Difference

Description

This operation finds the difference between the primary (first) set and all other specified sets. To find the difference, the operation subtracts identical values across multiple sets and returning the remainder (i.e. the difference) in a new set. The first set in the request is considered the main set whose remainder is left after the subtraction operation.

Method

Backendless.Hive(hiveName).SetStore().difference(keyNames);

where:

Argument	Description
hiveName	Name of a hive where the operation is performed. String value.
keyNames	A set containing key names each identifying a set. Must be a set of string values.

Return Value

An array containing values retrieved after the primary and all other consecutive sets are subtracted. Each individual value is of the any data type.

Example

The example below subtracts all identical values and returns a new set containing the remainder.

Set<String> keyNames = new HashSet<>();
keyNames.add( "cars" );
keyNames.add( "cars_2" );

Backendless.Hive("transport").SetStore().difference(keyNames);

where:

Argument	Description
"transport"	Name of a hive where the operation is performed.
keyNames	A set of key names each identifying a set containing multiple values.

Contents Of Specified Sets

Response

Codeless Reference

where:

Argument	Description
hive name	Name of a hive where the operation is performed.
key names	A list containing key names identifying unique sets.

Returns a list containing values retrieved after the primary and all other consecutive sets are subtracted.

Consider the following Set storages:

The example below subtracts items in the following sets: "cars" and "cars_2"; and gets the remainder:


The output will look as shown below after the Codeless logic runs. Unique items(i.e. "Coupe") that are outside of the primary set("cars") are skipped.