FirebaseFirestore Framework Reference

RandomExpression

public class RandomExpression : FunctionExpression, @unchecked Sendable

A RandomExpression is a FunctionExpression that generates a random floating-point number between 0.0 (inclusive) and 1.0 (exclusive).

This expression is useful when you need to introduce a random value into a pipeline, for example, to randomly sample a subset of documents.

Example of using RandomExpression to sample documents:

// Create a query to sample approximately 10% of the documents in a collection
firestore.pipeline()
  .collection("users")
  .where(rand().lessThan(0.1))

• init()

  Creates a new RandomExpression that generates a random number.

  Declaration

  Swift

  public init()