本例以hive为例,只考虑到实现,与性能无关
首先创建表
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CREATE TABLE orders ( orderid INT , createtime STRING, modifiedtime STRING, status STRING ) row format delimited fields terminated by '/t' CREATE TABLE ods_orders_inc ( orderid INT , createtime STRING, modifiedtime STRING, status STRING ) PARTITIONED BY ( day STRING) row format delimited fields terminated by '/t' CREATE TABLE dw_orders_his ( orderid INT , createtime STRING, modifiedtime STRING, status STRING, dw_start_date STRING, dw_end_date STRING ) row format delimited fields terminated by '/t' ; |
首先全量更新,我们先到2016-08-20为止的数据。
初始化,先把2016-08-20的数据初始化进去
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INSERT overwrite TABLE ods_orders_inc PARTITION ( day = '2016-08-20' ) SELECT orderid,createtime,modifiedtime,status FROM orders WHERE createtime < '2016-08-21' and modifiedtime < '2016-08-21' ; |
刷到dw中
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INSERT overwrite TABLE dw_orders_his SELECT orderid,createtime,modifiedtime,status, createtime AS dw_start_date, '9999-12-31' AS dw_end_date FROM ods_orders_inc WHERE day = '2016-08-20' ; |
如下结果
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select * from dw_orders_his; OK 1 2016-08-20 2016-08-20 创建 2016-08-20 9999-12-31 2 2016-08-20 2016-08-20 创建 2016-08-20 9999-12-31 3 2016-08-20 2016-08-20 创建 2016-08-20 9999-12-31 |
原创文章,作者:carmelaweatherly,如若转载,请注明出处:https://blog.ytso.com/194326.html