Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
HBase >> mail # user >> Re: HBase and Data Integrity


Copy link to this message
-
Re: HBase and Data Integrity
Yes, but implementing a constraint requires implementing a coprocessor,
which is not something I'd recommend to users as a general practice. HBase
doesn't offer referential integrity as commonly understood in the RDBMS
world (foreign keys, etc.) out of the box.
On Sat, Feb 16, 2013 at 6:52 PM, Ted Yu <[EMAIL PROTECTED]> wrote:

> Some addendum to Benoit's answers.
> In HBase you can setup Constraint for your table. From javadoc:
>
>  * Apply a {@link Constraint} (in traditional database terminology) to a
> HTable.
>
>  * Any number of {@link Constraint Constraints} can be added to the table,
> in
>
>  * any order.
> See
> hbase-server/src/main/java/org/apache/hadoop/hbase/constraint/Constraint.java
>
> Cheers
>
> On Sat, Feb 16, 2013 at 4:48 PM, tsuna <[EMAIL PROTECTED]> wrote:
>
> > bcc: asynchbase@
> >
> > On Sat, Feb 16, 2013 at 12:28 PM, Steve Berg <[EMAIL PROTECTED]>
> > wrote:
> > > I have some questions for HBase DB:
> >
> > Hi Steve,
> > I'm moving this thread to the HBase user mailing list.
> >
> > > How to ensure data integrity?
> >
> > Data stored by HBase in HDFS has 3 replicas of the data and checksums.
> >
> > > Are there methods ensure the integrity?
> >
> > It's all built-in, I'm not sure what you meant by "methods" here.
> >
> > > Does HBase primary key? or alternatives
> >
> > HBase has only one primary key per table.
> > You may wanna look at the HBase Book, Chapter 5. "Data Model":
> > http://hbase.apache.org/book.html#datamodel
> >
> > > Foreign key?
> >
> > No.
> >
> > > Referential Integrity?
> >
> > No.
> >
> > > How are the ACID properties to be implemented?
> >
> > http://hbase.apache.org/acid-semantics.html
> >
> > --
> > Benoit "tsuna" Sigoure
> >
>

--
Best regards,

   - Andy

Problems worthy of attack prove their worth by hitting back. - Piet Hein
(via Tom White)