Hi,
I'm looking for an example of the constraints in HBase with |void check
(put p)|, this is indeed possible, but how? Does anyone possible
examples (code) to?
Ever advance thank you!
best regards!
Am 18.02.2013 01:15, schrieb Andrew Purtell:
> 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]
> <mailto:[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]
> <mailto:[EMAIL PROTECTED]>> wrote:
>
> > bcc: asynchbase@
> >
> > On Sat, Feb 16, 2013 at 12:28 PM, Steve Berg
> <[EMAIL PROTECTED] <mailto:[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)