What is the difference between a list a set and a Map?

Duplicates Another notable difference between List , Set and Map interface is that a List can have duplicate elements, a set contains only distinct elements, and a Map doesn’t permit duplicate keys, i.e., each key can map to at most one value.

Why do we use Map in Salesforce?

On Salesforce, the term “map” refers to a set of key value pairs, meaning that it can govern data ranging from primitive data, Apex objects, sObjects, among others.

What are lists and maps?

A Map is an object that maps keys to values or is a collection of attribute-value pairs. The list is an ordered collection of objects and the List can contain duplicate values. The Map has two values (a key and value), while a List only has one value (an element).

How do I use a Map in Salesforce?

To declare a map, use the Map keyword followed by the data types of the key and the value within <> characters. For example: Map country_currencies = new Map(); Map> m = new Map>(); You can use the generic or specific sObject data types with maps.

What is the difference between List Set and Map in Salesforce?

A set is an unordered collection of elements that do not contain any duplicates. Set elements can be of any data type—primitive types, collections, sObjects, user-defined types, and built-in Apex types. A map is a collection of key-value pairs where each unique key maps to a single value.

What is difference between List and Set?

List and Set interfaces are one of them that are used to group the object. The main difference between List and Set is that Set is unordered and contains different elements, whereas the list is ordered and can contain the same elements in it.