{"id":87,"date":"2025-11-09T10:00:20","date_gmt":"2025-11-09T02:00:20","guid":{"rendered":"http:\/\/101.132.157.20\/?p=87"},"modified":"2025-11-09T10:00:20","modified_gmt":"2025-11-09T02:00:20","slug":"sql%e6%9f%a5%e8%af%a2%e8%af%ad%e5%8f%a5%e8%bf%9b%e9%98%b6%e7%af%87","status":"publish","type":"post","link":"https:\/\/www.tangent0712.top\/index.php\/2025\/11\/09\/sql%e6%9f%a5%e8%af%a2%e8%af%ad%e5%8f%a5%e8%bf%9b%e9%98%b6%e7%af%87\/","title":{"rendered":"SQL\u67e5\u8be2\u8bed\u53e5(\u8fdb\u9636\u7bc7)"},"content":{"rendered":"

LIKE \u67e5\u627e\u7c7b\u4f3c\u503c<\/h3>\n

\u200bLIKE\u200b\u5173\u952e\u5b57\u7528\u4e8e\u903b\u8f91\u8868\u8fbe\u5f0f,\u8fd4\u56de\u4e00\u4e2a\u5e03\u5c14\u503c<\/p>\n

\u200bWHERE\u200b\u5b50\u53e5\u7684\u683c\u5f0f:<\/p>\n

WHERE\n    column_name LIKE String \n<\/code><\/pre>\n
\u5176\u4e2d,String\u200b\u53ef\u4ee5\u5305\u542b\u901a\u914d\u7b26:<\/p>\n
    \n
  • \u200b%\u200b\uff1a\u5339\u914d\u4efb\u610f\u5b57\u7b26(\u5305\u62ec\u96f6\u4e2a\u5b57\u7b26)<\/li>\n\n
  • \u200b_\u200b\uff1a\u5339\u914d\u5355\u4e2a\u5b57\u7b26<\/li>\n<\/ul>\n
    \u793a\u4f8b(\u641c\u7d22Person\u200b\u8868\u4e2dName\u200b\u5b57\u6bb5\u4e2d\u4ee5Tangent\u200b\u5f00\u5934\u7684\u884c):<\/p>\n
    SELECT\n    Name\nFROM\n    Person\nWHERE\n    Name LIKE 'Tangent%';\n<\/code><\/pre>\n
    \u76f8\u4f3c\u5730,NOT LIKE\u200b\u5173\u952e\u5b57\u53ef\u4ee5\u8fbe\u5230\u76f8\u53cd\u7684\u6548\u679c<\/p>\n
    IN \u5173\u952e\u5b57<\/h3>\n
    \u200bIN\u200b\u5173\u952e\u5b57\u7528\u5728\u903b\u8f91\u8868\u8fbe\u5f0f\u4e2d,\u548c=\u200b\u4e0eOR\u200b\u7684\u7ec4\u5408\u7b49\u4ef7<\/p>\n
    WHERE\n    Name='A' OR Name='B'\nWHERE\n    Name IN ('A','B')\n--\u4ee5\u4e0a\u4e24\u79cd\u5199\u6cd5\u662f\u7b49\u4ef7\u7684\n<\/code><\/pre>\n
    BETWEEN \u9009\u53d6\u533a\u95f4\u6570\u636e<\/h3>\n
    \u200bBETWEEN A AND B\u200b\u4f1a\u5bf9\u6570\u636e(\u6570\u503c,\u5b57\u7b26\u4e32,\u65e5\u671f)\u8fdb\u884c\u5224\u5b9a.<\/p>\n
    \u5bf9\u5b57\u7b26\u4e32\u8fdb\u884c\u5224\u5b9a\u7684\u65f6\u5019,\u5c06\u6839\u636eASCII\u7801\u9010\u4f4d\u5224\u5b9a.<\/p>\n
    \u793a\u4f8b:<\/p>\n
    WHERE\n    Age BETWEEN 18 AND 25\n<\/code><\/pre>\n
    \u8fd9\u6761WHERE\u8bed\u53e5\u5c06\u5bf9\u5e74\u9f84\u5904\u4e8e18\u548c25\u4e4b\u95f4\u7684\u884c\u8fd4\u56detrue<\/p>\n
    \u200bNOT BETWEEN\u200b\u4f1a\u4ea7\u751f\u76f8\u53cd\u7684\u7ed3\u679c<\/p>\n
    \n
    \u6ce8\u610f:\u4e0d\u540c\u7684\u6570\u636e\u5e93\u7ba1\u7406\u7cfb\u7edf\u5bf9\u4e8eBETWEEN\u7684\u5f00\u95ed\u533a\u95f4\u7684\u5904\u7406\u662f\u4e0d\u4e00\u81f4\u7684,\u52a1\u5fc5\u719f\u6089\u6240\u4f7f\u7528\u7684\u6570\u636e\u5e93\u7ba1\u7406\u7cfb\u7edf<\/p>\n<\/blockquote>\n
    AS \u522b\u540d<\/h3>\n
      \n
    • \u5b57\u6bb5\u540e\u7684AS\u53ef\u4ee5\u6307\u5b9a\u8f93\u51fa\u7684\u5217\u540d\u79f0<\/li>\n\n
    • \u8868\u540d\u79f0\u540e\u7684AS\u53ef\u4ee5\u6307\u5b9a\u8f93\u51fa\u7684\u8868\u540d\u79f0<\/li>\n<\/ul>\n
      SELECT\n    c.ID,c.Name\nFROM\n    Class c;\n<\/code><\/pre>\n
      AS\u5176\u5b9e\u662f\u53ef\u4ee5\u7701\u7565\u7684<\/p>\n
      JOIN \u591a\u8868\u5173\u8054<\/h3>\n
      \u6ce8\u610f:\u4e0b\u9762\u7684\u8868\u683c\u4e2d,\u5de6\u8868\u4ee3\u8868\u4e3b\u8868,\u53f3\u8868\u4ee3\u8868\u4ece\u8868<\/p>\n
      INNER JOIN<\/th>\n\u8fd4\u56de\u4e24\u4e2a\u8868\u4e2d\u6ee1\u8db3\u8fde\u63a5\u6761\u4ef6\u7684\u8bb0\u5f55(\u53d6\u4ea4\u96c6),\u53ea\u6709\u4e24\u8868\u4e2d\u5339\u914d\u7684\u884c\u624d\u4f1a\u88ab\u8fd4\u56de<\/th><\/tr><\/thead>\n
      LEFT JOIN<\/td>\n\u8fd4\u56de\u5de6\u8868\u4e2d\u7684\u6240\u6709\u8bb0\u5f55\uff0c\u5373\u4f7f\u53f3\u8868\u4e2d\u6ca1\u6709\u5339\u914d\u7684\u8bb0\u5f55(\u4ee5\u5de6\u8868\u4e3a\u4e3b)<\/td><\/tr>\n
      RIGHT JOIN<\/td>\n\u8fd4\u56de\u53f3\u8868\u4e2d\u7684\u6240\u6709\u8bb0\u5f55\uff0c\u5373\u4f7f\u5de6\u8868\u4e2d\u6ca1\u6709\u5339\u914d\u7684\u8bb0\u5f55(\u4ee5\u53f3\u8868\u4e3a\u4e3b)<\/td><\/tr>\n
      FULL OUTER JOIN<\/td>\n\u8fd4\u56de\u4e24\u4e2a\u8868\u7684\u5e76\u96c6<\/td><\/tr>\n
      CROSS JOIN<\/td>\n\u8fd4\u56de\u4e24\u4e2a\u8868\u7684\u7b1b\u5361\u5c14\u79ef\uff0c\u6bcf\u6761\u5de6\u8868\u8bb0\u5f55\u4e0e\u6bcf\u6761\u53f3\u8868\u8bb0\u5f55\u8fdb\u884c\u7ec4\u5408\u3002<\/td><\/tr>\n
      SELF JOIN<\/td>\n\u5c06\u4e00\u4e2a\u8868\u4e0e\u81ea\u8eab\u8fde\u63a5\u3002<\/td><\/tr>\n
      NATURAL JOIN<\/td>\n\u57fa\u4e8e\u540c\u540d\u5b57\u6bb5\u81ea\u52a8\u5339\u914d\u8fde\u63a5\u7684\u8868\u3002<\/td><\/tr><\/tbody><\/table><\/figure>\n
      SELECT\n    column1,column2...\nFROM\n    table1\nJOIN\n    table2 ON Boolean;\n<\/code><\/pre>\n
      JOIN\u5b50\u53e5\u4f1a\u904d\u5386\u4e24\u4e2a\u8868\u4e2d\u6240\u6709\u884c\u7684\u7ec4\u5408,\u6309\u7167JOIN\u524d\u7684\u5173\u952e\u5b57\u8fd4\u56deON\u5173\u952e\u5b57\u540e\u9762Boolean\u4e3atrue\u7684\u884c<\/p>\n
      UNION \u5408\u5e76\u7ed3\u679c\u96c6<\/h3>\n
      UNION\u8fde\u63a5\u4e24\u4e2aSELECT\u8bed\u53e5,\u8fd4\u56de\u4e24\u4e2a\u7ed3\u679c\u96c6\u7684\u5408\u5e76<\/p>\n
      UNION\u8fd4\u56de\u7684\u5185\u5bb9\u9ed8\u8ba4\u9009\u53d6\u4e0d\u540c\u7684\u503c,\u82e5\u8981\u4fdd\u7559\u91cd\u590d\u7684\u503c,\u4f7f\u7528UNION ALL<\/p>\n
      \u6ce8\u610f:\u4e24\u4e2a\u5f85\u5408\u5e76\u7684\u7ed3\u679c\u96c6\u5fc5\u987b\u6709\u76f8\u540c\u6570\u91cf\u7684\u5217,\u5217\u4e2d\u4e5f\u5fc5\u987b\u6709\u76f8\u4f3c\u7684\u6570\u636e\u7c7b\u578b,\u8bf7\u6ce8\u610fSELECT\u5173\u952e\u5b57\u540e\u9762\u8fd4\u56de\u7684\u5b57\u6bb5\u987a\u5e8f<\/p>\n
      select \n    * \nFROM \n    persons\nUNION\nselect \n    * \nFROM  \n    persons_b;\n<\/code><\/pre>\n
      NOT NULL \u975e\u7a7a<\/h3>\n
      NOT NULL\u5173\u952e\u5b57\u7528\u5728\u903b\u8f91\u8868\u8fbe\u5f0f\u4e2d,\u6765\u5224\u65ad\u67d0\u4e00\u884c\u7684\u7279\u5b9a\u5b57\u6bb5\u662f\u5426\u662f\u7a7a\u7684<\/p>\n
      NOT NULL\u5173\u952e\u5b57\u7528\u5728\u5efa\u8868\u8bed\u53e5\u4e2d,\u6765\u7ea6\u675f\u67d0\u4e00\u4e2a\u5b57\u6bb5\u4e0d\u80fd\u662f\u7a7a\u7684<\/p>\n
      CREATE TABLE table_name(\n    column int NOT NULL\n);\n<\/code><\/pre>\n
      SELECT\n    *\nFROM\n    Persons\nWHERE\n    Name IS NOT NULL\n<\/code><\/pre>\n
      IS NULL \u7528\u5728\u5e03\u5c14\u8868\u8fbe\u5f0f\u4e2d,\u6548\u679c\u4e0eIS NOT NULL\u76f8\u53cd<\/p>\n
      VIEW \u89c6\u56fe<\/h3>\n
      \u89c6\u56fe\u5305\u542b\u884c\u548c\u5217\uff0c\u5c31\u50cf\u4e00\u4e2a\u771f\u5b9e\u7684\u8868\u3002\u89c6\u56fe\u4e2d\u7684\u5b57\u6bb5\u5c31\u662f\u6765\u81ea\u4e00\u4e2a\u6216\u591a\u4e2a\u6570\u636e\u5e93\u4e2d\u7684\u771f\u5b9e\u7684\u8868\u4e2d\u7684\u5b57\u6bb5\u3002<\/p>\n
      CREATE VIEW view_name AS\nSELECT \n    column1, column2, ...\nFROM \n    table_name\nWHERE \n    Boolean;\n<\/code><\/pre>\n
      \u89c6\u56fe\u662f\u57fa\u4e8e\u67e5\u8be2\u7ed3\u679c\u751f\u6210\u7684\u865a\u62df\u8868\uff0c\u800c\u4e0d\u662f\u5b9e\u9645\u5b58\u50a8\u6570\u636e\u7684\u8868.\u89c6\u56fe\u53ef\u4ee5\u586b\u5165\u540e\u9762\u8bed\u53e5\u7684table_name\u5185<\/p>\n
      \u5220\u9664\u89c6\u56fe\u53ef\u4ee5\u4f7f\u7528DROP VIEW\u5173\u952e\u5b57<\/p>\n
      DROP VIEW\n    view_name\n<\/code><\/pre>\n
      \n
      \u867d\u7136\u8bf4\u662f\u8fdb\u9636\u7bc7,\u4f46\u8fd8\u662f\u4e00\u4e9b\u5f88\u57fa\u7840\u7684\u4e1c\u897f,\u800c\u4e14\u90fd\u662f\u7c97\u7565\u4ecb\u7ecd,\u4e0b\u4e00\u7bc7\u4f1a\u5199\u4e00\u4e0bSQL\u4e2d\u7684\u51fd\u6570,\u91cd\u96be\u70b9\u4ee5\u540e\u4f1a\u5355\u72ec\u5199\u6587\u7ae0\u7684(\u6e9c\u53bb\u5199\u8fd0\u8f6c\u65e5\u5fd7\u4e86)<\/p>\n<\/blockquote>","protected":false},"excerpt":{"rendered":"
      LIKE \u67e5\u627e\u7c7b\u4f3c\u503c \u200bLIKE\u200b\u5173\u952e\u5b57\u7528\u4e8e\u903b\u8f91\u8868\u8fbe\u5f0f,\u8fd4\u56de\u4e00\u4e2a\u5e03\u5c14\u503c \u200bWHERE\u200b\u5b50\u53e5\u7684\u683c\u5f0f: \u5176\u4e2d,St […]<\/p>","protected":false},"author":1,"featured_media":88,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11,3],"tags":[],"class_list":["post-87","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-11","category-coding"],"_links":{"self":[{"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/posts\/87","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/comments?post=87"}],"version-history":[{"count":1,"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/posts\/87\/revisions"}],"predecessor-version":[{"id":89,"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/posts\/87\/revisions\/89"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/media\/88"}],"wp:attachment":[{"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/media?parent=87"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/categories?post=87"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.tangent0712.top\/index.php\/wp-json\/wp\/v2\/tags?post=87"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}