{"id":3947,"date":"2022-09-15T15:48:50","date_gmt":"2022-09-15T07:48:50","guid":{"rendered":"https:\/\/www.zeroheart.xyz\/wordpress\/?p=3947"},"modified":"2022-09-15T15:48:50","modified_gmt":"2022-09-15T07:48:50","slug":"mybatis%e5%88%86%e9%a1%b5%e6%8f%92%e4%bb%b6%e4%b8%8d%e5%ae%89%e5%85%a8%e7%9a%84%e6%83%85%e5%86%b5","status":"publish","type":"post","link":"https:\/\/www.zeroheart.xyz\/wordpress\/?p=3947","title":{"rendered":"mybatis\u5206\u9875\u63d2\u4ef6\u4e0d\u5b89\u5168\u7684\u60c5\u51b5"},"content":{"rendered":"\n<p><a href=\"https:\/\/github.com\/pagehelper\/Mybatis-PageHelper\/blob\/master\/wikis\/en\/HowToUse.md\">Mybatis-PageHelper\/HowToUse.md at master \u00b7 pagehelper\/Mybatis-PageHelper (github.com)<\/a><\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u4ec0\u4e48\u65f6\u5019\u4f1a\u5bfc\u81f4\u4e0d\u5b89\u5168\u7684\u5206\u9875\uff1f<\/h5>\n\n\n\n<p><code>PageHelper<\/code>&nbsp;\u65b9\u6cd5\u4f7f\u7528\u4e86\u9759\u6001\u7684&nbsp;<code>ThreadLocal<\/code>&nbsp;\u53c2\u6570\uff0c\u5206\u9875\u53c2\u6570\u548c\u7ebf\u7a0b\u662f\u7ed1\u5b9a\u7684\u3002<\/p>\n\n\n\n<p>\u53ea\u8981\u4f60\u53ef\u4ee5\u4fdd\u8bc1\u5728&nbsp;<code>PageHelper<\/code>&nbsp;\u65b9\u6cd5\u8c03\u7528\u540e\u7d27\u8ddf MyBatis \u67e5\u8be2\u65b9\u6cd5\uff0c\u8fd9\u5c31\u662f\u5b89\u5168\u7684\u3002\u56e0\u4e3a&nbsp;<code>PageHelper<\/code>&nbsp;\u5728&nbsp;<code>finally<\/code>&nbsp;\u4ee3\u7801\u6bb5\u4e2d\u81ea\u52a8\u6e05\u9664\u4e86&nbsp;<code>ThreadLocal<\/code>&nbsp;\u5b58\u50a8\u7684\u5bf9\u8c61\u3002<\/p>\n\n\n\n<p>\u5982\u679c\u4ee3\u7801\u5728\u8fdb\u5165&nbsp;<code>Executor<\/code>&nbsp;\u524d\u53d1\u751f\u5f02\u5e38\uff0c\u5c31\u4f1a\u5bfc\u81f4\u7ebf\u7a0b\u4e0d\u53ef\u7528\uff0c\u8fd9\u5c5e\u4e8e\u4eba\u4e3a\u7684 Bug\uff08\u4f8b\u5982\u63a5\u53e3\u65b9\u6cd5\u548c XML \u4e2d\u7684\u4e0d\u5339\u914d\uff0c\u5bfc\u81f4\u627e\u4e0d\u5230&nbsp;<code>MappedStatement<\/code>&nbsp;\u65f6\uff09\uff0c \u8fd9\u79cd\u60c5\u51b5\u7531\u4e8e\u7ebf\u7a0b\u4e0d\u53ef\u7528\uff0c\u4e5f\u4e0d\u4f1a\u5bfc\u81f4&nbsp;<code>ThreadLocal<\/code>&nbsp;\u53c2\u6570\u88ab\u9519\u8bef\u7684\u4f7f\u7528\u3002<\/p>\n\n\n\n<p>\u4f46\u662f\u5982\u679c\u4f60\u5199\u51fa\u4e0b\u9762\u8fd9\u6837\u7684\u4ee3\u7801\uff0c\u5c31\u662f\u4e0d\u5b89\u5168\u7684\u7528\u6cd5\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">PageHelper.startPage(1, 10);\nList&lt;User&gt; list;\nif(param1 != null){\n    list = userMapper.selectIf(param1);\n} else {\n    list = new ArrayList&lt;User&gt;();\n}<\/pre>\n\n\n\n<p>\u8fd9\u79cd\u60c5\u51b5\u4e0b\u7531\u4e8e param1 \u5b58\u5728 null \u7684\u60c5\u51b5\uff0c\u5c31\u4f1a\u5bfc\u81f4 PageHelper \u751f\u4ea7\u4e86\u4e00\u4e2a\u5206\u9875\u53c2\u6570\uff0c\u4f46\u662f\u6ca1\u6709\u88ab\u6d88\u8d39\uff0c\u8fd9\u4e2a\u53c2\u6570\u5c31\u4f1a\u4e00\u76f4\u4fdd\u7559\u5728\u8fd9\u4e2a\u7ebf\u7a0b\u4e0a\u3002\u5f53\u8fd9\u4e2a\u7ebf\u7a0b\u518d\u6b21\u88ab\u4f7f\u7528\u65f6\uff0c\u5c31\u53ef\u80fd\u5bfc\u81f4\u4e0d\u8be5\u5206\u9875\u7684\u65b9\u6cd5\u53bb\u6d88\u8d39\u8fd9\u4e2a\u5206\u9875\u53c2\u6570\uff0c\u8fd9\u5c31\u4ea7\u751f\u4e86\u83ab\u540d\u5176\u5999\u7684\u5206\u9875\u3002<\/p>\n\n\n\n<p>\u4e0a\u9762\u8fd9\u4e2a\u4ee3\u7801\uff0c\u5e94\u8be5\u5199\u6210\u4e0b\u9762\u8fd9\u4e2a\u6837\u5b50\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">List&lt;User> list;\nif(param1 != null){\n    PageHelper.startPage(1, 10);\n    list = userMapper.selectIf(param1);\n} else {\n    list = new ArrayList&lt;User>();\n}\n\n\u53ea\u8981\u6b63\u786e\u7684\u4f7f\u7528\uff0c\u5c31\u4e0d\u9700\u8981\u624b\u52a8\u91ca\u653ethreadlocal\u7684\u5206\u9875\u6570\u636e\n\n<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Mybatis-PageHelper\/HowToUse.md at master \u00b7 pagehelper\/M [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[233],"_links":{"self":[{"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/3947"}],"collection":[{"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3947"}],"version-history":[{"count":2,"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/3947\/revisions"}],"predecessor-version":[{"id":3949,"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/3947\/revisions\/3949"}],"wp:attachment":[{"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3947"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3947"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3947"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}