diff --git a/osu.Game/Database/OsuDbContext.cs b/osu.Game/Database/OsuDbContext.cs
index 928c355696..9c1413b93b 100644
--- a/osu.Game/Database/OsuDbContext.cs
+++ b/osu.Game/Database/OsuDbContext.cs
@@ -78,6 +78,7 @@ namespace osu.Game.Database
         {
             base.OnModelCreating(modelBuilder);
 
+            modelBuilder.Entity<BeatmapInfo>().HasIndex(b => b.OnlineBeatmapID).IsUnique();
             modelBuilder.Entity<BeatmapInfo>().HasIndex(b => b.MD5Hash).IsUnique();
             modelBuilder.Entity<BeatmapInfo>().HasIndex(b => b.Hash).IsUnique();