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From Shushant Arora <shushantaror...@gmail.com>
Subject Re: hbase doubts
Date Mon, 17 Aug 2015 16:41:13 GMT
~8-10 fields of size (5 of  20 bytes each )and 3 fields of size 200 bytes
each.

On Mon, Aug 17, 2015 at 9:55 PM, Ted Yu <yuzhihong@gmail.com> wrote:

> How many fields such as F1 are you considering for embedding in row key ?
>
> Suggested reading:
> http://hbase.apache.org/book.html#rowkey.design
> http://hbase.apache.org/book.html#client.filter.kvm (see
> ColumnPrefixFilter)
>
> Cheers
>
> On Mon, Aug 17, 2015 at 8:13 AM, Shushant Arora <shushantarora09@gmail.com
> >
> wrote:
>
> > 1.so size limit is per cell's identifier + value ?
> >
> > What is more optimise - to have field in key or in column family's
> column ?
> > If pattern is like every row has that field.
> >
> > Say I have a field F1 in all rows so
> > Situtatio -1
> > key1#F1(as composite key)  - and rest fields in column
> >
> > Situation-2
> > key1 as key and F1 part of column family.
> >
> >
> > This is the main reason I  asked the key size limit.
> > If I asked for no of rows where F1 is = 'someval' will it be faster in
> > situation-1 than in situation-2. Since in 1 it can return the result just
> > by traversing keys no need to read columns?
> >
> >
> > On Mon, Aug 17, 2015 at 8:27 PM, Ted Yu <yuzhihong@gmail.com> wrote:
> >
> > > For #1, it is the limit on a single keyvalue, not row, not key.
> > >
> > > For #2, please see the following:
> > >
> > > http://hbase.apache.org/book.html#store.memstore
> > >
> http://hbase.apache.org/book.html#regionserver_splitting_implementation
> > >
> > > Cheers
> > >
> > > On Mon, Aug 17, 2015 at 7:36 AM, Shushant Arora <
> > shushantarora09@gmail.com
> > > >
> > > wrote:
> > >
> > > > 1.Is hbase.client.keyvalue.maxsize  is max size of row or key only ?
> Is
> > > > there any limit on key size only ?
> > > > 2.Access pattern is mostly on key based only- Is memstores and
> regions
> > > on a
> > > > regionserver are per table basis? Is it if I have multiple tables it
> > will
> > > > have multiple memstores instead of few if it would have been one
> large
> > > > table ?
> > > >
> > > >
> > > > On Mon, Aug 17, 2015 at 7:29 PM, Ted Yu <yuzhihong@gmail.com> wrote:
> > > >
> > > > > For #1, take a look at the following in hbase-default.xml :
> > > > >
> > > > >     <name>hbase.client.keyvalue.maxsize</name>
> > > > >     <value>10485760</value>
> > > > >
> > > > > For #2, it would be easier to answer if you can outline access
> > patterns
> > > > in
> > > > > your app.
> > > > >
> > > > > For #3, adjustment according to current region boundaries is done
> > > client
> > > > > side. Take a look at the javadoc for LoadQueueItem
> > > > > in LoadIncrementalHFiles.java
> > > > >
> > > > > Cheers
> > > > >
> > > > > On Mon, Aug 17, 2015 at 6:45 AM, Shushant Arora <
> > > > shushantarora09@gmail.com
> > > > > >
> > > > > wrote:
> > > > >
> > > > > > 1.Is there any max limit on key size of hbase table.
> > > > > > 2.Is multiple small tables vs one large table which one is
> > preferred.
> > > > > > 3.for bulk load -when  LoadIncremantalHfile is run it again
> > > > recalculates
> > > > > > the region splits based on region boundary - is this division
> > happens
> > > > on
> > > > > > client side or server side again at region server or hbase master
> > and
> > > > > then
> > > > > > it assigns the splits which cross target region boundary to
> desired
> > > > > > regionserver.
> > > > > >
> > > > >
> > > >
> > >
> >
>

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