Systems, methods, and devices for generating a secure join of database data are disclosed. A method includes determining data stored in a first account to be compared with data stored in a second account. The method includes determining a function for generating a secure join key, wherein the secure join key includes a hashed string that hashes one or more of a data entry of the first account and a data entry of the second account. The method includes providing the secure join key to the first account and/or the second account.