Embodiments are directed to mapping encryption policies to user data stored in a database using a policy column uniform resource identifier (URI). In one scenario, a computer system receives the following: a database schema name that identifies the name of a specified schema within a relational database in which user data is stored, a table name that identifies a specified table within the relational database, a column name that identifies a specified column in the specified table and a namespace identifier that identifies a set of relational databases. The computer system also receives an indication that identifies which type of encryption is to be applied when encrypting the column of data specified by the column name. The computer system then generates a policy column URI that includes a hierarchical string comprising the namespace identifier, the database schema name, the table name and the column name.