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HBase >> mail # user >> Why only check1-and-putMany and check1-and-deleteMany?


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-
Re: Why only check1-and-putMany and check1-and-deleteMany?
Looking at hbase-server/src/main/protobuf/Client.proto in trunk, I tried
the following formation to see if we can pass more than one qualifier:

Index: hbase-server/src/main/protobuf/Client.proto
==================================================================--- hbase-server/src/main/protobuf/Client.proto    (revision 1411337)
+++ hbase-server/src/main/protobuf/Client.proto    (working copy)
@@ -97,7 +97,7 @@
 message Condition {
   required bytes row = 1;
   required bytes family = 2;
-  required bytes qualifier = 3;
+  repeated bytes qualifier = 3;
   required CompareType compareType = 4;
   required Comparator comparator = 5;
 }

protoc is able to compile the above code.
This means we can potentially compare more than one qualifier in the check
step.

More discussion is needed to figure out the proper API which would be a
superset of what we have today:
  public boolean checkAndPut(final byte [] row,
      final byte [] family, final byte [] qualifier, final byte [] value,
      final Put put)

Cheers

On Sat, Nov 17, 2012 at 10:28 PM, Mike Spreitzer <[EMAIL PROTECTED]>wrote:

> I am not looking at the trunk.  I am just a user looking at the interface
> documented on the web site and wondering why the atomic composite
> functionality is so limited.  It is not hard to imagine an expanded
> interface that allows checking an arbitrary set of columns and, if each
> has a value specified for it, doing an arbitrary set of Mutations.
>
> Thanks,
> Mike
>
>
>
> From:   Ted Yu <[EMAIL PROTECTED]>
> To:     [EMAIL PROTECTED]
> Date:   11/17/2012 11:44 PM
> Subject:        Re: Why only check1-and-putMany and check1-and-deleteMany?
>
>
>
> Are you looking at trunk code ?
>
> In trunk, take a look at HRegion.checkAndMutate() where you can specify
> ByteArrayComparable which does the comparison (matching).
> There is still the limit of single value:
>         } else if (result.size() == 1 && !valueIsNull) {
>           KeyValue kv = result.get(0);
>
> For the moment, only Put and Delete are supported:
>
>     if (!isPut && !(w instanceof Delete))
>       throw new DoNotRetryIOException("Action must be Put or Delete");
> If you have suggestion on how the check part can be more general, please
> comment.
>
> Thanks
>
> On Sat, Nov 17, 2012 at 7:30 PM, Mike Spreitzer <[EMAIL PROTECTED]>
> wrote:
>
> > If I understand correctly, an HTable has two composite atomic
> operations,
> > checkAndPut and checkAndDelete.  The check part checks just a single
> > column's value.  Why not allow checking more than one column?
> >
> > Why no checkAndAppend?
> >
> > The checkAndPut operation can put to multiple columns, right?  And the
> > checkAndDelete operation can delete multiple columns, right?  Why not
> let
> > them be mixed?  Why not checkAndMutate?
> >
> > Thanks!
> > Mike
>
>