How to efficiently use Batch writes to cassandra using datastax java driver? -

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I need to write in the bass in the cassandra using the datestacks java driver and this is my first time, i databstack I'm trying to use Java driver, so I'm having some confusion -

Below is my code in which I am trying to create a statement object and add it to the batch, as well as the form of a quorum Establish compatibility level in I do. 

  session session = null; Cluster cluster = null; // Here we build Cluster and Session object and we also use DowngradingConsistencyRetryPolicy // cluster = builder.withSocketOptions (socketOpts) .withRetryPolicy (DowngradingConsistencyRetryPolicy.INSTANCE) Public Zero insertMetadata (List & quot; ListAdress & lt; List & quot; listAddress) {/ What is the purpose of unlog batch here? Batch batch = QueryBuilder.unloggedBatch (); . {Try, {insert statement} = insertInto ("test_table") value (New String [] {"address", "name" "LAST_MODIFIED_DATE", "client_id"}, new object [] {data for {AddressMetadata data: listAddress} .getAddress (), data. GetName (), data. GetLastModifiedDate (), 1}); // is this the correct way to set the level of stability for batch? insert.setConsistencyLevel (ConsistencyLevel.QUORUM); batch.add (insert); } // Now execute batch session.execute (batch); } Hold (NoHostAvailableException E) {// log an exception} hold (QueryExecutionException E) {// an exception} hold (QueryValidationException e) log {// log an exception} hold (IllegalStateException e) {/ / Log an exception} hold (exception e) {// one exception log in}}   
 and below my  address matadata  class -  
  public class address matadata {the name of the private string; Private string address; Private date end date date; Public string getName () {return name; } Public Zero Setname (string name) {this.name = name; } Public string getAddress () {return address; } Public Zero Setdude (String Address) {this.address = address; } Public Date getLastModifiedDate () {last Last Updated Date; } Public Zero Siteloadeddidified date (dated last date) {this.last.ModifiedDate = lastModifiedDate; }}   
 Now I have a question - am I using batch to include in the cassandra with datestacks java driver, is it correct? Regarding the retrieval policies, which means that the execution of the batch statement has failed, what will happen, will it try again again?  
 And is there a better way for the casandra to write a batch using a Java driver?   
 
 
 A small tiger first:  
 Batch keyword in Cassandra  No  A display optimization for batching with large buckets of data for heavy loads.  
 Bats are used to group together atomic operations, which you expect to be together. Batch guarantees that if one part of your batch is successful, then the whole batch is successful.  
  Use of batches probably will not run on your large scale   
 For your questions now:  
 
 unloggedBatch What is the purpose here?   
 Cassandra uses a mechanism to ensure the atomicity of a batch so that the batch is used to enter. By specifying unauthorized batch, you are closing this functionality so that the batch is no longer nuclear and partially failed to complete. Naturally, there is a performance penalties for entering your batches and ensuring their atom, which will remove this penalty using unused batches.  
 There are some cases in which you can request that the request) which are related to the same partition are sent together. If you operate batch simultaneously and they need to be performed in separate divisions / nodes, then you are essentially working more for your coordinator. See the specific example of this in Ryan's blog:  
  
 
 Now my question is - am I using batch to put in the cassandra with the Dystestax Java driver ? / P>  
 I do not see anything wrong in your code, just depends on what you are trying to achieve.  
 
 And again about the retrieval policies, which means that if the execution of the batch statement fails, what will happen again, will it try again again?   
 This is a batch of its own, if it fails, it will not retry itself. The driver has policies again but you have to apply them separately.  
 The default policy in the Java driver only retries in these scenarios:  
     
  •  At a reading time, if sufficient replication was answered but the data was not retrieved .  
  •  Once the typing time ends, we will end the time while writing the distributed logs used by the batch statement.   
     Read more about this and consider it on the basis of your usage.  p>

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