{"id":14214,"date":"2023-12-04T00:52:29","date_gmt":"2023-12-03T16:52:29","guid":{"rendered":"https:\/\/wx.kaifamiao.info\/?p=14214"},"modified":"2023-12-04T00:53:17","modified_gmt":"2023-12-03T16:53:17","slug":"mybatis-shi-xian-yi-dui-yi-you-ji-zhong-fang-shi-j","status":"publish","type":"post","link":"http:\/\/wx.kaifamiao.info\/index.php\/2023\/12\/04\/mybatis-shi-xian-yi-dui-yi-you-ji-zhong-fang-shi-j\/","title":{"rendered":"MyBatis \u5b9e\u73b0\u4e00\u5bf9\u4e00\u6709\u51e0\u79cd\u65b9\u5f0f\uff1f\u5177\u4f53\u600e\u4e48\u64cd\u4f5c\u7684\uff1f"},"content":{"rendered":"<p>MyBatis \u5b9e\u73b0\u4e00\u5bf9\u4e00\u5173\u8054\u67e5\u8be2\u901a\u5e38\u4f7f\u7528\u5d4c\u5957\u67e5\u8be2\u6216\u8005\u5d4c\u5957\u7ed3\u679c\u7684\u65b9\u5f0f\u3002<\/p>\n<h3>1. \u5d4c\u5957\u67e5\u8be2\uff08Nested Queries\uff09<\/h3>\n<h4>\u6b65\u9aa4\uff1a<\/h4>\n<ol>\n<li><strong>\u5b9a\u4e49\u4e24\u4e2a SQL \u67e5\u8be2\u8bed\u53e5\uff1a<\/strong> \u4e00\u4e2a\u67e5\u8be2\u4e3b\u5bf9\u8c61\uff0c\u53e6\u4e00\u4e2a\u67e5\u8be2\u5173\u8054\u5bf9\u8c61\u3002<\/p>\n<\/li>\n<li>\n<p><strong>\u5728\u4e3b\u67e5\u8be2\u7684 ResultMap \u4e2d\u4f7f\u7528 <code>&lt;association&gt;<\/code> \u5143\u7d20\u8fdb\u884c\u5173\u8054\u6620\u5c04\uff1a<\/strong> \u4f7f\u7528 <code>&lt;association&gt;<\/code> \u5143\u7d20\u6765\u6620\u5c04\u5173\u8054\u5bf9\u8c61\uff0c\u5e76\u6307\u5b9a\u5173\u8054\u67e5\u8be2\u8bed\u53e5\u3002<\/p>\n<\/li>\n<\/ol>\n<p>\u793a\u4f8b\uff1a<\/p>\n<pre data-language=XML><code class=\"language-markup  line-numbers\">&lt;!-- \u4e3b\u5bf9\u8c61\u67e5\u8be2 --&gt;\n&lt;select id=\"getUserById\" resultMap=\"userWithDetailResult\"&gt;\n    SELECT * FROM users WHERE user_id = #{userId}\n&lt;\/select&gt;\n\n&lt;!-- \u5173\u8054\u5bf9\u8c61\u67e5\u8be2 --&gt;\n&lt;select id=\"getUserDetailById\" resultMap=\"userDetailResult\"&gt;\n    SELECT * FROM user_details WHERE user_id = #{userId}\n&lt;\/select&gt;\n\n&lt;!-- \u4e3b\u5bf9\u8c61 ResultMap --&gt;\n&lt;resultMap id=\"userWithDetailResult\" type=\"User\"&gt;\n    &lt;id property=\"id\" column=\"user_id\"\/&gt;\n    &lt;result property=\"username\" column=\"username\"\/&gt;\n    &lt;!-- \u5d4c\u5957\u67e5\u8be2\u5173\u8054\u5bf9\u8c61 --&gt;\n    &lt;association property=\"detail\" ofType=\"UserDetail\" select=\"getUserDetailById\"\/&gt;\n&lt;\/resultMap&gt;\n<\/code><\/pre>\n<h3>2. \u5d4c\u5957\u7ed3\u679c\uff08Nested Results\uff09<\/h3>\n<h4>\u6b65\u9aa4\uff1a<\/h4>\n<ol>\n<li><strong>\u5b9a\u4e49\u5355\u4e2a SQL \u67e5\u8be2\u8bed\u53e5\uff1a<\/strong> \u5728\u67e5\u8be2\u4e2d\u5305\u542b\u5173\u8054\u5bf9\u8c61\u7684\u5b57\u6bb5\uff0c\u5e76\u4f7f\u7528\u5d4c\u5957\u7684 <code>&lt;resultMap&gt;<\/code> \u6765\u6620\u5c04\u5173\u8054\u5bf9\u8c61\u3002<\/li>\n<\/ol>\n<p>\u793a\u4f8b\uff1a<\/p>\n<pre data-language=XML><code class=\"language-markup  line-numbers\">&lt;!-- \u5355\u4e2a\u67e5\u8be2\u8bed\u53e5\uff0c\u540c\u65f6\u83b7\u53d6\u4e3b\u5bf9\u8c61\u548c\u5173\u8054\u5bf9\u8c61 --&gt;\n&lt;select id=\"getUserWithDetail\" resultMap=\"userWithDetailResult\"&gt;\n    SELECT u.user_id, u.username, ud.address, ud.phone_number\n    FROM users u LEFT JOIN user_details ud ON u.user_id = ud.user_id\n    WHERE u.user_id = #{userId}\n&lt;\/select&gt;\n\n&lt;!-- \u5d4c\u5957\u7684 ResultMap --&gt;\n&lt;resultMap id=\"userWithDetailResult\" type=\"User\"&gt;\n    &lt;id property=\"id\" column=\"user_id\"\/&gt;\n    &lt;result property=\"username\" column=\"username\"\/&gt;\n    &lt;!-- \u5d4c\u5957\u5173\u8054\u5bf9\u8c61\u7684 ResultMap --&gt;\n    &lt;association property=\"detail\" javaType=\"UserDetail\" resultMap=\"userDetailResult\"\/&gt;\n&lt;\/resultMap&gt;\n<\/code><\/pre>\n<p>\u8fd9\u4e24\u79cd\u65b9\u5f0f\u5747\u53ef\u5b9e\u73b0\u4e00\u5bf9\u4e00\u5173\u8054\u67e5\u8be2\uff0c\u53ef\u4ee5\u6839\u636e\u5b9e\u9645\u60c5\u51b5\u9009\u62e9\u66f4\u9002\u5408\u7684\u65b9\u5f0f\u6765\u67e5\u8be2\u548c\u6620\u5c04\u4e00\u5bf9\u4e00\u5173\u8054\u7684\u5bf9\u8c61\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>MyBatis \u5b9e\u73b0\u4e00\u5bf9\u4e00\u5173\u8054\u67e5\u8be2\u901a\u5e38\u4f7f\u7528\u5d4c\u5957\u67e5\u8be2\u6216\u8005\u5d4c\u5957\u7ed3\u679c\u7684\u65b9\u5f0f\u3002 1. \u5d4c\u5957\u67e5\u8be2\uff08Nested Quer [&hellip;]<\/p>\n","protected":false},"author":11,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[113],"tags":[],"class_list":["post-14214","post","type-post","status-publish","format-standard","hentry","category-mybatis"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/14214","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/comments?post=14214"}],"version-history":[{"count":1,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/14214\/revisions"}],"predecessor-version":[{"id":14215,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/14214\/revisions\/14215"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=14214"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=14214"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=14214"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}