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Why do we use map in Apex?
A map is a collection of key-value pairs where each unique key maps to a single value. Keys and values can be any data type—primitive types, collections, sObjects, user-defined types, and built-in Apex types. Map keys and values can contain any collection, and can contain nested collections.
What is the difference between list and set in Apex?
A list is an ordered collection of elements that are distinguished by their indices. List elements can be of any data type—primitive types, collections, sObjects, user-defined types, and built-in Apex types. A set is an unordered collection of elements that do not contain any duplicates.
Why use a set over a List?
Set doesn’t allow null value and duplicate value The user of this interface has precise control over where in the list each element is inserted. The user can access elements by their integer index (position in the list), and search for elements in the list. Unlike sets, lists typically allow duplicate elements.
When to use a map or a list in apex?
A list is an ordered collection so use list when you want to identify list element based on Index Number. A map is a collection of key-value pairs where each unique key maps to a single value. Keys can be any primitive data type, while values can be a primitive, sObject, collection type or an Apex object.
When to use a map or a list?
This question was answered on the official Salesforce Developer forums here. A list is an ordered collection so use list when you want to identify list element based on Index Number. A map is a collection of key-value pairs where each unique key maps to a single value.
What are the different types of collections in apex?
Unlike Java, which only has one type of collection (Arrays, also know as a Lists), Apex has three to choose from: Lists, Sets, and Maps. Together, we’ll go into each of these types of collections and show you what they are best used for, and how to use them when you start coding.
When to use a list in apex trigger?
Whether you’re using an Apex Trigger or just a process within an Apex class their usage is the same regardless. This question was answered on the official Salesforce Developer forums here. A list is an ordered collection so use list when you want to identify list element based on Index Number.