diff --git a/schema.sql b/schema.sql
index 469526a..bb76552 100644
--- a/schema.sql
+++ b/schema.sql
@@ -29,4 +29,5 @@ CREATE TABLE "flights" (
     "departure_date" NUMERIC NOT NULL,
     "arrival_date" NUMERIC NOT NULL,
     PRIMARY KEY("id")
+    FOREIGN KEY("airline") REFERENCES "airlines"("name"),
 )