How do we get Index fields of an Object in Apex?

Question

I want all the index fields of a particular object in apex. I have searched through the Schema describe but couldn't find a way to identify the field as indexed.

Answer 1

It's not in the describe, but you can query the FieldDefinition via the Tooling API and it has an IsIndexed field.

List<FieldDefinition> indexedAccountFields = [
    SELECT QualifiedApiName FROM FieldDefinition WHERE IsIndexed = true
    AND EntityDefinition.QualifiedApiName = 'Account'
];