Edge computing pushes application logic and the underlying data to the edge of the network, with the aim of improving availability and scalability. As the edge servers are not necessarily secure, there must be provisions for users to validate the results—that values in the result tuples are not tampered with, that no qualifying data are left out, that no spurious tuples are introduced, and that a query result is not actually the output from a different query. This paper aims to address the challenges of ensuring data integrity in edge computing. We study three schemes that enable users to check the correctness of query results produced by the edge servers. Two of the schemes are our original contributions, while the third is an adaptation of existing work. Our study shows that each scheme offers different security features, and imposes different demands on the edge servers, user machines, and interconnecting network. In other words, all three schemes are useful for different application requirements and resource configurations.