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From Abhijit Chanda <abhijit.chan...@gmail.com>
Subject Re: Retrieve data from Cassandra database using Datastax java driver
Date Sun, 21 Apr 2013 05:09:03 GMT
You have the collection attributeNames, just iterate it
      Iterator<Row> it = result.iterator();
        while(it.hasNext()){
            Row row = it.next();
            for(String column : attributeNames) {
                //not sure how to put the columnName and columnValue that
came back from the database
                attributes.put(column,row.getString(column));
            }
        }


Cheers


On Sun, Apr 21, 2013 at 10:24 AM, Techy Teck <comptechgeeky@gmail.com>wrote:

> Thanks Dave for the suggestion. I have all my columns name in this
> collection-
>
>                  *final Collection<String> attributeNames*
> *
> *
> And all my results back in this resultset-
>
>                 *ResultSet result =
> CassandraDatastaxConnection.getSession().execute(query);*
> *
> *
> Now I need to store the column name and its corresponding value in the
> Below Map-
>
>               *Map<String, String> attributes = new
> ConcurrentHashMap<String, String>();*
> *
> *
> What's the best way to do that in this case?
>
> Thanks for the help.
>
>
>
>
>
>
> On Sat, Apr 20, 2013 at 9:36 PM, Dave Brosius <dbrosius@mebigfatguy.com>wrote:
>
>>  getColumnDefinitions only returns meta data, to get the data, use the
>> iterator to navigate the rows
>>
>>
>> Iterator<Row> it = result.iterator();
>>
>> while (it.hasNext()) {
>>     Row r = it.next();
>>     //do stuff with row
>>
>> }
>>
>> On 04/21/2013 12:02 AM, Techy Teck wrote:
>>
>>  I am working with Datastax java-driver. And I am trying to retrieve few
>> columns from the database basis on the input that is being passed to the
>> below method-
>>
>>
>>  public Map<String, String> getAttributes(final String userId, final
>> Collection<String> attributeNames) {
>>
>>  String query="SELECT " +attributeNames.toString().substring(1,
>> attributeNames.toString().length()-1)+ " from profile where id = '"+userId+
>> "';";
>>   CassandraDatastaxConnection.getInstance();
>>
>>  ResultSet result =
>> CassandraDatastaxConnection.getSession().execute(query);
>>
>>  Map<String, String> attributes = new ConcurrentHashMap<String,
>> String>();
>>   for(Definition def : result.getColumnDefinitions()) {
>>  //not sure how to put the columnName and columnValue that came back from
>> the database
>>  attributes.put(column name, column value);
>>  }
>>   return attributes;
>>  }
>>
>>  Now I got the result back from the database in *result*
>> *
>> *
>> Now how to put the colum name and column value that came back from the
>> database in a map?
>>
>>  I am not able to understand how to retrieve colum value for a
>> particular column in datastax java driver?
>>
>>  Any thoughts will be of great help.
>>
>>
>>
>


-- 
-Abhijit

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