如何使用Firestore - Swift合并两个查询

import Firebase

// 创建两个查询
let query1 = Firestore.firestore().collection("collection1").whereField("field1", isEqualTo: "value1")
let query2 = Firestore.firestore().collection("collection2").whereField("field2", isEqualTo: "value2")

// 执行查询并获取结果
query1.getDocuments { (snapshot, error) in
    if let error = error {
        print("Error querying collection1: \(error)")
    } else {
        var results1 = [DocumentSnapshot]()
        for document in snapshot!.documents {
            results1.append(document)
        }
        
        // 合并结果
        query2.getDocuments { (snapshot, error) in
            if let error = error {
                print("Error querying collection2: \(error)")
            } else {
                var results2 = [DocumentSnapshot]()
                for document in snapshot!.documents {
                    results2.append(document)
                }
                
                let mergedResults = results1 + results2
                
                // 使用合并后的结果进行后续操作
                // ...
            }
        }
    }
}