You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@hbase.apache.org by Ted Yu <yu...@gmail.com> on 2010/11/15 23:02:33 UTC
Re: retrieving timestamp from Result
We used the following code to see if the "Cell" (pardon me for using the old
term) returned from scanner was of certain timestamp:
if (result.getCellValue().getTimestamp() == ts){
In 0.90, I don't see method which returns the timestamp for Result.
I am wondering if the above check can be omitted since we specify the
following for the Scan:
scan.setTimeStamp(ts);
If not, please advise the correct way of retrieving timestamp from Result.
If I call Result.raw() and get two KeyValue's, which should be the KeyValue
whose timestamp conforms to the semantics of our check shown at the top ?
Thanks
On Mon, Nov 15, 2010 at 12:38 PM, Ryan Rawson <ry...@gmail.com> wrote:
> That is correct, those classes were deprecated in 0.20, and now gone in
> 0.90.
>
> Now you will want to use HTable and Result.
>
> Also Filter.getNextKeyHint() is an implementation detail, have a look
> at the other filters to get a sense of what it does.
>
> On Mon, Nov 15, 2010 at 12:33 PM, Ted Yu <yu...@gmail.com> wrote:
> > Just a few findings when I tried to compile our 0.20.6 based code with
> this
> > new release:
> >
> > HConstants is final class now instead of interface
> > RowFilterInterface is gone
> > org.apache.hadoop.hbase.io.Cell is gone
> > org.apache.hadoop.hbase.io.RowResult is gone
> > constructor
> >
> HColumnDescriptor(byte[],int,java.lang.String,boolean,boolean,int,boolean)
> > is gone
> > Put.setTimeStamp() is gone
> > org.apache.hadoop.hbase.filter.Filter has added
> > getNextKeyHint(org.apache.hadoop.hbase.KeyValue)
> >
> > If you know the alternative to some of the old classes, please share.
> >
> > On Mon, Nov 15, 2010 at 2:51 AM, Stack <st...@duboce.net> wrote:
> >
> >> The first hbase 0.90.0 release candidate is available for download:
> >>
> >> http://people.apache.org/~stack/hbase-0.90.0-candidate-0/<http://people.apache.org/%7Estack/hbase-0.90.0-candidate-0/>
> <http://people.apache.org/%7Estack/hbase-0.90.0-candidate-0/>
> >>
> >> HBase 0.90.0 is the major HBase release that follows 0.20.0 and the
> >> fruit of the 0.89.x development release series we've been running of
> >> late.
> >>
> >> More than 920 issues have been closed since 0.20.0. Release notes are
> >> available here: http://su.pr/8LbgvK.
> >>
> >> HBase 0.90.0 runs on Hadoop 0.20.x. It does not currently run on
> >> Hadoop 0.21.0. HBase will lose data unless it is running on an
> >> Hadoop HDFS 0.20.x that has a durable sync. Currently only the
> >> branch-0.20-append branch [1] has this attribute. No official releases
> >> have been made from this branch as yet so you will have to build your
> >> own Hadoop from the tip of this branch or install Cloudera's CDH3 [2]
> >> (Its currently in beta). CDH3b2 or CDHb3 have the 0.20-append patches
> >> needed to add a durable sync. See CHANGES.txt [3] in
> >> branch-0.20-append to see list of patches involved.
> >>
> >> There is no migration necessary. Your data written with HBase 0.20.x
> >> (or with HBase 0.89.x) is readable by HBase 0.90.0. A shutdown and
> >> restart after putting in place the new HBase should be all thats
> >> involved. That said, once done, there is no going back to 0.20.x once
> >> the transition has been made. HBase 0.90.0 and HBase 0.89.x write
> >> region names differently in the filesystem. Rolling restart from
> >> 0.20.x or 0.89.x to 0.90.0RC0 will not work.
> >>
> >> Should we release this candidate as hbase 0.90.0? Take it for a spin.
> >> Check out the doc. Vote +1/-1 by November 22nd.
> >>
> >> Yours,
> >> The HBasistas
> >> P.S. For why the version 0.90 and whats new in HBase 0.90, see slides
> >> 4-10 in this deck [4]
> >>
> >> 1.
> http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-append
> >> 2. http://archive.cloudera.com/docs/
> >> 3.
> >>
> http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-append/CHANGES.txt
> >> 4. http://hbaseblog.com/2010/07/04/hug11-hbase-0-90-preview-wrap-up/
> >>
> >
>
Re: retrieving timestamp from Result
Posted by Ryan Rawson <ry...@gmail.com>.
Within a "Result" object you are only going to get columns for a
single row. So the 2 byte[] are family and qualifier. Check the
javadoc. I wrote quite a bit of documentation on these APIs.
Thanks,
-ryan
On Mon, Nov 15, 2010 at 3:42 PM, Ted Yu <yu...@gmail.com> wrote:
> Since there may be more than one qualifier for a column family, is it
> reasonable to add Result.getColumnLatest(byte[]) which returns the latest
> column for given family ?
>
> Thanks
>
> On Mon, Nov 15, 2010 at 2:12 PM, Ryan Rawson <ry...@gmail.com> wrote:
>
>> The javadoc details what to expect.
>>
>> You can also call Result.getColumnLatest(byte[],byte[])
>>
>> The resulting KeyValue has methods like getTimestamp() etc.
>>
>> -ryan
>>
>>
>> On Mon, Nov 15, 2010 at 2:02 PM, Ted Yu <yu...@gmail.com> wrote:
>> > We used the following code to see if the "Cell" (pardon me for using the
>> old
>> > term) returned from scanner was of certain timestamp:
>> > if (result.getCellValue().getTimestamp() == ts){
>> >
>> > In 0.90, I don't see method which returns the timestamp for Result.
>> > I am wondering if the above check can be omitted since we specify the
>> > following for the Scan:
>> > scan.setTimeStamp(ts);
>> > If not, please advise the correct way of retrieving timestamp from
>> Result.
>> >
>> > If I call Result.raw() and get two KeyValue's, which should be the
>> KeyValue
>> > whose timestamp conforms to the semantics of our check shown at the top ?
>> >
>> > Thanks
>> >
>> > On Mon, Nov 15, 2010 at 12:38 PM, Ryan Rawson <ry...@gmail.com>
>> wrote:
>> >
>> >> That is correct, those classes were deprecated in 0.20, and now gone in
>> >> 0.90.
>> >>
>> >> Now you will want to use HTable and Result.
>> >>
>> >> Also Filter.getNextKeyHint() is an implementation detail, have a look
>> >> at the other filters to get a sense of what it does.
>> >>
>> >> On Mon, Nov 15, 2010 at 12:33 PM, Ted Yu <yu...@gmail.com> wrote:
>> >> > Just a few findings when I tried to compile our 0.20.6 based code with
>> >> this
>> >> > new release:
>> >> >
>> >> > HConstants is final class now instead of interface
>> >> > RowFilterInterface is gone
>> >> > org.apache.hadoop.hbase.io.Cell is gone
>> >> > org.apache.hadoop.hbase.io.RowResult is gone
>> >> > constructor
>> >> >
>> >>
>> HColumnDescriptor(byte[],int,java.lang.String,boolean,boolean,int,boolean)
>> >> > is gone
>> >> > Put.setTimeStamp() is gone
>> >> > org.apache.hadoop.hbase.filter.Filter has added
>> >> > getNextKeyHint(org.apache.hadoop.hbase.KeyValue)
>> >> >
>> >> > If you know the alternative to some of the old classes, please share.
>> >> >
>> >> > On Mon, Nov 15, 2010 at 2:51 AM, Stack <st...@duboce.net> wrote:
>> >> >
>> >> >> The first hbase 0.90.0 release candidate is available for download:
>> >> >>
>> >> >> http://people.apache.org/~stack/hbase-0.90.0-candidate-0/<http://people.apache.org/%7Estack/hbase-0.90.0-candidate-0/>
>> <http://people.apache.org/%7Estack/hbase-0.90.0-candidate-0/>
>> >> <http://people.apache.org/%7Estack/hbase-0.90.0-candidate-0/>
>> >> >>
>> >> >> HBase 0.90.0 is the major HBase release that follows 0.20.0 and the
>> >> >> fruit of the 0.89.x development release series we've been running of
>> >> >> late.
>> >> >>
>> >> >> More than 920 issues have been closed since 0.20.0. Release notes
>> are
>> >> >> available here: http://su.pr/8LbgvK.
>> >> >>
>> >> >> HBase 0.90.0 runs on Hadoop 0.20.x. It does not currently run on
>> >> >> Hadoop 0.21.0. HBase will lose data unless it is running on an
>> >> >> Hadoop HDFS 0.20.x that has a durable sync. Currently only the
>> >> >> branch-0.20-append branch [1] has this attribute. No official
>> releases
>> >> >> have been made from this branch as yet so you will have to build your
>> >> >> own Hadoop from the tip of this branch or install Cloudera's CDH3 [2]
>> >> >> (Its currently in beta). CDH3b2 or CDHb3 have the 0.20-append
>> patches
>> >> >> needed to add a durable sync. See CHANGES.txt [3] in
>> >> >> branch-0.20-append to see list of patches involved.
>> >> >>
>> >> >> There is no migration necessary. Your data written with HBase 0.20.x
>> >> >> (or with HBase 0.89.x) is readable by HBase 0.90.0. A shutdown and
>> >> >> restart after putting in place the new HBase should be all thats
>> >> >> involved. That said, once done, there is no going back to 0.20.x
>> once
>> >> >> the transition has been made. HBase 0.90.0 and HBase 0.89.x write
>> >> >> region names differently in the filesystem. Rolling restart from
>> >> >> 0.20.x or 0.89.x to 0.90.0RC0 will not work.
>> >> >>
>> >> >> Should we release this candidate as hbase 0.90.0? Take it for a
>> spin.
>> >> >> Check out the doc. Vote +1/-1 by November 22nd.
>> >> >>
>> >> >> Yours,
>> >> >> The HBasistas
>> >> >> P.S. For why the version 0.90 and whats new in HBase 0.90, see slides
>> >> >> 4-10 in this deck [4]
>> >> >>
>> >> >> 1.
>> >> http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-append
>> >> >> 2. http://archive.cloudera.com/docs/
>> >> >> 3.
>> >> >>
>> >>
>> http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-append/CHANGES.txt
>> >> >> 4. http://hbaseblog.com/2010/07/04/hug11-hbase-0-90-preview-wrap-up/
>> >> >>
>> >> >
>> >>
>> >
>>
>
Re: retrieving timestamp from Result
Posted by Ted Yu <yu...@gmail.com>.
Since there may be more than one qualifier for a column family, is it
reasonable to add Result.getColumnLatest(byte[]) which returns the latest
column for given family ?
Thanks
On Mon, Nov 15, 2010 at 2:12 PM, Ryan Rawson <ry...@gmail.com> wrote:
> The javadoc details what to expect.
>
> You can also call Result.getColumnLatest(byte[],byte[])
>
> The resulting KeyValue has methods like getTimestamp() etc.
>
> -ryan
>
>
> On Mon, Nov 15, 2010 at 2:02 PM, Ted Yu <yu...@gmail.com> wrote:
> > We used the following code to see if the "Cell" (pardon me for using the
> old
> > term) returned from scanner was of certain timestamp:
> > if (result.getCellValue().getTimestamp() == ts){
> >
> > In 0.90, I don't see method which returns the timestamp for Result.
> > I am wondering if the above check can be omitted since we specify the
> > following for the Scan:
> > scan.setTimeStamp(ts);
> > If not, please advise the correct way of retrieving timestamp from
> Result.
> >
> > If I call Result.raw() and get two KeyValue's, which should be the
> KeyValue
> > whose timestamp conforms to the semantics of our check shown at the top ?
> >
> > Thanks
> >
> > On Mon, Nov 15, 2010 at 12:38 PM, Ryan Rawson <ry...@gmail.com>
> wrote:
> >
> >> That is correct, those classes were deprecated in 0.20, and now gone in
> >> 0.90.
> >>
> >> Now you will want to use HTable and Result.
> >>
> >> Also Filter.getNextKeyHint() is an implementation detail, have a look
> >> at the other filters to get a sense of what it does.
> >>
> >> On Mon, Nov 15, 2010 at 12:33 PM, Ted Yu <yu...@gmail.com> wrote:
> >> > Just a few findings when I tried to compile our 0.20.6 based code with
> >> this
> >> > new release:
> >> >
> >> > HConstants is final class now instead of interface
> >> > RowFilterInterface is gone
> >> > org.apache.hadoop.hbase.io.Cell is gone
> >> > org.apache.hadoop.hbase.io.RowResult is gone
> >> > constructor
> >> >
> >>
> HColumnDescriptor(byte[],int,java.lang.String,boolean,boolean,int,boolean)
> >> > is gone
> >> > Put.setTimeStamp() is gone
> >> > org.apache.hadoop.hbase.filter.Filter has added
> >> > getNextKeyHint(org.apache.hadoop.hbase.KeyValue)
> >> >
> >> > If you know the alternative to some of the old classes, please share.
> >> >
> >> > On Mon, Nov 15, 2010 at 2:51 AM, Stack <st...@duboce.net> wrote:
> >> >
> >> >> The first hbase 0.90.0 release candidate is available for download:
> >> >>
> >> >> http://people.apache.org/~stack/hbase-0.90.0-candidate-0/<http://people.apache.org/%7Estack/hbase-0.90.0-candidate-0/>
> <http://people.apache.org/%7Estack/hbase-0.90.0-candidate-0/>
> >> <http://people.apache.org/%7Estack/hbase-0.90.0-candidate-0/>
> >> >>
> >> >> HBase 0.90.0 is the major HBase release that follows 0.20.0 and the
> >> >> fruit of the 0.89.x development release series we've been running of
> >> >> late.
> >> >>
> >> >> More than 920 issues have been closed since 0.20.0. Release notes
> are
> >> >> available here: http://su.pr/8LbgvK.
> >> >>
> >> >> HBase 0.90.0 runs on Hadoop 0.20.x. It does not currently run on
> >> >> Hadoop 0.21.0. HBase will lose data unless it is running on an
> >> >> Hadoop HDFS 0.20.x that has a durable sync. Currently only the
> >> >> branch-0.20-append branch [1] has this attribute. No official
> releases
> >> >> have been made from this branch as yet so you will have to build your
> >> >> own Hadoop from the tip of this branch or install Cloudera's CDH3 [2]
> >> >> (Its currently in beta). CDH3b2 or CDHb3 have the 0.20-append
> patches
> >> >> needed to add a durable sync. See CHANGES.txt [3] in
> >> >> branch-0.20-append to see list of patches involved.
> >> >>
> >> >> There is no migration necessary. Your data written with HBase 0.20.x
> >> >> (or with HBase 0.89.x) is readable by HBase 0.90.0. A shutdown and
> >> >> restart after putting in place the new HBase should be all thats
> >> >> involved. That said, once done, there is no going back to 0.20.x
> once
> >> >> the transition has been made. HBase 0.90.0 and HBase 0.89.x write
> >> >> region names differently in the filesystem. Rolling restart from
> >> >> 0.20.x or 0.89.x to 0.90.0RC0 will not work.
> >> >>
> >> >> Should we release this candidate as hbase 0.90.0? Take it for a
> spin.
> >> >> Check out the doc. Vote +1/-1 by November 22nd.
> >> >>
> >> >> Yours,
> >> >> The HBasistas
> >> >> P.S. For why the version 0.90 and whats new in HBase 0.90, see slides
> >> >> 4-10 in this deck [4]
> >> >>
> >> >> 1.
> >> http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-append
> >> >> 2. http://archive.cloudera.com/docs/
> >> >> 3.
> >> >>
> >>
> http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-append/CHANGES.txt
> >> >> 4. http://hbaseblog.com/2010/07/04/hug11-hbase-0-90-preview-wrap-up/
> >> >>
> >> >
> >>
> >
>
Re: retrieving timestamp from Result
Posted by Ryan Rawson <ry...@gmail.com>.
The javadoc details what to expect.
You can also call Result.getColumnLatest(byte[],byte[])
The resulting KeyValue has methods like getTimestamp() etc.
-ryan
On Mon, Nov 15, 2010 at 2:02 PM, Ted Yu <yu...@gmail.com> wrote:
> We used the following code to see if the "Cell" (pardon me for using the old
> term) returned from scanner was of certain timestamp:
> if (result.getCellValue().getTimestamp() == ts){
>
> In 0.90, I don't see method which returns the timestamp for Result.
> I am wondering if the above check can be omitted since we specify the
> following for the Scan:
> scan.setTimeStamp(ts);
> If not, please advise the correct way of retrieving timestamp from Result.
>
> If I call Result.raw() and get two KeyValue's, which should be the KeyValue
> whose timestamp conforms to the semantics of our check shown at the top ?
>
> Thanks
>
> On Mon, Nov 15, 2010 at 12:38 PM, Ryan Rawson <ry...@gmail.com> wrote:
>
>> That is correct, those classes were deprecated in 0.20, and now gone in
>> 0.90.
>>
>> Now you will want to use HTable and Result.
>>
>> Also Filter.getNextKeyHint() is an implementation detail, have a look
>> at the other filters to get a sense of what it does.
>>
>> On Mon, Nov 15, 2010 at 12:33 PM, Ted Yu <yu...@gmail.com> wrote:
>> > Just a few findings when I tried to compile our 0.20.6 based code with
>> this
>> > new release:
>> >
>> > HConstants is final class now instead of interface
>> > RowFilterInterface is gone
>> > org.apache.hadoop.hbase.io.Cell is gone
>> > org.apache.hadoop.hbase.io.RowResult is gone
>> > constructor
>> >
>> HColumnDescriptor(byte[],int,java.lang.String,boolean,boolean,int,boolean)
>> > is gone
>> > Put.setTimeStamp() is gone
>> > org.apache.hadoop.hbase.filter.Filter has added
>> > getNextKeyHint(org.apache.hadoop.hbase.KeyValue)
>> >
>> > If you know the alternative to some of the old classes, please share.
>> >
>> > On Mon, Nov 15, 2010 at 2:51 AM, Stack <st...@duboce.net> wrote:
>> >
>> >> The first hbase 0.90.0 release candidate is available for download:
>> >>
>> >> http://people.apache.org/~stack/hbase-0.90.0-candidate-0/<http://people.apache.org/%7Estack/hbase-0.90.0-candidate-0/>
>> <http://people.apache.org/%7Estack/hbase-0.90.0-candidate-0/>
>> >>
>> >> HBase 0.90.0 is the major HBase release that follows 0.20.0 and the
>> >> fruit of the 0.89.x development release series we've been running of
>> >> late.
>> >>
>> >> More than 920 issues have been closed since 0.20.0. Release notes are
>> >> available here: http://su.pr/8LbgvK.
>> >>
>> >> HBase 0.90.0 runs on Hadoop 0.20.x. It does not currently run on
>> >> Hadoop 0.21.0. HBase will lose data unless it is running on an
>> >> Hadoop HDFS 0.20.x that has a durable sync. Currently only the
>> >> branch-0.20-append branch [1] has this attribute. No official releases
>> >> have been made from this branch as yet so you will have to build your
>> >> own Hadoop from the tip of this branch or install Cloudera's CDH3 [2]
>> >> (Its currently in beta). CDH3b2 or CDHb3 have the 0.20-append patches
>> >> needed to add a durable sync. See CHANGES.txt [3] in
>> >> branch-0.20-append to see list of patches involved.
>> >>
>> >> There is no migration necessary. Your data written with HBase 0.20.x
>> >> (or with HBase 0.89.x) is readable by HBase 0.90.0. A shutdown and
>> >> restart after putting in place the new HBase should be all thats
>> >> involved. That said, once done, there is no going back to 0.20.x once
>> >> the transition has been made. HBase 0.90.0 and HBase 0.89.x write
>> >> region names differently in the filesystem. Rolling restart from
>> >> 0.20.x or 0.89.x to 0.90.0RC0 will not work.
>> >>
>> >> Should we release this candidate as hbase 0.90.0? Take it for a spin.
>> >> Check out the doc. Vote +1/-1 by November 22nd.
>> >>
>> >> Yours,
>> >> The HBasistas
>> >> P.S. For why the version 0.90 and whats new in HBase 0.90, see slides
>> >> 4-10 in this deck [4]
>> >>
>> >> 1.
>> http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-append
>> >> 2. http://archive.cloudera.com/docs/
>> >> 3.
>> >>
>> http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-append/CHANGES.txt
>> >> 4. http://hbaseblog.com/2010/07/04/hug11-hbase-0-90-preview-wrap-up/
>> >>
>> >
>>
>