Deleting Multiple Objects

This API deletes multiple objects in a data table with a single request. Consider the following example, it demonstrates an API call which deletes all objects in the Person data table where the value of the age property is greater than 20:

AsyncCallback<int> bulkDeleteCallback = new AsyncCallback<int>(
  objectsDeleted =>
  {
    System.Console.WriteLine( String.Format( "Server has deleted {0} objects in the database", objectsDeleted ) );
  },
  error =>
  {
    System.Console.WriteLine( "Server returned an error " + error.Message );
  } );

Backendless.Data.Of( "Person" ).Remove( "age > 20",bulkDeleteCallback );

Blocking Method

Using DictionaryCustom Class

int Backendless.Data.Of( "TABLE-NAME" ).Remove( String whereClause );

int Backendless.Data.Of<E>().Remove( String whereClause );

Non-Blocking API

Using DictionaryCustom Class

void Backendless.Data.Of( "TABLE-NAME" ).Remove( String whereClause, 
                                               AsyncCallback<int> responder )

void Backendless.Data.Of<E>().Remove( String whereClause, AsyncCallback<int> responder )

where:

Argument	Description
TABLE-NAME	Name of the table where the objects are deleted.
E	A .NET class of the data objects to delete.
whereClause	A condition for selecting objects to be deleted in the data table.
responder	a responder object which will receive a callback when the method successfully deleted the objects or if an error occurs. Applies to the non-blocking method only.

Return Value

The method returns the number of objects deleted in the database.

Codeless Reference

where:

Argument	Description
table name	Name of the data table where objects will be deleted from.
where clause	A condition for selecting objects to be deleted in the data table. Refer to the Search With The Where Clause topic for more information.

Returns the number of deleted objects.

Consider the following records in the employees data table:

The example below is set to delete all values from the position column that match the where clause condition, (e.g. 'Manager'). In this case, the condition acts like a filter and deletes all values that match the criteria 'Manager'.

The result of this operation will look as shown below after the Codeless logic runs. As you can see, two records containing the 'Manager' value in the position column were deleted from the data table.

Also, the operation has returned the number 2, indicating the number of deleted objects in the employees data table.