\u51fd\u6570\u5728\u6570\u636e\u5206\u6790\u548c\u62a5\u8868\u751f\u6210\u4e2d\u975e\u5e38\u6709\u7528\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"SQL\u4e2d\u7684\u6a21\u728a\u67e5\u8be2\u4e3b\u8981\u901a\u8fc7LIKE\u5173\u952e\u5b57\u5b9e\u73b0\uff0c\u800c\u5e38\u7528\u7684SQL\u805a\u5408\u51fd\u6570\u5305\u62ecCOUNT()\u3001SUM()\u3001AVG() […]","protected":false},"author":3,"featured_media":312783,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[37],"tags":[],"acf":[],"_links":{"self":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/312746"}],"collection":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/comments?post=312746"}],"version-history":[{"count":0,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/312746\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media\/312783"}],"wp:attachment":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media?parent=312746"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/categories?post=312746"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/tags?post=312746"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}