Processing resources at a storage system for a database server are utilized to perform aspects of a join operation that would conventionally be performed by the database server. When requesting a range of data units from a storage system, the database server includes join metadata describing aspects of the join operation for which the data is being requested. The join metadata may be, for instance, a bloom filter. The storage system reads the requested data from disk as normal. However, prior to sending the requested data back to the storage system, the storage system analyzes the raw data based on the join metadata, removing a certain amount of data that is guaranteed to be irrelevant to the join operation. The storage system then returns filtered data to the database server. The database system thereby avoids the unnecessary transfer of certain data between the storage system and the database server.