{"id":1399,"date":"2016-01-02T15:19:07","date_gmt":"2016-01-02T07:19:07","guid":{"rendered":"http:\/\/www.821121.com\/?p=1399"},"modified":"2021-02-02T18:03:27","modified_gmt":"2021-02-02T10:03:27","slug":"hint%e7%9a%84%e4%b8%8d%e6%ad%a3%e7%a1%ae%e5%86%99%e6%b3%95","status":"publish","type":"post","link":"http:\/\/www.821121.com\/?p=1399","title":{"rendered":"Hint\u7684\u4e0d\u6b63\u786e\u5199\u6cd5"},"content":{"rendered":"<p>\u662f\u4e00\u4e2a\u6bd4\u8f83\u4e0d\u5bb9\u6613\u53d1\u73b0\u7684\u95ee\u9898\u3002\u4e0b\u9762\u51e0\u6761SQL\uff0c\u54ea\u4e00\u6761SQL\u7684append hint\u4f1a\u751f\u6548\uff1a<\/p>\n<pre><code class=\"language-sql\">1. INSERT \/*+ append,parallel(t1) *\/ INTO T1 SELECT * FROM T2;  \n2. INSERT \/*+ parallel(t1), append *\/ INTO T1 SELECT * FROM T2;  \n3. INSERT \/*+ this is append *\/ INTO T1 SELECT * FROM T2;  \n4. INSERT \/*+ this append *\/ INTO T1 SELECT * FROM T2;  <\/code><\/pre>\n<p>\u8981\u56de\u7b54\u8fd9\u4e2a\u95ee\u9898\uff0c\u8bf7\u5148\u770b\u4e0b\u9762\u7684\u6d4b\u8bd5\uff08\u6d4b\u8bd5\u73af\u5883\uff1a10.2.0.1 for Windows\uff09\uff1a<\/p>\n<pre><code class=\"language-sql\">\nSQL&gt; INSERT \/*+ append,parallel(t1) *\/ INTO T1 SELECT * FROM T2;  \n\u5df2\u521b\u5efa55640\u884c\u3002  \n\u7edf\u8ba1\u4fe1\u606f  \n----------------------------------------------------------  \n      12304  redo size  \nSQL&gt; COMMIT;  \n\nSQL&gt; INSERT \/*+ parallel(t1), append *\/ INTO T1 SELECT * FROM T2;  \n\u5df2\u521b\u5efa55640\u884c\u3002  \n\u7edf\u8ba1\u4fe1\u606f  \n----------------------------------------------------------  \n    5739584  redo size  \nSQL&gt; COMMIT;  \n\nSQL&gt; INSERT \/*+ this is append *\/ INTO T1 SELECT * FROM T2;  \n\u5df2\u521b\u5efa55640\u884c\u3002  \n\u7edf\u8ba1\u4fe1\u606f  \n----------------------------------------------------------  \n    5746604  redo size  \nSQL&gt; COMMIT;  \n\nSQL&gt; INSERT \/*+ this append *\/ INTO T1 SELECT * FROM T2;  \n\u5df2\u521b\u5efa55640\u884c\u3002  \n\u7edf\u8ba1\u4fe1\u606f  \n----------------------------------------------------------  \n      12052  redo size  \nSQL&gt; COMMIT;  <\/code><\/pre>\n<p>\u4ece\u4e0a\u9762\u7684\u8f93\u51fa\u53ef\u4ee5\u770b\u5230\uff0c\u901a\u8fc7insert\u8bed\u53e5\u6267\u884c\u4ea7\u751f\u7684redo size\u5224\u65ad\uff0c4\u6761SQL\u8bed\u53e5\u4e2d\uff0c1\u548c4\u8fd92\u6761SQL\u4e2d\u7684append hint\u8d77\u4e86\u4f5c\u7528\uff0c\u800c2\u548c3\u8fd92\u6761SQL\u4e2d\u7684append hint\u6ca1\u6709\u8d77\u4f5c\u7528\u3002\u6211\u4eec\u770b\u770b\u7b2c1\u548c\u7b2c2\u6761SQL\uff0c\u53ea\u4e0d\u8fc7\u662fparallel\u548cappend\u6362\u4e86\u4e2a\u4f4d\u7f6e\uff0c\u7ed3\u679c\u5c31\u622a\u7136\u4e0d\u540c\uff1b\u800c\u7b2c3\u548c\u7b2c4\u6761SQL\uff0c\u53ea\u662f\u4e00\u4e2a\u591a\u4e86&quot;is&quot;\u8fd9\u4e2a\u8bcd\uff0c\u53e6\u4e00\u4e2a\u6ca1\u6709\uff0c\u5176\u7ed3\u679c\u4e5f\u5b8c\u5168\u4e0d\u540c\u3002\u8fd9\u91cc\u6709\u4ec0\u4e48\u7384\u673a\u5417\uff1f<\/p>\n<p>\u8fd9\u91cc\u5c31\u9700\u8981\u4e86\u89e3Oracle\u5728\u89e3\u6790SQL\u65f6\uff0c\u662f\u600e\u6837\u89e3\u6790hint\u7684\u3002<br \/>\nOracle\u5728\u89e3\u6790hint\uff0c\u4ece\u5de6\u5230\u53f3\u8fdb\u884c\uff0c\u5982\u679c\u9047\u5230\u4e00\u4e2a\u8bcd\u662foracle\u5173\u952e\u5b57\u6216\u8005\u8bf4\u662f\u4fdd\u7559\u5b57\uff0c\u5c06\u5ffd\u7565\u8fd9\u4e2a\u8bcd\u4ee5\u53ca\u4e4b\u540e\u7684\u6240\u6709\u8bcd\u3002\u5982\u679c\u9047\u5230\u7684\u4e00\u4e2a\u8bcd\u5373\u4e0d\u662f\u5173\u952e\u5b57\u4e5f\u4e0d\u662fhint\uff0c\u5c31\u5ffd\u7565\u8be5\u8bcd\u3002\u5982\u679c\u9047\u5230\u7684\u4e00\u4e2a\u8bcd\u662f\u6709\u6548\u7684hint\uff0c\u90a3\u4e48\u5c31\u4f1a\u4fdd\u7559\u8be5hint\u3002<\/p>\n<p>Oracle\u7684\u4fdd\u7559\u5b57\u6216\u8005\u8bf4\u662f\u5173\u952e\u8bcd\uff08\u867d\u7136\u4e8c\u8005\u5728\u610f\u4e49\u4e0d\u4e00\u6837\uff0c\u4f46\u8fd9\u91cc\u4e0d\u5c06\u5176\u533a\u5206\uff09\uff0c\u53ef\u4ee5\u901a\u8fc7\u89c6\u56fev$reserved_words\u6765\u67e5\u8be2\u3002&quot;is&quot;\u6b63\u662f\u4e00\u4e2a\u5173\u952e\u8bcd\uff0c\u751a\u81f3\u8fde&quot;,&quot;\uff08\u9017\u53f7\uff09\u4e5f\u662f\u4e00\u4e2a\u5173\u952e\u8bcd\u3002\u8fd9\u6837\uff0c\u4e0a\u9762\u7684\u7b2c2\u548c\u7b2c3\u6761SQL\uff0cOracle\u89e3\u6790\u65f6\u5f53\u9047\u5230&quot;,&quot;\u548c&quot;is&quot;\u65f6\uff0c\u5c31\u5ffd\u7565\u4e86\u540e\u9762\u7684\u6240\u6709hint\u3002\u5728\u7b2c4\u6761SQL\u4e2d\uff0cthis\u5e76\u4e0d\u662f\u4e00\u4e2a\u5173\u952e\u8bcd\uff0c\u6240\u4ee5append hint\u6709\u6548\u3002\u57fa\u4e8e\u8fd9\u4e2a\u539f\u7406\uff0c\u4e0b\u9762\u7684\u4e00\u6761SQL\u4e2d\u7684hint\u4e5f\u662f\u4e0d\u8d77\u4f5c\u7528\u7684\uff1a<\/p>\n<pre><code class=\"language-sql\">INSERT \/*+ NOLOGGING APPEND *\/ INTO T1 SELECT * FROM T2; <\/code><\/pre>\n<p>\u57289.2.0.8\u548c11.2.0.2\u8fd92\u4e2a\u7248\u672c\u4e0b\u8fdb\u884c\u540c\u6837\u7684\u6d4b\u8bd5\uff0c\u7ed3\u679c\u5b8c\u5168\u4e00\u6837\u3002<br \/>\n\u4e3a\u4e86\u907f\u514d\u8fd9\u6837\u7684\u60c5\u51b5\uff0c\u5728SQL\u4e2d\u4e66\u5199hint\u65f6\uff0c\u5728\/<em>+ <\/em>\/\u548c--+\u8fd92\u79cd\u7ed3\u6784\u5185\u53ea\u5199hint\uff0c\u800c\u4e0d\u8981\u5199\u9017\u53f7\uff0c\u6216\u8005\u662f\u5176\u4ed6\u7684\u6ce8\u91ca\u3002\u5982\u679c\u8981\u5bf9SQL\u5199\u6ce8\u91ca\uff0c\u5728\u4e13\u95e8\u7684\u6ce8\u91ca\u7ed3\u6784\u4e2d\u5199\u5165\u3002\u6bd4\u5982\/<em> test comment <\/em>\/\u3002\u5982\u679c\u4e0ehint\u6df7\u5199\u6ce8\u91ca\uff0c\u867d\u7136\u5f53\u65f6\u6ca1\u6709\u5173\u952e\u8bcd\u5728\u91cc\u9762\uff0c\u4f46\u968f\u7740\u7248\u672c\u5347\u7ea7\uff0c\u5f88\u53ef\u80fd\u4f1a\u52a0\u5165\u65b0\u7684\u5173\u952e\u8bcd\u3002<\/p>\n<p>\u53e6\u5916\uff0c\u4e00\u4e9b\u5f88\u5e38\u89c1\u7684hint\u5f62\u5f0f\uff0c\u6bd4\u5982\/<em>+ parallel(t,8) <\/em>\/\uff0c\/<em>+ index(t,t_idx) <\/em>\/\uff0c\u867d\u7136\u5f53\u524d\u6ca1\u6709\u95ee\u9898\uff0c\u4f46\u6807\u51c6\u7684\u5199\u6cd5\u5e94\u8be5\u662f\uff1a<br \/>\n\/<em>+ parallel(t 8) <\/em>\/\uff0c\/<em>+ index(t t_idx) <\/em>\/<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u662f\u4e00\u4e2a\u6bd4\u8f83\u4e0d\u5bb9\u6613\u53d1\u73b0\u7684\u95ee\u9898\u3002\u4e0b\u9762\u51e0\u6761SQL\uff0c\u54ea\u4e00\u6761<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[17],"tags":[],"class_list":["post-1399","post","type-post","status-publish","format-standard","hentry","category-oracle-10g"],"_links":{"self":[{"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/posts\/1399","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.821121.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1399"}],"version-history":[{"count":1,"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/posts\/1399\/revisions"}],"predecessor-version":[{"id":1402,"href":"http:\/\/www.821121.com\/index.php?rest_route=\/wp\/v2\/posts\/1399\/revisions\/1402"}],"wp:attachment":[{"href":"http:\/\/www.821121.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1399"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.821121.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1399"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.821121.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1399"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}