{"id":8047,"date":"2021-09-22T09:30:53","date_gmt":"2021-09-22T01:30:53","guid":{"rendered":"https:\/\/www.gbase8.cn\/?p=8047"},"modified":"2021-09-22T09:30:53","modified_gmt":"2021-09-22T01:30:53","slug":"gbase-8a%e5%90%84%e7%a7%8djoin%e7%9a%84%e4%b8%8d%e5%90%8c%ef%bc%8cleft-right-inner-full-outer%e7%ad%89%e6%a0%b7%e4%be%8b","status":"publish","type":"post","link":"https:\/\/www.gbase8.cn\/en\/8047","title":{"rendered":"\u5357\u5927\u901a\u7528GBase 8a\u5404\u79cdjoin\u7684\u4e0d\u540c\uff0cleft right inner full outer\u7b49\u6837\u4f8b"},"content":{"rendered":"<p>\u672c\u6587\u901a\u8fc7GBase 8a \u4ecb\u7ecd\u5404\u79cdJOIN\u7684\u4e0d\u540c\uff0c\u5305\u62ecinner join, left join, right join, full outer join, \u5206\u522b\u5bf9\u5e94\u5185\u8fde\u63a5\uff0c\u5de6\u5916\u8fde\u63a5\uff0c\u53f3\u5916\u8fde\u63a5\uff0c\u548c\u5168\u5916\u8fde\u63a5\u3002<\/p>\n\n\n\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_84 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Directory Navigation<\/p>\n<label for=\"ez-toc-cssicon-toggle-item-6a2b1ef1ccb9a\" class=\"ez-toc-cssicon-toggle-label\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewbox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewbox=\"0 0 24 24\" version=\"1.2\" baseprofile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input type=\"checkbox\"  id=\"ez-toc-cssicon-toggle-item-6a2b1ef1ccb9a\"  aria-label=\"Toggle\" \/><nav><ul class='ez-toc-list ez-toc-list-level-1' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.gbase8.cn\/en\/8047\/#%E6%80%BB%E7%BB%93\" >Summary<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.gbase8.cn\/en\/8047\/#%E6%95%B0%E6%8D%AE\" >\u6570\u636e<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.gbase8.cn\/en\/8047\/#A%E8%A1%A8\" >A\u8868<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.gbase8.cn\/en\/8047\/#B%E8%A1%A8\" >B\u8868<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.gbase8.cn\/en\/8047\/#inner_join\" >inner join<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.gbase8.cn\/en\/8047\/#left_join\" >left join<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.gbase8.cn\/en\/8047\/#right_join\" >right join<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.gbase8.cn\/en\/8047\/#full_outer_join\" >full outer join<\/a><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E6%80%BB%E7%BB%93\"><\/span>Summary<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>\u4ee5A \u3001B\u4e24\u4e2a\u8868\u4e3a\u4f8b\uff0c<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>A inner join B \u662f\u5fc5\u987bA\u5b58\u5728\uff0cB\u4e5f\u5b58\u5728<\/li><li>A left join B \u662fA\u5fc5\u987b\u5b58\u5728\uff0cB\u4e0d\u4e00\u5b9a\u5b58\u5728\uff0c\u5339\u914d\u4e0d\u4e0a\u5c31\u662fnull<\/li><li>A right B \u662fB\u5fc5\u987b\u5b58\u5728\uff0cA\u4e0d\u4e00\u5b9a\u5b58\u5728\uff0c\u5339\u914d\u4e0d\u4e0a\u5c31\u662fnull<\/li><li>A full outer join B, \u662fleft \u548c right \u7684\u5408\u96c6\uff0c \u6709A\u53ef\u4ee5\u6ca1\u6709B, \u5728\u52a0\u4e0a\u6709B\u53ef\u4ee5\u6ca1\u6709A<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E6%95%B0%E6%8D%AE\"><\/span>\u6570\u636e<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>A\u662f\u4e8b\u5b9e\u8868\uff0cB\u662f\u7ef4\u5ea6\u8868\uff0cB\u91cc\u6ca1\u6709\u91cd\u590d\u6570\u636e\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"A%E8%A1%A8\"><\/span>A\u8868<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>\u4e8b\u5b9e\u660e\u7ec6\u8868\uff0c\u91cc\u9762\u7684bid \u5bf9\u5e94\u7740B\u8868\u300210\u884c\u91cc\u67094\u884c\u5728B\u91cc\u4e0d\u5b58\u5728\u7684\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>gbase> select * from A;\r\n+------+------+\r\n| id   | bid  |\r\n+------+------+\r\n|    1 |    1 |\r\n|    2 |    1 |\r\n|    3 |    1 |\r\n|    4 |    2 |\r\n|    5 |    2 |\r\n|    6 |    3 |\r\n|    7 |   66 |\r\n|    8 |   77 |\r\n|    9 |   88 |\r\n|   10 |   99 |\r\n+------+------+\r\n10 rows in set (Elapsed: 00:00:00.01)\r\n<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"B%E8%A1%A8\"><\/span>B\u8868<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>\u7ef4\u5ea6\u8868\uff0c5\u884c\u91cc\uff0c\u67092\u884c\u5728\u660e\u7ec6\u8868\u91cc\u6ca1\u7528\u5230\u7684\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>gbase> select * from B;\r\n+------+\r\n| id   |\r\n+------+\r\n|    1 |\r\n|    2 |\r\n|    3 |\r\n|    4 |\r\n|    5 |\r\n+------+\r\n5 rows in set (Elapsed: 00:00:00.00)\r\n<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"inner_join\"><\/span>inner join<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>A\u91cc\u5b58\u5728\u4e14B\u91cc\u4e5f\u5b58\u5728\uff0c\u6240\u4ee5\u9884\u671f\u7ed3\u679c\u662fA\u91cc6\u884c\u7ed3\u679c\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>gbase> select * from A inner join B on A.bid=b.id;\r\n+------+------+------+\r\n| id   | bid  | id   |\r\n+------+------+------+\r\n|    1 |    1 |    1 |\r\n|    2 |    1 |    1 |\r\n|    3 |    1 |    1 |\r\n|    4 |    2 |    2 |\r\n|    5 |    2 |    2 |\r\n|    6 |    3 |    3 |\r\n+------+------+------+\r\n6 rows in set (Elapsed: 00:00:00.04)\n<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"left_join\"><\/span>left join<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>A\u91cc\u5b58\u5728\uff0cB\u53ef\u4ee5\u6ca1\u6709\u5339\u914d\u4e0a\uff0c\u7ed3\u679c\u5c31\u662fA\u768410\u884c\uff0c\u5176\u4e2d6\u884c\u5339\u914d\u4e0a\u4e86\uff0c4\u884c\u6ca1\u6709\u5339\u914d\u4e0a\uff0c\u4e3aNULL.<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>gbase> select * from A left join B on A.bid=b.id;\r\n+------+------+------+\r\n| id   | bid  | id   |\r\n+------+------+------+\r\n|    1 |    1 |    1 |\r\n|    2 |    1 |    1 |\r\n|    3 |    1 |    1 |\r\n|    4 |    2 |    2 |\r\n|    5 |    2 |    2 |\r\n|    6 |    3 |    3 |\r\n|    7 |   66 | NULL |\r\n|    8 |   77 | NULL |\r\n|    9 |   88 | NULL |\r\n|   10 |   99 | NULL |\r\n+------+------+------+\r\n10 rows in set (Elapsed: 00:00:00.04)\r\n<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"right_join\"><\/span>right join<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>B\u5fc5\u987b\u5b58\u5728\uff0cA\u53ef\u4ee5\u6ca1\u6709\u5339\u914d\u4e0a\uff0c\u7ed3\u679cB\u7684\u524d3\u4e2aid\uff0c\u5339\u914d\u4e0a\u4e86A\u8868\u76846\u884c\uff0c B\u8fd8\u67092\u884c\u6ca1\u6709A\u5339\u914d\uff0c\u7d2f\u8ba16+2=8\u884c\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>gbase> select * from A right join B on A.bid=b.id;\r\n+------+------+------+\r\n| id   | bid  | id   |\r\n+------+------+------+\r\n|    1 |    1 |    1 |\r\n|    2 |    1 |    1 |\r\n|    3 |    1 |    1 |\r\n|    4 |    2 |    2 |\r\n|    5 |    2 |    2 |\r\n|    6 |    3 |    3 |\r\n| NULL | NULL |    4 |\r\n| NULL | NULL |    5 |\r\n+------+------+------+\r\n8 rows in set (Elapsed: 00:00:00.03)\r\n<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"full_outer_join\"><\/span>full outer join<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>left\u548cright\u7684\u5408\u96c6\uff0c \u90fd\u5339\u914d\u76846\u884c\uff0c A left B\u6ca1\u6709\u5339\u914d\u4e0a\u76844\u884c\uff0c A right B \u6ca1\u6709\u5339\u914d\u4e0a\u76842\u884c\uff0c\u4e00\u5171 6+4+2=12\u884c\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>gbase> select * from A full outer join B on A.bid=b.id;\r\n+------+------+------+\r\n| id   | bid  | id   |\r\n+------+------+------+\r\n|    1 |    1 |    1 |\r\n|    2 |    1 |    1 |\r\n|    3 |    1 |    1 |\r\n|    4 |    2 |    2 |\r\n|    5 |    2 |    2 |\r\n|    6 |    3 |    3 |\r\n| NULL | NULL |    4 |\r\n| NULL | NULL |    5 |\r\n|    7 |   66 | NULL |\r\n|    8 |   77 | NULL |\r\n|    9 |   88 | NULL |\r\n|   10 |   99 | NULL |\r\n+------+------+------+\r\n12 rows in set (Elapsed: 00:00:00.04)\r\n<\/code><\/pre>\n\n\n\n<p><\/p>","protected":false},"excerpt":{"rendered":"<p>\u672c\u6587\u901a\u8fc7GBase 8a \u4ecb\u7ecd\u5404\u79cdJOIN\u7684\u4e0d\u540c\uff0c\u5305\u62ecinner join, left join, right join, full outer join, \u5206\u522b\u5bf9\u5e94\u5185\u8fde\u63a5\uff0c\u5de6\u5916\u8fde\u63a5\uff0c\u53f3\u5916\u8fde\u63a5\uff0c\u548c\u5168\u5916\u8fde\u63a5\u3002<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[],"class_list":["post-8047","post","type-post","status-publish","format-standard","hentry","category-gbase8a"],"_links":{"self":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/8047","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/comments?post=8047"}],"version-history":[{"count":1,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/8047\/revisions"}],"predecessor-version":[{"id":8048,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/8047\/revisions\/8048"}],"wp:attachment":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/media?parent=8047"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/categories?post=8047"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/tags?post=8047"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}