Creating indexes

To perform queries, you must create an index.

• Create an index that includes the data type. Indexing with the data type is useful when an object mapper is set on the data store.
  BEFORE (with IMFData/CloudantToolkit):

   // Use an existing data store
  CDTStore *store = existingStore;
  
  // The data type to use for the Automobile class
  NSString *dataType = [store.mapper dataTypeForClassName:NSStringFromClass([Automobile class])];
  
  // Create the index
  [store createIndexWithDataType:dataType fields:@[@"year", @"make"] completionHandler:^(NSError *error) {
      if(error){
          // Handle error
      }else{
          // Continue application flow
      }
  }];

  // A store that has been previously created.
  let store:CDTStore = existingStore
  
  // The data type to use for the Automobile class
  let dataType:String = store.mapper.dataTypeForClassName(NSStringFromClass(Automobile.classForCoder()))
  
  // Create the index
  store.createIndexWithDataType(dataType, fields: ["year","make"]) { (error:NSError!) -> Void in
      if nil != error {
          // Handle error
      } else {
          // Continue application flow
      }
  }

  

  // Use an existing data store
  Store store = existingStore;
  
  // The data type to use for the Automobile class
  String dataType = store.getMapper().getDataTypeForClassName(Automobile.class.getCanonicalName());
  
  // The fields to index.
  List<IndexField> indexFields = new ArrayList<IndexField>();
  indexFields.add(new IndexField("year"));
  indexFields.add(new IndexField("make"));
  
  // Create the index
  Task<Void> indexTask = store.createIndexWithDataType(dataType, indexFields);
  indexTask.continueWith(new Continuation<Void, Void>() {
      @Override
      public Void then(Task<Void> task) throws Exception {
          if(task.isFaulted()){
              // Handle error
          }else{
              // Continue application flow
          }
          return null;
      }
  });

  AFTER (with Cloudant Sync):

  // A store that has been previously created.
  CDTDatastore *datastore = existingDatastore;
  
  NSString *indexName = [datastore ensureIndexed:@[@"@datatype", @"year", @"make"] withName:@"automobileindex"];
  if(!indexName){
      // Handle error
  }

  // A store that has been previously created.
  let datastore:CDTDatastore = existingDatastore
  
  // Create the index
  let indexName:String? = datastore.ensureIndexed(["@datatype","year","make"], withName: "automobileindex")
  if(indexName == nil){
      // Handle error
  }

  

  // Use an existing store
  Datastore datastore = existingStore;
  
  // Create an IndexManager
  IndexManager indexManager = new IndexManager(datastore);
  
  // The fields to index.
  List<Object> indexFields = new ArrayList<Object>();
  indexFields.add("@datatype");
  indexFields.add("year");
  indexFields.add("make");
  
  // Create the index
  indexManager.ensureIndexed(indexFields, "automobile_index");

• Delete indexes.
  BEFORE (with IMFData/CloudantToolkit):

  // Use an existing data store
  CDTStore *store = existingStore;
  NSString *indexName = existingIndexName;
  
  // Delete the index
  [store deleteIndexWithName:indexName completionHandler:^(NSError *error) {
      if(error){
          // Handle error
      }else{
          // Continue application flow
      }
  }];

  // Use an existing store
  let store:CDTStore = existingStore
  
  // The data type to use for the Automobile class
  let dataType:String = store.mapper.dataTypeForClassName(NSStringFromClass(Automobile.classForCoder()))
  
  // Delete the index
  store.deleteIndexWithDataType(dataType, completionHandler: { (error:NSError!) -> Void in
      if nil != error {
          // Handle error
      } else {
          // Continue application flow
      }
  })

  

  // Use an existing data store
  Store store = existingStore;
  String indexName = existingIndexName;
  
  // Delete the index
  Task<Void> indexTask = store.deleteIndex(indexName);
  indexTask.continueWith(new Continuation<Void, Void>() {
      @Override
      public Void then(Task<Void> task) throws Exception {
          if(task.isFaulted()){
              // Handle error
          }else{
              // Continue application flow
          }
          return null;
      }
  });

  AFTER (with Cloudant Sync):

  // Use an existing store
  CDTDatastore *datastore = existingDatastore;
  NSString *indexName = existingIndexName;
  
  // Delete the index
  BOOL success = [datastore deleteIndexNamed:indexName];
  if(!success){
      // Handle error
  }

  // A store that has been previously created.
  let datastore:CDTDatastore = existingDatastore
  let indexName:String = existingIndexName
  
  // Delete the index
  let success:Bool = datastore.deleteIndexNamed(indexName)
  if(!success){
      // Handle error
  }

  

  // Use an existing store
  Datastore datastore = existingStore;
  String indexName = existingIndexName;
  IndexManager indexManager = existingIndexManager;
  
  // Delete the index
  indexManager.deleteIndexNamed(indexName);