diff --git a/src/db/mod.rs b/src/db/mod.rs
index b282e64..c95b92f 100644
--- a/src/db/mod.rs
+++ b/src/db/mod.rs
@@ -6,7 +6,8 @@ pub fn init(conn: &Connection) -> Result<()> {
             id INTEGER PRIMARY KEY,
             username TEXT,
             email TEXT,
-            password TEXT
+            password TEXT,
+            UNIQUE(username, email)
         )",
         (),
     )?;