Data integrity in cloud databases is a topic that has received a much of attention from the research community. However, existing solutions mainly focus on the cloud providers that store data in relational databases, whereas nowadays many cloud providers store data in non-relational databases as well. In this paper, we focus on the particular family of non-relational databases—column-oriented stores, and present a protocol that will allow cloud users to verify the integrity of their data that resides on cloud databases of this type. We like our solution to be easily integrated with the existing real-world systems and therefore assume that we cannot modify the cloud; our protocol is implemented solely on the client side. We have implemented a prototype of our solution, that uses Cloud BigTable as a cloud database, and have evaluated its performance and correctness.