question Re: how hive can read Hbase current and previous versions data? in Archives of Support Questions (Read Only)

how hive can read Hbase current and previous versions data?

subhrajit — Wed, 04 May 2016 16:14:16 GMT

Re: how hive can read Hbase current and previous versions data?

pminovic — Wed, 04 May 2016 16:21:15 GMT

As far as I know, Hive can read only the current (most recent) data version in HBase. Only when using HBase API or hbase shell you can also read all versions, or only the ones in a specific time interval.

From the Hive HBase integration document: there is currently no way to access the HBase timestamp attribute, and queries always access data with the latest timestamp.

Re: how hive can read Hbase current and previous versions data?

rajkumar_singh — Wed, 04 May 2016 16:26:52 GMT

currently there is no way available to read all the versions data.

Re: how hive can read Hbase current and previous versions data?

subhrajit — Thu, 05 May 2016 12:58:30 GMT

Thanks for replying.

if not hive can impala read all versions in HBase?

Re: how hive can read Hbase current and previous versions data?

pminovic — Thu, 05 May 2016 14:58:59 GMT

No, Impala cannot read all versions either. Impala defines tables in HBase using Hive DDL because Impala doesn't support custom SerDe's to define tables, and as we saw Hive doesn't expose HBase timestamps (more detail about Impala and HBase here). So, if you want to access timestamps you have to make them "first class citizens" and include them in your Hbase table key, or among values, if you can ensure unique keys by other means.

Re: how hive can read Hbase current and previous versions data?

subhrajit — Mon, 09 May 2016 13:19:37 GMT

thank you 🙂

Re: how hive can read Hbase current and previous versions data?

pminovic — Mon, 09 May 2016 14:17:24 GMT

Okay, no problems, please consider to accept the answer, to help us manage answered questions. Tnx!