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From Dinusha Dilrukshi <sdddilruk...@gmail.com>
Subject Re: Issues with writing data to Cassandra column family using a Hive script
Date Mon, 11 Feb 2013 03:56:20 GMT
Hi Aaron,

Thanks for the reply.. I ll try out your suggestion.

Regards,
Dinusha.

On Mon, Feb 11, 2013 at 1:55 AM, aaron morton <aaron@thelastpickle.com>wrote:

> Don't use the variable length Cassandra integer, use the Int32Type. It
> also sounds like you want to use a DoubleType rather than FloatType.
>
> http://www.datastax.com/docs/datastax_enterprise2.2/solutions/about_hive#hive-to-cassandra-table-mapping
>
> Cheers
>
>
> -----------------
> Aaron Morton
> Freelance Cassandra Developer
> New Zealand
>
> @aaronmorton
> http://www.thelastpickle.com
>
> On 10/02/2013, at 4:15 PM, Dinusha Dilrukshi <sdddilrukshi@gmail.com>
> wrote:
>
> Hi All,
>
> Data was originally stored in column family called "test_cf". Definition
> of column family is as follows:
>
> CREATE COLUMN FAMILY test_cf
> WITH COMPARATOR = 'IntegerType'
>  AND key_validation_class = UTF8Type
>  AND default_validation_class = FloatType;
>
> And, following is the sample data set that contains in "test_cf".
>
> cqlsh:temp_ks> select * from test_cf;
>  key            | column1    | value
> ------------------+----------------+-------
>  localhost:8282 | 1350468600 |    76
>  localhost:8282 | 1350468601 |    76
>
>
> Hive script (shown in the end of mail) is use to take the data from above
> column family "test_cf" and insert into a new column family
> called "cpu_avg_5min_new7". Column family description
> of "cpu_avg_5min_new7" is also same as the test_cf. Issue is, data written
> in to "cpu_avg_5min_new7" column family after executing the hive script is
> as follows. It's not in the format  of data present in the original column
> family "test_cf". Any explanations would highly appreciate..
>
>
> cqlsh:temp_ks> select * from cpu_avg_5min_new7;
>  key            | column1                  | value
> ------------------+------------------------------+----------
>  localhost:8282 | 232340574229062170849328 | 1.09e-05
>  localhost:8282 | 232340574229062170849329 | 1.09e-05
>
>
> Hive script:
> ----------------
> drop table cpu_avg_5min_new7_hive;
> CREATE EXTERNAL TABLE IF NOT EXISTS cpu_avg_5min_new7_hive (src_id STRING,
> start_time INT, cpu_avg FLOAT) STORED BY
> 'org.apache.hadoop.hive.cassandra.CassandraStorageHandler' WITH
> SERDEPROPERTIES (
>  "cassandra.host" = "127.0.0.1" , "cassandra.port" = "9160" , "
> cassandra.ks.name" = "temp_ks" ,
>  "cassandra.ks.username" = "xxx" , "cassandra.ks.password" = "xxx" ,
>  "cassandra.columns.mapping" = ":key,:column,:value" , "cassandra.cf.name"
> = "cpu_avg_5min_new7" );
>
> drop table xxx;
> CREATE EXTERNAL TABLE IF NOT EXISTS xxx (src_id STRING, start_time INT,
> cpu_avg FLOAT) STORED BY
>  'org.apache.hadoop.hive.cassandra.CassandraStorageHandler' WITH
> SERDEPROPERTIES (
>  "cassandra.host" = "127.0.0.1" , "cassandra.port" = "9160" , "
> cassandra.ks.name" = "temp_ks" ,
>   "cassandra.ks.username" = "xxx" , "cassandra.ks.password" = "xxx" ,
>    "cassandra.columns.mapping" = ":key,:column,:value" , "
> cassandra.cf.name" = "test_cf" );
>
> insert overwrite table cpu_avg_5min_new7_hive select
> src_id,start_time,cpu_avg from xxx;
>
> Regards,
> Dinusha.
>
>
>
>

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