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From José Elias Queiroga da Costa Araújo <je...@cesar.org.br>
Subject Re: Problems in the cassandra bulk loader
Date Thu, 10 Oct 2013 13:33:29 GMT
        Hi, I thought the bulk API could handle this, merging all columns
for the same super column. I did something like this in the java client
(Hector) where it is able to solve this conflict only appending the columns.

        Regarding to the column value, if the code is overwriting the
columns I expected the column had the last value of my collection, but it
is considering the first one.

        Regards,

        Elias.


2013/10/10 Viktor Jevdokimov <Viktor.Jevdokimov@adform.com>

> You overwrite your columns by writing new row/supercolumn.
>
> Remove new row/supercolumn from "for" statement, which is for columns:
>
>
> int rowKey = 10;
> int superColumnKey = 20;
> usersWriter.newRow(ByteBufferUtil.bytes(rowKey));
> usersWriter.newSuperColumn(ByteBufferUtil.bytes(superColumnKey));
> for (int i = 0; i < 10; i++) {
>         usersWriter.addColumn(
>                 ByteBufferUtil.bytes(i+1),
>                 ByteBufferUtil.bytes(i+1),
>                 System.currentTimeMillis());
>  }
>  usersWriter.close();
>
> Next time ask such questions in user mail list, not C* devs, which is for
> C* development, not usage/your code development around Cassandra.
>
>
>
>
>
> Best regards / Pagarbiai
>
> Viktor Jevdokimov
> Senior Developer
>
> Email: Viktor.Jevdokimov@adform.com
> Phone: +370 5 212 3063
> Fax: +370 5 261 0453
>
> J. Jasinskio 16C,
> LT-03163 Vilnius,
> Lithuania
>
>
>
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> irrevocably delete this message and any copies.-----Original Message-----
> From: José Elias Queiroga da Costa Araújo [mailto:jeqca@cesar.org.br]
> Sent: Wednesday, October 9, 2013 11:22 PM
> To: dev
> Subject: Problems in the cassandra bulk loader
>
>         Hi all,
>
>         I'm trying to use the bulk insertion with the
> SSTableSimpleUnsortedWriter class from cassandra API and I facing some
> problems.  After generating and uploading the .db files by using the
> ./sstableloader command , I noticed the data didn't match with inserted one.
>
>         I put the used code below to try to explain the bahaviour.
>
>          I'm trying to generate the data files using only one rowkey and
> one supercolumn. Where the super column has 10 columns.
>
> IPartitioner p = new Murmur3Partitioner(); CFMetaData scf = new
> CFMetaData("myKeySpace", "Column",  ColumnFamilyType.Super,
> BytesType.instance, BytesType.instance);
>
> SSTableSimpleUnsortedWriter usersWriter = new
> SSTableSimpleUnsortedWriter(new File("./"), scf, p,64);
>
> int rowKey = 10;
> int superColumnKey = 20;
> for (int i = 0; i < 10; i++) {
>  usersWriter.newRow(ByteBufferUtil.bytes(rowKey));
> usersWriter.newSuperColumn(ByteBufferUtil.bytes(superColumnKey));
>  usersWriter.addColumn(ByteBufferUtil.bytes(i+1),ByteBufferUtil.bytes(i+1),
> System.currentTimeMillis());
>  }
>  usersWriter.close();
>
>                 After uploading,  the result is:
>
>                 RowKey: 0000000a
>                    => (super_column=00000014,
>                               (name=00000001, value=00000001,
> timestamp=1381348293144))
>
>                 1 Row Returned.
>
>                 In this case, my super column should have 10 columns? With
> values between 00000001 to 00000011?  Since I'm using the same super
> column.  The documentation says the newRow method could be invoked many
> times, it impacts only the performance.
>
>                 The second question is: If this is the correct behavior,
> the column value should be 00000011, since it is the last value passed as
> argument to addColumn(...) method in the loop?
>
>               Thanks in the advance,
>
>                Elias.
>

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