The Global Data Plane (GDP) is a data-centric network infrastructure that provides federated access to compute resources. However, an environment in which code runs on untrusted hardware introduces new security challenges for data management. Furthermore, DataCapsules, which are the high-level logical units of transfer that move through the GDP, can store persistent data but are difficult to search through efficiently, requiring users to understand their somewhat complex security structures for correct usage. CapsuleDB is the first database and key-value store designed for the GDP. It exports a simple interface for developers without jeopardizing any of the security guarantees inherent to DataCapsules. Furthermore, it uses a novel indexing system to track active data and naturally age out older data by leveraging the unique structure of DataCapsules. Finally, it uses Intel SGX to protect against malicious host operating systems, providing an extra layer of security for deployments to nodes owned by other entities.