HBase为Scala/Java API中的同一行键存储具有2个或更多值的特定列的数据 [英] HBase storing data for a particular column with 2 or more values for the same row-key in Scala/Java API

问题描述

我有一个包含以下内容的文件:

I have a file with following contents:

UserID   Email             
1001     [e-mail]     
1001     [e-mail]     
1002     [e-mail]
1002     [e-mail]

我想这样存储数据:

ROW          COLUMN+CELL                                                                                   
1001         column=cf:Email, timestamp=1487917201278, value=[e-mail] 
1001         column=cf:Email, timestamp=1487917201279, value=[e-mail]                                                                                                
1002         column=cf:Email, timestamp=1487917201286, value=[e-mail]
1002         column=cf:Email, timestamp=1487917201287, value=[e-mail]

我正在使用Put例如:put 'table', '1001', 'cf:Email', '[e-mail]'，但它给了我

I am using Put for example: put 'table', '1001', 'cf:Email', '[e-mail]' but it is giving me

ROW          COLUMN+CELL                                                                                    
1001         column=cf:Email, timestamp=1487917201279, value=[e-mail]                                                                                                
1002         column=cf:Email, timestamp=1487917201286, value=[e-mail]

它覆盖了先前的值.但是HBase应该基于时间戳存储特定列的多个值. 无论如何，我可以为特定的UserID存储两个电子邮件地址吗?

It is overriding the previous value. But HBase supposed to store multiple values for a particular column based on timestamp. Is there anyway that I can store both email addresses for particular UserID?

推荐答案

您可能需要仔细看看

You may want to take a closer look at the HBase documentation on versions. Note especially where it says

默认情况下，即，如果您未指定任何显式版本，则在执行get时，将返回其版本值最大的单元格

By default, i.e. if you specify no explicit version, when doing a get, the cell whose version has the largest value is returned

但是我不会追求使用多个版本以这种方式存储多个值.您必须明确指定最大版本数，并将其应用于该系列中的每一列.我会更倾向于使用不同的列名(例如Email1，Email2，...)

But I wouldn't pursue using multiple versions to store multiple values this way. You have to explicitly specify the maximum number of versions and it will apply to every column in that family. I would be more inclined to use distinct column names (such as Email1, Email2, ...)

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