{"id":1811,"date":"2020-10-26T13:09:18","date_gmt":"2020-10-26T05:09:18","guid":{"rendered":"https:\/\/www.gbase8.cn\/?p=1811"},"modified":"2020-10-26T13:09:20","modified_gmt":"2020-10-26T05:09:20","slug":"gbase-8a%e5%8a%a0%e8%bd%bd%e9%80%9a%e8%bf%87null_value%e5%8f%82%e6%95%b0%e6%8c%87%e5%ae%9anull%e7%a9%ba%e5%80%bc%e7%9a%84%e5%8f%82%e6%95%b0","status":"publish","type":"post","link":"https:\/\/www.gbase8.cn\/en\/1811","title":{"rendered":"\u5357\u5927\u901a\u7528GBase 8a\u52a0\u8f7d\u901a\u8fc7null_value\u53c2\u6570\u6307\u5b9anull\u7a7a\u503c\u7684\u53c2\u6570"},"content":{"rendered":"<p>GBase 8a\u96c6\u7fa4\u6570\u636e\u5e93\uff0c\u901a\u8fc7load\u52a0\u8f7d\u65f6\uff0c\u9ed8\u8ba4\u7684\u6570\u636enull\u503c\u662f\\N\uff0c\u53ef\u4ee5\u901a\u8fc7null_value\u53c2\u6570\u6307\u5b9a\u7a7a\u503c\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-6a2aaa48482e4\" 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-6a2aaa48482e4\"  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\/1811\/#%E6%8F%90%E7%A4%BA\" >\u63d0\u793a<\/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\/1811\/#%E6%8C%87%E5%AE%9Anull%E4%B8%BA%E7%A9%BA%E5%80%BC\" >\u6307\u5b9anull\u4e3a\u7a7a\u503c<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.gbase8.cn\/en\/1811\/#%E6%8C%87%E5%AE%9A_N%E4%B8%BA%E7%A9%BA%E5%80%BC\" >\u6307\u5b9a \\N\u4e3a\u7a7a\u503c<\/a><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E6%8F%90%E7%A4%BA\"><\/span>\u63d0\u793a<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>null\u7a7a\u503c\uff0c\u548c\u7a7a\u5b57\u7b26\u4e32\uff0c\u5728GBase\u6570\u636e\u5e93\u5185\u662f\u533a\u5206, \u67e5\u8be2null\u9700\u8981\u7528 is null, \u800c\u7a7a\u5b57\u7b26\u4e32\u662f =''<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E6%8C%87%E5%AE%9Anull%E4%B8%BA%E7%A9%BA%E5%80%BC\"><\/span>\u6307\u5b9anull\u4e3a\u7a7a\u503c<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>\u5982\u4e0b\u751f\u6210\u4e00\u884c\u6570\u636e\uff0c\u5176\u4e2dname\u5b57\u6bb5\u662fnull \u8868\u793a\u7a7a\u503c. \u901a\u8fc7load\u8bed\u53e5\u7684null_value 'null' \u6307\u5b9a\u5b57\u7b26\u4e32 null \u4ee3\u8868\u7a7a\u503c\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>gbase> create table t1(id int, name varchar(100),birth date);\nQuery OK, 0 rows affected (Elapsed: 00:00:00.15)\n\ngbase> system echo \"1,null,2020-01-02\" > \/home\/gbase\/t1.txt\ngbase> load data infile 'sftp:\/\/gbase:gbase1234@10.0.2.102\/home\/gbase\/t1.txt' into table t1 null_value 'null' fields terminated by ',';\nQuery OK, 1 row affected (Elapsed: 00:00:01.28)\nTask 13 finished, Loaded 1 records, Skipped 0 records\n\ngbase> select * from t1;\n+------+------+------------+\n| id   | name | birth      |\n+------+------+------------+\n|    1 | NULL | 2020-01-02 |\n+------+------+------------+\n1 row in set (Elapsed: 00:00:00.01)\n\ngbase> select * from t1 where name is null;\n+------+------+------------+\n| id   | name | birth      |\n+------+------+------------+\n|    1 | NULL | 2020-01-02 |\n+------+------+------------+\n1 row in set (Elapsed: 00:00:00.01)\n<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E6%8C%87%E5%AE%9A_N%E4%B8%BA%E7%A9%BA%E5%80%BC\"><\/span>\u6307\u5b9a \\N\u4e3a\u7a7a\u503c<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>\u5982\u4e0b\u7528\\N\u751f\u6210\u4e00\u884c\u6570\u636e\uff0c\u5e76\u901a\u8fc7 null_value='\\\\N' \u6765\u52a0\u8f7d\u3002\u6ce8\u610f\\\u662f\u8f6c\u4e49\u7b26\uff0c\u6240\u4ee5\u9700\u8981\u7528\\\\\u6765\u4ee3\u8868\\, \u5426\u5219\u4f1a\u5c06\u539f\u59cb\u6570\u636e\\N\u76f4\u63a5\u52a0\u8f7d\u5230\u6570\u636e\u5e93\u5185\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>gbase> system echo \"2,\\N,2020-03-04\" > \/home\/gbase\/t1.txt\ngbase> system cat \/home\/gbase\/t1.txt\n2,\\N,2020-03-04\n\ngbase> load data infile 'sftp:\/\/gbase:gbase1234@10.0.2.102\/home\/gbase\/t1.txt' into table t1  fields terminated by ',';\nQuery OK, 1 row affected (Elapsed: 00:00:01.56)\nTask 14 finished, Loaded 1 records, Skipped 0 records\n\ngbase> select * from t1 where name is null;\n+------+------+------------+\n| id   | name | birth      |\n+------+------+------------+\n|    1 | NULL | 2020-01-02 |\n+------+------+------------+\n1 row in set (Elapsed: 00:00:00.00)\n\ngbase> select * from t1;\n+------+------+------------+\n| id   | name | birth      |\n+------+------+------------+\n|    1 | NULL | 2020-01-02 |\n|    2 | \\N   | 2020-03-04 |\n+------+------+------------+\n2 rows in set (Elapsed: 00:00:00.01)\n\ngbase> load data infile 'sftp:\/\/gbase:gbase1234@10.0.2.102\/home\/gbase\/t1.txt' into table t1 null_value '\\N' fields terminated by ',';\nQuery OK, 1 row affected (Elapsed: 00:00:01.19)\nTask 15 finished, Loaded 1 records, Skipped 0 records\n\ngbase> select * from t1;\n+------+------+------------+\n| id   | name | birth      |\n+------+------+------------+\n|    1 | NULL | 2020-01-02 |\n|    2 | \\N   | 2020-03-04 |\n|    2 | \\N   | 2020-03-04 |\n+------+------+------------+\n3 rows in set (Elapsed: 00:00:00.00)\n\ngbase> load data infile 'sftp:\/\/gbase:gbase1234@10.0.2.102\/home\/gbase\/t1.txt' into table t1 null_value '\\\\N' fields terminated by ',';\nQuery OK, 1 row affected (Elapsed: 00:00:01.40)\nTask 16 finished, Loaded 1 records, Skipped 0 records\n\ngbase> select * from t1;\n+------+------+------------+\n| id   | name | birth      |\n+------+------+------------+\n|    1 | NULL | 2020-01-02 |\n|    2 | \\N   | 2020-03-04 |\n|    2 | \\N   | 2020-03-04 |\n|    2 | NULL | 2020-03-04 |\n+------+------+------------+\n4 rows in set (Elapsed: 00:00:00.01)\n\ngbase> select * from t1 where name is null;\n+------+------+------------+\n| id   | name | birth      |\n+------+------+------------+\n|    1 | NULL | 2020-01-02 |\n|    2 | NULL | 2020-03-04 |\n+------+------+------------+\n2 rows in set (Elapsed: 00:00:00.01)\n\n<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-embed-wordpress wp-block-embed is-type-wp-embed is-provider-\u8001\u7d2b\u7af9\u7684\u5bb6\"><div class=\"wp-block-embed__wrapper\">\n<blockquote class=\"wp-embedded-content\" data-secret=\"AxyymzxdbB\"><a href=\"https:\/\/www.gbase8.cn\/en\/121\/\">GBase 8a \u96c6\u7fa4\u52a0\u8f7d\u6570\u636eLOAD\u7684\u65b9\u6cd5<\/a><\/blockquote><iframe loading=\"lazy\" class=\"wp-embedded-content\" sandbox=\"allow-scripts\" security=\"restricted\" style=\"position: absolute; clip: rect(1px, 1px, 1px, 1px);\" title=\"\u300aGBase 8a \u96c6\u7fa4\u52a0\u8f7d\u6570\u636eLOAD\u7684\u65b9\u6cd5\u300b\u2014\u8001\u7d2b\u7af9\u7684\u5bb6\" src=\"https:\/\/www.gbase8.cn\/121\/embed#?secret=AxyymzxdbB\" data-secret=\"AxyymzxdbB\" width=\"600\" height=\"338\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe>\n<\/div><\/figure>","protected":false},"excerpt":{"rendered":"<p>8a\u52a0\u8f7d\u901a\u8fc7null_value\u53c2\u6570\u6307\u5b9anull\u7a7a\u503c\u7684\u53c2\u6570<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[10],"class_list":["post-1811","post","type-post","status-publish","format-standard","hentry","category-gbase8a","tag-10"],"_links":{"self":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/1811","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=1811"}],"version-history":[{"count":2,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/1811\/revisions"}],"predecessor-version":[{"id":2112,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/1811\/revisions\/2112"}],"wp:attachment":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/media?parent=1811"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/categories?post=1811"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/tags?post=1811"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}