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A Script for Dumping Data From Cassandra

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A Script for Dumping Data From Cassandra

· Database Zone ·
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Built by the engineers behind Netezza and the technology behind Amazon Redshift, AnzoGraph is a native, Massively Parallel Processing (MPP) distributed Graph OLAP (GOLAP) database that executes queries more than 100x faster than other vendors.  

To manage our database migrations for Cassandra, we've taken to creating scripts that create/modify the schema and populate configuration data. In my previous post, I showed how to dump and load the schema (keyspaces and column families).

Here is a code snippet that lets you dump the data into set statements that you can then load via the CLI.

     public void dumpColumnFamily() {  
         String columnFamily = "YOUR_COLUMN_FAMILY";  
         Cluster cluster = HFactory.getOrCreateCluster("dev", "localhost:9160");  
         Keyspace keyspace = HFactory.createKeyspace("YOUR_KEYSPACE", cluster);  
         RangeSlicesQuery<String, String, String> rangeSlicesQuery = HFactory  
                 .createRangeSlicesQuery(keyspace, StringSerializer.get(),  
                         StringSerializer.get(), StringSerializer.get());  
         rangeSlicesQuery.setColumnFamily(columnFamily);  
         rangeSlicesQuery.setKeys("", "");  
         rangeSlicesQuery.setRange("", "", false, 2000); // MAX_COLUMNS  
         rangeSlicesQuery.setRowCount(2000); // MAX_ROWS  
         QueryResult<OrderedRows<String, String, String>> result = rangeSlicesQuery .execute();  
         OrderedRows<String, String, String> orderedRows = result.get();  
         for (Row<String, String, String> r : orderedRows) {  
             ColumnSlice<String, String> slice = r.getColumnSlice();  
             for (HColumn<String, String> column : slice.getColumns()) {  
                 System.out.println("set " + columnFamily + "['" + r.getKey()  
                         + "']" + "['" + column.getName() + "'] = '"  
                         + column.getValue() + "';");  
             }  
         }  
     }  

 

Download AnzoGraph now and find out for yourself why it is acknowledged as the most complete all-in-one data warehouse for BI style and graph analytics.  

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