Fix all remaining db structure issues

osu.Game.Rulesets.Mania/Beatmaps/ManiaBeatmapConverter.cs

@@ -43,7 +43,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps
         {
             beatmap = original;
 
-            BeatmapDifficulty difficulty = original.BeatmapInfo.Difficulty;
+            BeatmapDifficulty difficulty = original.BeatmapInfo.BaseDifficulty;
 
             int seed = (int)Math.Round(difficulty.DrainRate + difficulty.CircleSize) * 20 + (int)(difficulty.OverallDifficulty * 41.2) + (int)Math.Round(difficulty.ApproachRate);
             random = new FastRandom(seed);

osu.Game.Rulesets.Mania/Beatmaps/Patterns/Legacy/DistanceObjectPatternGenerator.cs

@@ -47,7 +47,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
             // The true distance, accounting for any repeats
             double distance = (distanceData?.Distance ?? 0) * repeatCount;
             // The velocity of the osu! hit object - calculated as the velocity of a slider
-            double osuVelocity = osu_base_scoring_distance * beatmap.BeatmapInfo.Difficulty.SliderMultiplier * difficultyPoint.SpeedMultiplier / timingPoint.BeatLength;
+            double osuVelocity = osu_base_scoring_distance * beatmap.BeatmapInfo.BaseDifficulty.SliderMultiplier * difficultyPoint.SpeedMultiplier / timingPoint.BeatLength;
             // The duration of the osu! hit object
             double osuDuration = distance / osuVelocity;
 

osu.Game.Rulesets.Mania/Beatmaps/Patterns/Legacy/PatternGenerator.cs

@@ -104,7 +104,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
                 if (drainTime == 0)
                     drainTime = 10000;
 
-                BeatmapDifficulty difficulty = Beatmap.BeatmapInfo.Difficulty;
+                BeatmapDifficulty difficulty = Beatmap.BeatmapInfo.BaseDifficulty;
                 conversionDifficulty = ((difficulty.DrainRate + MathHelper.Clamp(difficulty.ApproachRate, 4, 7)) / 1.5 + Beatmap.HitObjects.Count / drainTime * 9f) / 38f * 5f / 1.15;
                 conversionDifficulty = Math.Min(conversionDifficulty.Value, 12);
 

osu.Game.Rulesets.Mania/ManiaDifficultyCalculator.cs

@@ -21,6 +21,6 @@ namespace osu.Game.Rulesets.Mania
             return 0;
         }
 
-        protected override BeatmapConverter<ManiaHitObject> CreateBeatmapConverter() => new ManiaBeatmapConverter(true, (int)Math.Max(1, Math.Round(Beatmap.BeatmapInfo.Difficulty.CircleSize)));
+        protected override BeatmapConverter<ManiaHitObject> CreateBeatmapConverter() => new ManiaBeatmapConverter(true, (int)Math.Max(1, Math.Round(Beatmap.BeatmapInfo.BaseDifficulty.CircleSize)));
     }
 }

osu.Game.Rulesets.Mania/Scoring/ManiaScoreProcessor.cs

@@ -100,7 +100,7 @@ namespace osu.Game.Rulesets.Mania.Scoring
 
         protected override void SimulateAutoplay(Beatmap<ManiaHitObject> beatmap)
         {
-            BeatmapDifficulty difficulty = beatmap.BeatmapInfo.Difficulty;
+            BeatmapDifficulty difficulty = beatmap.BeatmapInfo.BaseDifficulty;
             hpMultiplier = BeatmapDifficulty.DifficultyRange(difficulty.DrainRate, hp_multiplier_min, hp_multiplier_mid, hp_multiplier_max);
             hpMissMultiplier = BeatmapDifficulty.DifficultyRange(difficulty.DrainRate, hp_multiplier_miss_min, hp_multiplier_miss_mid, hp_multiplier_miss_max);
 

osu.Game.Rulesets.Mania/UI/ManiaRulesetContainer.cs

@@ -88,18 +88,18 @@ namespace osu.Game.Rulesets.Mania.UI
         protected override BeatmapConverter<ManiaHitObject> CreateBeatmapConverter()
         {
             if (IsForCurrentRuleset)
-                AvailableColumns = (int)Math.Max(1, Math.Round(WorkingBeatmap.BeatmapInfo.Difficulty.CircleSize));
+                AvailableColumns = (int)Math.Max(1, Math.Round(WorkingBeatmap.BeatmapInfo.BaseDifficulty.CircleSize));
             else
             {
                 float percentSliderOrSpinner = (float)WorkingBeatmap.Beatmap.HitObjects.Count(h => h is IHasEndTime) / WorkingBeatmap.Beatmap.HitObjects.Count;
                 if (percentSliderOrSpinner < 0.2)
                     AvailableColumns = 7;
-                else if (percentSliderOrSpinner < 0.3 || Math.Round(WorkingBeatmap.BeatmapInfo.Difficulty.CircleSize) >= 5)
+                else if (percentSliderOrSpinner < 0.3 || Math.Round(WorkingBeatmap.BeatmapInfo.BaseDifficulty.CircleSize) >= 5)
-                    AvailableColumns = Math.Round(WorkingBeatmap.BeatmapInfo.Difficulty.OverallDifficulty) > 5 ? 7 : 6;
+                    AvailableColumns = Math.Round(WorkingBeatmap.BeatmapInfo.BaseDifficulty.OverallDifficulty) > 5 ? 7 : 6;
                 else if (percentSliderOrSpinner > 0.6)
-                    AvailableColumns = Math.Round(WorkingBeatmap.BeatmapInfo.Difficulty.OverallDifficulty) > 4 ? 5 : 4;
+                    AvailableColumns = Math.Round(WorkingBeatmap.BeatmapInfo.BaseDifficulty.OverallDifficulty) > 4 ? 5 : 4;
                 else
-                    AvailableColumns = Math.Max(4, Math.Min((int)Math.Round(WorkingBeatmap.BeatmapInfo.Difficulty.OverallDifficulty) + 1, 7));
+                    AvailableColumns = Math.Max(4, Math.Min((int)Math.Round(WorkingBeatmap.BeatmapInfo.BaseDifficulty.OverallDifficulty) + 1, 7));
             }
 
             return new ManiaBeatmapConverter(IsForCurrentRuleset, AvailableColumns);

osu.Game.Rulesets.Osu/Scoring/OsuScoreProcessor.cs

@@ -28,7 +28,7 @@ namespace osu.Game.Rulesets.Osu.Scoring
 
         protected override void SimulateAutoplay(Beatmap<OsuHitObject> beatmap)
         {
-            hpDrainRate = beatmap.BeatmapInfo.Difficulty.DrainRate;
+            hpDrainRate = beatmap.BeatmapInfo.BaseDifficulty.DrainRate;
 
             foreach (var obj in beatmap.HitObjects)
             {

osu.Game.Rulesets.Osu/UI/Cursor/GameplayCursor.cs

@@ -125,7 +125,7 @@ namespace osu.Game.Rulesets.Osu.UI.Cursor
                 if (autoCursorScale && beatmap.Value != null)
                 {
                     // if we have a beatmap available, let's get its circle size to figure out an automatic cursor scale modifier.
-                    scale *= (float)(1 - 0.7 * (1 + beatmap.Value.BeatmapInfo.Difficulty.CircleSize - BeatmapDifficulty.DEFAULT_DIFFICULTY) / BeatmapDifficulty.DEFAULT_DIFFICULTY);
+                    scale *= (float)(1 - 0.7 * (1 + beatmap.Value.BeatmapInfo.BaseDifficulty.CircleSize - BeatmapDifficulty.DEFAULT_DIFFICULTY) / BeatmapDifficulty.DEFAULT_DIFFICULTY);
                 }
 
                 cursorContainer.Scale = new Vector2(scale);

osu.Game.Rulesets.Taiko/Beatmaps/TaikoBeatmapConverter.cs

@@ -51,7 +51,7 @@ namespace osu.Game.Rulesets.Taiko.Beatmaps
         {
             // Rewrite the beatmap info to add the slider velocity multiplier
             BeatmapInfo info = original.BeatmapInfo.DeepClone();
-            info.Difficulty.SliderMultiplier *= legacy_velocity_multiplier;
+            info.BaseDifficulty.SliderMultiplier *= legacy_velocity_multiplier;
 
             Beatmap<TaikoHitObject> converted = base.ConvertBeatmap(original);
 
@@ -96,7 +96,7 @@ namespace osu.Game.Rulesets.Taiko.Beatmaps
                 double distance = distanceData.Distance * repeats * legacy_velocity_multiplier;
 
                 // The velocity of the taiko hit object - calculated as the velocity of a drum roll
-                double taikoVelocity = taiko_base_distance * beatmap.BeatmapInfo.Difficulty.SliderMultiplier * legacy_velocity_multiplier / speedAdjustedBeatLength;
+                double taikoVelocity = taiko_base_distance * beatmap.BeatmapInfo.BaseDifficulty.SliderMultiplier * legacy_velocity_multiplier / speedAdjustedBeatLength;
                 // The duration of the taiko hit object
                 double taikoDuration = distance / taikoVelocity;
 
@@ -106,12 +106,12 @@ namespace osu.Game.Rulesets.Taiko.Beatmaps
                     speedAdjustedBeatLength *= speedAdjustment;
 
                 // The velocity of the osu! hit object - calculated as the velocity of a slider
-                double osuVelocity = osu_base_scoring_distance * beatmap.BeatmapInfo.Difficulty.SliderMultiplier * legacy_velocity_multiplier / speedAdjustedBeatLength;
+                double osuVelocity = osu_base_scoring_distance * beatmap.BeatmapInfo.BaseDifficulty.SliderMultiplier * legacy_velocity_multiplier / speedAdjustedBeatLength;
                 // The duration of the osu! hit object
                 double osuDuration = distance / osuVelocity;
 
                 // If the drum roll is to be split into hit circles, assume the ticks are 1/8 spaced within the duration of one beat
-                double tickSpacing = Math.Min(speedAdjustedBeatLength / beatmap.BeatmapInfo.Difficulty.SliderTickRate, taikoDuration / repeats);
+                double tickSpacing = Math.Min(speedAdjustedBeatLength / beatmap.BeatmapInfo.BaseDifficulty.SliderTickRate, taikoDuration / repeats);
 
                 if (!isForCurrentRuleset && tickSpacing > 0 && osuDuration < 2 * speedAdjustedBeatLength)
                 {
@@ -154,13 +154,13 @@ namespace osu.Game.Rulesets.Taiko.Beatmaps
                         Samples = obj.Samples,
                         IsStrong = strong,
                         Duration = taikoDuration,
-                        TickRate = beatmap.BeatmapInfo.Difficulty.SliderTickRate == 3 ? 3 : 4,
+                        TickRate = beatmap.BeatmapInfo.BaseDifficulty.SliderTickRate == 3 ? 3 : 4,
                     };
                 }
             }
             else if (endTimeData != null)
             {
-                double hitMultiplier = BeatmapDifficulty.DifficultyRange(beatmap.BeatmapInfo.Difficulty.OverallDifficulty, 3, 5, 7.5) * swell_hit_multiplier;
+                double hitMultiplier = BeatmapDifficulty.DifficultyRange(beatmap.BeatmapInfo.BaseDifficulty.OverallDifficulty, 3, 5, 7.5) * swell_hit_multiplier;
 
                 yield return new Swell
                 {

osu.Game.Rulesets.Taiko/Scoring/TaikoScoreProcessor.cs

@@ -71,12 +71,12 @@ namespace osu.Game.Rulesets.Taiko.Scoring
 
         protected override void SimulateAutoplay(Beatmap<TaikoHitObject> beatmap)
         {
-            double hpMultiplierNormal = 1 / (hp_hit_great * beatmap.HitObjects.FindAll(o => o is Hit).Count * BeatmapDifficulty.DifficultyRange(beatmap.BeatmapInfo.Difficulty.DrainRate, 0.5, 0.75, 0.98));
+            double hpMultiplierNormal = 1 / (hp_hit_great * beatmap.HitObjects.FindAll(o => o is Hit).Count * BeatmapDifficulty.DifficultyRange(beatmap.BeatmapInfo.BaseDifficulty.DrainRate, 0.5, 0.75, 0.98));
 
             hpIncreaseTick = hp_hit_tick;
             hpIncreaseGreat = hpMultiplierNormal * hp_hit_great;
             hpIncreaseGood = hpMultiplierNormal * hp_hit_good;
-            hpIncreaseMiss = BeatmapDifficulty.DifficultyRange(beatmap.BeatmapInfo.Difficulty.DrainRate, hp_miss_min, hp_miss_mid, hp_miss_max);
+            hpIncreaseMiss = BeatmapDifficulty.DifficultyRange(beatmap.BeatmapInfo.BaseDifficulty.DrainRate, hp_miss_min, hp_miss_mid, hp_miss_max);
 
             foreach (var obj in beatmap.HitObjects)
             {

osu.Game.Rulesets.Taiko/Tests/TestCaseTaikoPlayfield.cs

@@ -67,7 +67,7 @@ namespace osu.Game.Rulesets.Taiko.Tests
                 HitObjects = new List<HitObject> { new CentreHit() },
                 BeatmapInfo = new BeatmapInfo
                 {
-                    Difficulty = new BeatmapDifficulty(),
+                    BaseDifficulty = new BeatmapDifficulty(),
                     Metadata = new BeatmapMetadata
                     {
                         Artist = @"Unknown",

osu.Game.Rulesets.Taiko/UI/TaikoRulesetContainer.cs

@@ -63,7 +63,7 @@ namespace osu.Game.Rulesets.Taiko.UI
                     StartTime = time,
                 };
 
-                barLine.ApplyDefaults(Beatmap.ControlPointInfo, Beatmap.BeatmapInfo.Difficulty);
+                barLine.ApplyDefaults(Beatmap.ControlPointInfo, Beatmap.BeatmapInfo.BaseDifficulty);
 
                 bool isMajor = currentBeat % (int)currentPoint.TimeSignature == 0;
                 Playfield.Add(isMajor ? new DrawableBarLineMajor(barLine) : new DrawableBarLine(barLine));

osu.Game.Tests/Beatmaps/Formats/OsuLegacyDecoderTest.cs

@@ -85,7 +85,7 @@ namespace osu.Game.Tests.Beatmaps.Formats
             using (var stream = Resource.OpenResource("Soleily - Renatus (Gamu) [Insane].osu"))
             {
                 var beatmap = decoder.Decode(new StreamReader(stream));
-                var difficulty = beatmap.BeatmapInfo.Difficulty;
+                var difficulty = beatmap.BeatmapInfo.BaseDifficulty;
                 Assert.AreEqual(6.5f, difficulty.DrainRate);
                 Assert.AreEqual(4, difficulty.CircleSize);
                 Assert.AreEqual(8, difficulty.OverallDifficulty);

osu.Game/Beatmaps/Beatmap.cs

@@ -72,7 +72,7 @@ namespace osu.Game.Beatmaps
                         AuthorString = @"Unknown Creator",
                     },
                     Version = @"Normal",
-                    Difficulty = new BeatmapDifficulty()
+                    BaseDifficulty = new BeatmapDifficulty()
                 };
             }
         }

osu.Game/Beatmaps/BeatmapDifficulty.cs

@@ -15,8 +15,6 @@ namespace osu.Game.Beatmaps
         [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
         public int ID { get; set; }
 
-        public int BeatmapInfoID { get; set; }
-
         public float DrainRate { get; set; } = DEFAULT_DIFFICULTY;
         public float CircleSize { get; set; } = DEFAULT_DIFFICULTY;
         public float OverallDifficulty { get; set; } = DEFAULT_DIFFICULTY;

osu.Game/Beatmaps/BeatmapInfo.cs

@@ -20,7 +20,6 @@ namespace osu.Game.Beatmaps
         public int BeatmapVersion;
 
         [JsonProperty("id")]
-        [NotMapped]
         public int? OnlineBeatmapID { get; set; }
 
         [JsonProperty("beatmapset_id")]
@@ -36,8 +35,7 @@ namespace osu.Game.Beatmaps
 
         public int BaseDifficultyID { get; set; }
 
-        [Required]
+        public BeatmapDifficulty BaseDifficulty { get; set; }
-        public BeatmapDifficulty Difficulty { get; set; }
 
         [NotMapped]
         public BeatmapMetrics Metrics { get; set; }
@@ -55,7 +53,6 @@ namespace osu.Game.Beatmaps
         /// <summary>
         /// MD5 is kept for legacy support (matching against replays, osu-web-10 etc.).
         /// </summary>
-        [NotMapped]
         [JsonProperty("file_md5")]
         public string MD5Hash { get; set; }
 

osu.Game/Beatmaps/BeatmapMetadata.cs

@@ -1,6 +1,7 @@
 // Copyright (c) 2007-2017 ppy Pty Ltd <contact@ppy.sh>.
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
+using System.Collections.Generic;
 using System.ComponentModel.DataAnnotations.Schema;
 using System.Linq;
 using Newtonsoft.Json;
@@ -16,19 +17,14 @@ namespace osu.Game.Beatmaps
         [NotMapped]
         public int? OnlineBeatmapSetID { get; set; }
 
-        public int? BeatmapSetInfoID { get; set; }
-
-        public BeatmapSetInfo BeatmapSetInfo { get; set; }
-
-        public int? BeatmapInfoID { get; set; }
-
-        public BeatmapInfo BeatmapInfo { get; set; }
-
         public string Title { get; set; }
         public string TitleUnicode { get; set; }
         public string Artist { get; set; }
         public string ArtistUnicode { get; set; }
 
+        public List<BeatmapInfo> Beatmaps { get; set; }
+        public List<BeatmapSetInfo> BeatmapSets { get; set; }
+
         /// <summary>
         /// Helper property to deserialize a username to <see cref="User"/>.
         /// </summary>

osu.Game/Beatmaps/BeatmapStore.cs

@@ -137,7 +137,7 @@ namespace osu.Game.Beatmaps
         public IEnumerable<BeatmapSetInfo> BeatmapSets => GetContext().BeatmapSetInfo
                                                                       .Include(s => s.Metadata)
                                                                       .Include(s => s.Beatmaps).ThenInclude(s => s.Ruleset)
-                                                                      .Include(s => s.Beatmaps).ThenInclude(b => b.Difficulty)
+                                                                      .Include(s => s.Beatmaps).ThenInclude(b => b.BaseDifficulty)
                                                                       .Include(s => s.Beatmaps).ThenInclude(b => b.Metadata)
                                                                       .Include(s => s.Files).ThenInclude(f => f.FileInfo);
 
@@ -145,6 +145,6 @@ namespace osu.Game.Beatmaps
                                                                 .Include(b => b.BeatmapSet).ThenInclude(s => s.Metadata)
                                                                 .Include(b => b.Metadata)
                                                                 .Include(b => b.Ruleset)
-                                                                .Include(b => b.Difficulty);
+                                                                .Include(b => b.BaseDifficulty);
     }
 }

osu.Game/Beatmaps/DifficultyCalculator.cs

@@ -40,7 +40,7 @@ namespace osu.Game.Beatmaps
             Objects = CreateBeatmapConverter().Convert(beatmap).HitObjects;
 
             foreach (var h in Objects)
-                h.ApplyDefaults(beatmap.ControlPointInfo, beatmap.BeatmapInfo.Difficulty);
+                h.ApplyDefaults(beatmap.ControlPointInfo, beatmap.BeatmapInfo.BaseDifficulty);
 
             PreprocessHitObjects();
         }

osu.Game/Beatmaps/DummyWorkingBeatmap.cs

@@ -25,7 +25,7 @@ namespace osu.Game.Beatmaps
                     AuthorString = "no one",
                 },
                 BeatmapSet = new BeatmapSetInfo(),
-                Difficulty = new BeatmapDifficulty
+                BaseDifficulty = new BeatmapDifficulty
                 {
                     DrainRate = 0,
                     CircleSize = 0,

osu.Game/Beatmaps/Formats/BeatmapDecoder.cs

@@ -49,7 +49,7 @@ namespace osu.Game.Beatmaps.Formats
                 BeatmapInfo = new BeatmapInfo
                 {
                     Metadata = new BeatmapMetadata(),
-                    Difficulty = new BeatmapDifficulty(),
+                    BaseDifficulty = new BeatmapDifficulty(),
                 },
             };
 

osu.Game/Beatmaps/Formats/OsuLegacyDecoder.cs

@@ -196,7 +196,7 @@ namespace osu.Game.Beatmaps.Formats
         {
             var pair = splitKeyVal(line, ':');
 
-            var difficulty = beatmap.BeatmapInfo.Difficulty;
+            var difficulty = beatmap.BeatmapInfo.BaseDifficulty;
             switch (pair.Key)
             {
                 case @"HPDrainRate":
@@ -674,7 +674,7 @@ namespace osu.Game.Beatmaps.Formats
             }
 
             foreach (var hitObject in beatmap.HitObjects)
-                hitObject.ApplyDefaults(beatmap.ControlPointInfo, beatmap.BeatmapInfo.Difficulty);
+                hitObject.ApplyDefaults(beatmap.ControlPointInfo, beatmap.BeatmapInfo.BaseDifficulty);
         }
 
         private KeyValuePair<string, string> splitKeyVal(string line, char separator)

osu.Game/Database/OsuDbContext.cs

@@ -65,20 +65,22 @@ namespace osu.Game.Database
         protected override void OnModelCreating(ModelBuilder modelBuilder)
         {
             base.OnModelCreating(modelBuilder);
+
             modelBuilder.Entity<BeatmapInfo>().HasIndex(b => b.MD5Hash);
             modelBuilder.Entity<BeatmapInfo>().HasIndex(b => b.Hash);
+
             modelBuilder.Entity<BeatmapSetInfo>().HasIndex(b => b.DeletePending);
             modelBuilder.Entity<BeatmapSetInfo>().HasIndex(b => b.Hash);
+
             modelBuilder.Entity<DatabasedKeyBinding>().HasIndex(b => b.Variant);
             modelBuilder.Entity<DatabasedKeyBinding>().HasIndex(b => b.IntAction);
+
             modelBuilder.Entity<FileInfo>().HasIndex(b => b.Hash).IsUnique();
             modelBuilder.Entity<FileInfo>().HasIndex(b => b.ReferenceCount);
-            modelBuilder.Entity<RulesetInfo>().HasIndex(b => b.Name).IsUnique();
+
-            modelBuilder.Entity<RulesetInfo>().HasIndex(b => b.InstantiationInfo).IsUnique();
             modelBuilder.Entity<RulesetInfo>().HasIndex(b => b.Available);
 
-            modelBuilder.Entity<BeatmapMetadata>().HasOne(m => m.BeatmapSetInfo).WithOne(s => s.Metadata).OnDelete(DeleteBehavior.Cascade);
+            modelBuilder.Entity<BeatmapInfo>().HasOne(b => b.BaseDifficulty);
-            modelBuilder.Entity<BeatmapMetadata>().HasOne(m => m.BeatmapInfo).WithOne(b => b.Metadata).OnDelete(DeleteBehavior.Cascade);
         }
 
         private class OsuDbLoggerFactory : ILoggerFactory

osu.Game/Migrations/20171019041408_InitialCreate.Designer.cs

@@ -10,7 +10,7 @@ using System;
 namespace osu.Game.Migrations
 {
     [DbContext(typeof(OsuDbContext))]
-    [Migration("20171018125509_InitialCreate")]
+    [Migration("20171019041408_InitialCreate")]
     partial class InitialCreate
     {
         protected override void BuildTargetModel(ModelBuilder modelBuilder)
@@ -26,8 +26,6 @@ namespace osu.Game.Migrations
 
                     b.Property<float>("ApproachRate");
 
-                    b.Property<int>("BeatmapInfoID");
-
                     b.Property<float>("CircleSize");
 
                     b.Property<float>("DrainRate");
@@ -40,9 +38,6 @@ namespace osu.Game.Migrations
 
                     b.HasKey("ID");
 
-                    b.HasIndex("BeatmapInfoID")
-                        .IsUnique();
-
                     b.ToTable("BeatmapDifficulty");
                 });
 
@@ -73,6 +68,10 @@ namespace osu.Game.Migrations
 
                     b.Property<string>("MD5Hash");
 
+                    b.Property<int?>("MetadataID");
+
+                    b.Property<int?>("OnlineBeatmapID");
+
                     b.Property<string>("Path");
 
                     b.Property<int>("RulesetID");
@@ -93,12 +92,16 @@ namespace osu.Game.Migrations
 
                     b.HasKey("ID");
 
+                    b.HasIndex("BaseDifficultyID");
+
                     b.HasIndex("BeatmapSetInfoID");
 
                     b.HasIndex("Hash");
 
                     b.HasIndex("MD5Hash");
 
+                    b.HasIndex("MetadataID");
+
                     b.HasIndex("RulesetID");
 
                     b.ToTable("BeatmapInfo");
@@ -120,10 +123,6 @@ namespace osu.Game.Migrations
 
                     b.Property<string>("BackgroundFile");
 
-                    b.Property<int?>("BeatmapInfoID");
-
-                    b.Property<int?>("BeatmapSetInfoID");
-
                     b.Property<int>("PreviewTime");
 
                     b.Property<string>("Source");
@@ -136,12 +135,6 @@ namespace osu.Game.Migrations
 
                     b.HasKey("ID");
 
-                    b.HasIndex("BeatmapInfoID")
-                        .IsUnique();
-
-                    b.HasIndex("BeatmapSetInfoID")
-                        .IsUnique();
-
                     b.ToTable("BeatmapMetadata");
                 });
 
@@ -175,6 +168,8 @@ namespace osu.Game.Migrations
 
                     b.Property<string>("Hash");
 
+                    b.Property<int?>("MetadataID");
+
                     b.Property<int?>("OnlineBeatmapSetID");
 
                     b.Property<bool>("Protected");
@@ -185,6 +180,8 @@ namespace osu.Game.Migrations
 
                     b.HasIndex("Hash");
 
+                    b.HasIndex("MetadataID");
+
                     b.ToTable("BeatmapSetInfo");
                 });
 
@@ -246,49 +243,31 @@ namespace osu.Game.Migrations
 
                     b.HasIndex("Available");
 
-                    b.HasIndex("InstantiationInfo")
-                        .IsUnique();
-
-                    b.HasIndex("Name")
-                        .IsUnique();
-
                     b.ToTable("RulesetInfo");
                 });
 
-            modelBuilder.Entity("osu.Game.Beatmaps.BeatmapDifficulty", b =>
-                {
-                    b.HasOne("osu.Game.Beatmaps.BeatmapInfo")
-                        .WithOne("Difficulty")
-                        .HasForeignKey("osu.Game.Beatmaps.BeatmapDifficulty", "BeatmapInfoID")
-                        .OnDelete(DeleteBehavior.Cascade);
-                });
-
             modelBuilder.Entity("osu.Game.Beatmaps.BeatmapInfo", b =>
                 {
+                    b.HasOne("osu.Game.Beatmaps.BeatmapDifficulty", "BaseDifficulty")
+                        .WithMany()
+                        .HasForeignKey("BaseDifficultyID")
+                        .OnDelete(DeleteBehavior.Cascade);
+
                     b.HasOne("osu.Game.Beatmaps.BeatmapSetInfo", "BeatmapSet")
                         .WithMany("Beatmaps")
                         .HasForeignKey("BeatmapSetInfoID")
                         .OnDelete(DeleteBehavior.Cascade);
 
+                    b.HasOne("osu.Game.Beatmaps.BeatmapMetadata", "Metadata")
+                        .WithMany("Beatmaps")
+                        .HasForeignKey("MetadataID");
+
                     b.HasOne("osu.Game.Rulesets.RulesetInfo", "Ruleset")
                         .WithMany()
                         .HasForeignKey("RulesetID")
                         .OnDelete(DeleteBehavior.Cascade);
                 });
 
-            modelBuilder.Entity("osu.Game.Beatmaps.BeatmapMetadata", b =>
-                {
-                    b.HasOne("osu.Game.Beatmaps.BeatmapInfo", "BeatmapInfo")
-                        .WithOne("Metadata")
-                        .HasForeignKey("osu.Game.Beatmaps.BeatmapMetadata", "BeatmapInfoID")
-                        .OnDelete(DeleteBehavior.Cascade);
-
-                    b.HasOne("osu.Game.Beatmaps.BeatmapSetInfo", "BeatmapSetInfo")
-                        .WithOne("Metadata")
-                        .HasForeignKey("osu.Game.Beatmaps.BeatmapMetadata", "BeatmapSetInfoID")
-                        .OnDelete(DeleteBehavior.Cascade);
-                });
-
             modelBuilder.Entity("osu.Game.Beatmaps.BeatmapSetFileInfo", b =>
                 {
                     b.HasOne("osu.Game.Beatmaps.BeatmapSetInfo")
@@ -301,6 +280,13 @@ namespace osu.Game.Migrations
                         .HasForeignKey("FileInfoID")
                         .OnDelete(DeleteBehavior.Cascade);
                 });
+
+            modelBuilder.Entity("osu.Game.Beatmaps.BeatmapSetInfo", b =>
+                {
+                    b.HasOne("osu.Game.Beatmaps.BeatmapMetadata", "Metadata")
+                        .WithMany("BeatmapSets")
+                        .HasForeignKey("MetadataID");
+                });
 #pragma warning restore 612, 618
         }
     }

osu.Game/Migrations/20171019041408_InitialCreate.cs

@@ -9,19 +9,43 @@ namespace osu.Game.Migrations
         protected override void Up(MigrationBuilder migrationBuilder)
         {
             migrationBuilder.CreateTable(
-                name: "BeatmapSetInfo",
+                name: "BeatmapDifficulty",
                 columns: table => new
                 {
                     ID = table.Column<int>(type: "INTEGER", nullable: false)
                         .Annotation("Sqlite:Autoincrement", true),
-                    DeletePending = table.Column<bool>(type: "INTEGER", nullable: false),
+                    ApproachRate = table.Column<float>(type: "REAL", nullable: false),
-                    Hash = table.Column<string>(type: "TEXT", nullable: true),
+                    CircleSize = table.Column<float>(type: "REAL", nullable: false),
-                    OnlineBeatmapSetID = table.Column<int>(type: "INTEGER", nullable: true),
+                    DrainRate = table.Column<float>(type: "REAL", nullable: false),
-                    Protected = table.Column<bool>(type: "INTEGER", nullable: false)
+                    OverallDifficulty = table.Column<float>(type: "REAL", nullable: false),
+                    SliderMultiplier = table.Column<float>(type: "REAL", nullable: false),
+                    SliderTickRate = table.Column<float>(type: "REAL", nullable: false)
                 },
                 constraints: table =>
                 {
-                    table.PrimaryKey("PK_BeatmapSetInfo", x => x.ID);
+                    table.PrimaryKey("PK_BeatmapDifficulty", x => x.ID);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "BeatmapMetadata",
+                columns: table => new
+                {
+                    ID = table.Column<int>(type: "INTEGER", nullable: false)
+                        .Annotation("Sqlite:Autoincrement", true),
+                    Artist = table.Column<string>(type: "TEXT", nullable: true),
+                    ArtistUnicode = table.Column<string>(type: "TEXT", nullable: true),
+                    AudioFile = table.Column<string>(type: "TEXT", nullable: true),
+                    Author = table.Column<string>(type: "TEXT", nullable: true),
+                    BackgroundFile = table.Column<string>(type: "TEXT", nullable: true),
+                    PreviewTime = table.Column<int>(type: "INTEGER", nullable: false),
+                    Source = table.Column<string>(type: "TEXT", nullable: true),
+                    Tags = table.Column<string>(type: "TEXT", nullable: true),
+                    Title = table.Column<string>(type: "TEXT", nullable: true),
+                    TitleUnicode = table.Column<string>(type: "TEXT", nullable: true)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_BeatmapMetadata", x => x.ID);
                 });
 
             migrationBuilder.CreateTable(
@@ -69,6 +93,87 @@ namespace osu.Game.Migrations
                     table.PrimaryKey("PK_RulesetInfo", x => x.ID);
                 });
 
+            migrationBuilder.CreateTable(
+                name: "BeatmapSetInfo",
+                columns: table => new
+                {
+                    ID = table.Column<int>(type: "INTEGER", nullable: false)
+                        .Annotation("Sqlite:Autoincrement", true),
+                    DeletePending = table.Column<bool>(type: "INTEGER", nullable: false),
+                    Hash = table.Column<string>(type: "TEXT", nullable: true),
+                    MetadataID = table.Column<int>(type: "INTEGER", nullable: true),
+                    OnlineBeatmapSetID = table.Column<int>(type: "INTEGER", nullable: true),
+                    Protected = table.Column<bool>(type: "INTEGER", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_BeatmapSetInfo", x => x.ID);
+                    table.ForeignKey(
+                        name: "FK_BeatmapSetInfo_BeatmapMetadata_MetadataID",
+                        column: x => x.MetadataID,
+                        principalTable: "BeatmapMetadata",
+                        principalColumn: "ID",
+                        onDelete: ReferentialAction.Restrict);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "BeatmapInfo",
+                columns: table => new
+                {
+                    ID = table.Column<int>(type: "INTEGER", nullable: false)
+                        .Annotation("Sqlite:Autoincrement", true),
+                    AudioLeadIn = table.Column<int>(type: "INTEGER", nullable: false),
+                    BaseDifficultyID = table.Column<int>(type: "INTEGER", nullable: false),
+                    BeatDivisor = table.Column<int>(type: "INTEGER", nullable: false),
+                    BeatmapSetInfoID = table.Column<int>(type: "INTEGER", nullable: false),
+                    Countdown = table.Column<bool>(type: "INTEGER", nullable: false),
+                    DistanceSpacing = table.Column<double>(type: "REAL", nullable: false),
+                    GridSize = table.Column<int>(type: "INTEGER", nullable: false),
+                    Hash = table.Column<string>(type: "TEXT", nullable: true),
+                    Hidden = table.Column<bool>(type: "INTEGER", nullable: false),
+                    LetterboxInBreaks = table.Column<bool>(type: "INTEGER", nullable: false),
+                    MD5Hash = table.Column<string>(type: "TEXT", nullable: true),
+                    MetadataID = table.Column<int>(type: "INTEGER", nullable: true),
+                    OnlineBeatmapID = table.Column<int>(type: "INTEGER", nullable: true),
+                    Path = table.Column<string>(type: "TEXT", nullable: true),
+                    RulesetID = table.Column<int>(type: "INTEGER", nullable: false),
+                    SpecialStyle = table.Column<bool>(type: "INTEGER", nullable: false),
+                    StackLeniency = table.Column<float>(type: "REAL", nullable: false),
+                    StarDifficulty = table.Column<double>(type: "REAL", nullable: false),
+                    StoredBookmarks = table.Column<string>(type: "TEXT", nullable: true),
+                    TimelineZoom = table.Column<double>(type: "REAL", nullable: false),
+                    Version = table.Column<string>(type: "TEXT", nullable: true),
+                    WidescreenStoryboard = table.Column<bool>(type: "INTEGER", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_BeatmapInfo", x => x.ID);
+                    table.ForeignKey(
+                        name: "FK_BeatmapInfo_BeatmapDifficulty_BaseDifficultyID",
+                        column: x => x.BaseDifficultyID,
+                        principalTable: "BeatmapDifficulty",
+                        principalColumn: "ID",
+                        onDelete: ReferentialAction.Cascade);
+                    table.ForeignKey(
+                        name: "FK_BeatmapInfo_BeatmapSetInfo_BeatmapSetInfoID",
+                        column: x => x.BeatmapSetInfoID,
+                        principalTable: "BeatmapSetInfo",
+                        principalColumn: "ID",
+                        onDelete: ReferentialAction.Cascade);
+                    table.ForeignKey(
+                        name: "FK_BeatmapInfo_BeatmapMetadata_MetadataID",
+                        column: x => x.MetadataID,
+                        principalTable: "BeatmapMetadata",
+                        principalColumn: "ID",
+                        onDelete: ReferentialAction.Restrict);
+                    table.ForeignKey(
+                        name: "FK_BeatmapInfo_RulesetInfo_RulesetID",
+                        column: x => x.RulesetID,
+                        principalTable: "RulesetInfo",
+                        principalColumn: "ID",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
             migrationBuilder.CreateTable(
                 name: "BeatmapSetFileInfo",
                 columns: table => new
@@ -96,116 +201,10 @@ namespace osu.Game.Migrations
                         onDelete: ReferentialAction.Cascade);
                 });
 
-            migrationBuilder.CreateTable(
-                name: "BeatmapInfo",
-                columns: table => new
-                {
-                    ID = table.Column<int>(type: "INTEGER", nullable: false)
-                        .Annotation("Sqlite:Autoincrement", true),
-                    AudioLeadIn = table.Column<int>(type: "INTEGER", nullable: false),
-                    BaseDifficultyID = table.Column<int>(type: "INTEGER", nullable: false),
-                    BeatDivisor = table.Column<int>(type: "INTEGER", nullable: false),
-                    BeatmapSetInfoID = table.Column<int>(type: "INTEGER", nullable: false),
-                    Countdown = table.Column<bool>(type: "INTEGER", nullable: false),
-                    DistanceSpacing = table.Column<double>(type: "REAL", nullable: false),
-                    GridSize = table.Column<int>(type: "INTEGER", nullable: false),
-                    Hash = table.Column<string>(type: "TEXT", nullable: true),
-                    Hidden = table.Column<bool>(type: "INTEGER", nullable: false),
-                    LetterboxInBreaks = table.Column<bool>(type: "INTEGER", nullable: false),
-                    MD5Hash = table.Column<string>(type: "TEXT", nullable: true),
-                    Path = table.Column<string>(type: "TEXT", nullable: true),
-                    RulesetID = table.Column<int>(type: "INTEGER", nullable: false),
-                    SpecialStyle = table.Column<bool>(type: "INTEGER", nullable: false),
-                    StackLeniency = table.Column<float>(type: "REAL", nullable: false),
-                    StarDifficulty = table.Column<double>(type: "REAL", nullable: false),
-                    StoredBookmarks = table.Column<string>(type: "TEXT", nullable: true),
-                    TimelineZoom = table.Column<double>(type: "REAL", nullable: false),
-                    Version = table.Column<string>(type: "TEXT", nullable: true),
-                    WidescreenStoryboard = table.Column<bool>(type: "INTEGER", nullable: false)
-                },
-                constraints: table =>
-                {
-                    table.PrimaryKey("PK_BeatmapInfo", x => x.ID);
-                    table.ForeignKey(
-                        name: "FK_BeatmapInfo_BeatmapSetInfo_BeatmapSetInfoID",
-                        column: x => x.BeatmapSetInfoID,
-                        principalTable: "BeatmapSetInfo",
-                        principalColumn: "ID",
-                        onDelete: ReferentialAction.Cascade);
-                    table.ForeignKey(
-                        name: "FK_BeatmapInfo_RulesetInfo_RulesetID",
-                        column: x => x.RulesetID,
-                        principalTable: "RulesetInfo",
-                        principalColumn: "ID",
-                        onDelete: ReferentialAction.Cascade);
-                });
-
-            migrationBuilder.CreateTable(
-                name: "BeatmapDifficulty",
-                columns: table => new
-                {
-                    ID = table.Column<int>(type: "INTEGER", nullable: false)
-                        .Annotation("Sqlite:Autoincrement", true),
-                    ApproachRate = table.Column<float>(type: "REAL", nullable: false),
-                    BeatmapInfoID = table.Column<int>(type: "INTEGER", nullable: false),
-                    CircleSize = table.Column<float>(type: "REAL", nullable: false),
-                    DrainRate = table.Column<float>(type: "REAL", nullable: false),
-                    OverallDifficulty = table.Column<float>(type: "REAL", nullable: false),
-                    SliderMultiplier = table.Column<float>(type: "REAL", nullable: false),
-                    SliderTickRate = table.Column<float>(type: "REAL", nullable: false)
-                },
-                constraints: table =>
-                {
-                    table.PrimaryKey("PK_BeatmapDifficulty", x => x.ID);
-                    table.ForeignKey(
-                        name: "FK_BeatmapDifficulty_BeatmapInfo_BeatmapInfoID",
-                        column: x => x.BeatmapInfoID,
-                        principalTable: "BeatmapInfo",
-                        principalColumn: "ID",
-                        onDelete: ReferentialAction.Cascade);
-                });
-
-            migrationBuilder.CreateTable(
-                name: "BeatmapMetadata",
-                columns: table => new
-                {
-                    ID = table.Column<int>(type: "INTEGER", nullable: false)
-                        .Annotation("Sqlite:Autoincrement", true),
-                    Artist = table.Column<string>(type: "TEXT", nullable: true),
-                    ArtistUnicode = table.Column<string>(type: "TEXT", nullable: true),
-                    AudioFile = table.Column<string>(type: "TEXT", nullable: true),
-                    Author = table.Column<string>(type: "TEXT", nullable: true),
-                    BackgroundFile = table.Column<string>(type: "TEXT", nullable: true),
-                    BeatmapInfoID = table.Column<int>(type: "INTEGER", nullable: true),
-                    BeatmapSetInfoID = table.Column<int>(type: "INTEGER", nullable: true),
-                    PreviewTime = table.Column<int>(type: "INTEGER", nullable: false),
-                    Source = table.Column<string>(type: "TEXT", nullable: true),
-                    Tags = table.Column<string>(type: "TEXT", nullable: true),
-                    Title = table.Column<string>(type: "TEXT", nullable: true),
-                    TitleUnicode = table.Column<string>(type: "TEXT", nullable: true)
-                },
-                constraints: table =>
-                {
-                    table.PrimaryKey("PK_BeatmapMetadata", x => x.ID);
-                    table.ForeignKey(
-                        name: "FK_BeatmapMetadata_BeatmapInfo_BeatmapInfoID",
-                        column: x => x.BeatmapInfoID,
-                        principalTable: "BeatmapInfo",
-                        principalColumn: "ID",
-                        onDelete: ReferentialAction.Cascade);
-                    table.ForeignKey(
-                        name: "FK_BeatmapMetadata_BeatmapSetInfo_BeatmapSetInfoID",
-                        column: x => x.BeatmapSetInfoID,
-                        principalTable: "BeatmapSetInfo",
-                        principalColumn: "ID",
-                        onDelete: ReferentialAction.Cascade);
-                });
-
             migrationBuilder.CreateIndex(
-                name: "IX_BeatmapDifficulty_BeatmapInfoID",
+                name: "IX_BeatmapInfo_BaseDifficultyID",
-                table: "BeatmapDifficulty",
+                table: "BeatmapInfo",
-                column: "BeatmapInfoID",
+                column: "BaseDifficultyID");
-                unique: true);
 
             migrationBuilder.CreateIndex(
                 name: "IX_BeatmapInfo_BeatmapSetInfoID",
@@ -222,23 +221,16 @@ namespace osu.Game.Migrations
                 table: "BeatmapInfo",
                 column: "MD5Hash");
 
+            migrationBuilder.CreateIndex(
+                name: "IX_BeatmapInfo_MetadataID",
+                table: "BeatmapInfo",
+                column: "MetadataID");
+
             migrationBuilder.CreateIndex(
                 name: "IX_BeatmapInfo_RulesetID",
                 table: "BeatmapInfo",
                 column: "RulesetID");
 
-            migrationBuilder.CreateIndex(
-                name: "IX_BeatmapMetadata_BeatmapInfoID",
-                table: "BeatmapMetadata",
-                column: "BeatmapInfoID",
-                unique: true);
-
-            migrationBuilder.CreateIndex(
-                name: "IX_BeatmapMetadata_BeatmapSetInfoID",
-                table: "BeatmapMetadata",
-                column: "BeatmapSetInfoID",
-                unique: true);
-
             migrationBuilder.CreateIndex(
                 name: "IX_BeatmapSetFileInfo_BeatmapSetInfoID",
                 table: "BeatmapSetFileInfo",
@@ -259,6 +251,11 @@ namespace osu.Game.Migrations
                 table: "BeatmapSetInfo",
                 column: "Hash");
 
+            migrationBuilder.CreateIndex(
+                name: "IX_BeatmapSetInfo_MetadataID",
+                table: "BeatmapSetInfo",
+                column: "MetadataID");
+
             migrationBuilder.CreateIndex(
                 name: "IX_FileInfo_Hash",
                 table: "FileInfo",
@@ -284,27 +281,12 @@ namespace osu.Game.Migrations
                 name: "IX_RulesetInfo_Available",
                 table: "RulesetInfo",
                 column: "Available");
-
-            migrationBuilder.CreateIndex(
-                name: "IX_RulesetInfo_InstantiationInfo",
-                table: "RulesetInfo",
-                column: "InstantiationInfo",
-                unique: true);
-
-            migrationBuilder.CreateIndex(
-                name: "IX_RulesetInfo_Name",
-                table: "RulesetInfo",
-                column: "Name",
-                unique: true);
         }
 
         protected override void Down(MigrationBuilder migrationBuilder)
         {
             migrationBuilder.DropTable(
-                name: "BeatmapDifficulty");
+                name: "BeatmapInfo");
-
-            migrationBuilder.DropTable(
-                name: "BeatmapMetadata");
 
             migrationBuilder.DropTable(
                 name: "BeatmapSetFileInfo");
@@ -313,16 +295,19 @@ namespace osu.Game.Migrations
                 name: "KeyBinding");
 
             migrationBuilder.DropTable(
-                name: "BeatmapInfo");
+                name: "BeatmapDifficulty");
 
             migrationBuilder.DropTable(
-                name: "FileInfo");
+                name: "RulesetInfo");
 
             migrationBuilder.DropTable(
                 name: "BeatmapSetInfo");
 
             migrationBuilder.DropTable(
-                name: "RulesetInfo");
+                name: "FileInfo");
+
+            migrationBuilder.DropTable(
+                name: "BeatmapMetadata");
         }
     }
 }

osu.Game/Migrations/OsuDbContextModelSnapshot.cs

@@ -25,8 +25,6 @@ namespace osu.Game.Migrations
 
                     b.Property<float>("ApproachRate");
 
-                    b.Property<int>("BeatmapInfoID");
-
                     b.Property<float>("CircleSize");
 
                     b.Property<float>("DrainRate");
@@ -39,9 +37,6 @@ namespace osu.Game.Migrations
 
                     b.HasKey("ID");
 
-                    b.HasIndex("BeatmapInfoID")
-                        .IsUnique();
-
                     b.ToTable("BeatmapDifficulty");
                 });
 
@@ -72,6 +67,10 @@ namespace osu.Game.Migrations
 
                     b.Property<string>("MD5Hash");
 
+                    b.Property<int?>("MetadataID");
+
+                    b.Property<int?>("OnlineBeatmapID");
+
                     b.Property<string>("Path");
 
                     b.Property<int>("RulesetID");
@@ -92,12 +91,16 @@ namespace osu.Game.Migrations
 
                     b.HasKey("ID");
 
+                    b.HasIndex("BaseDifficultyID");
+
                     b.HasIndex("BeatmapSetInfoID");
 
                     b.HasIndex("Hash");
 
                     b.HasIndex("MD5Hash");
 
+                    b.HasIndex("MetadataID");
+
                     b.HasIndex("RulesetID");
 
                     b.ToTable("BeatmapInfo");
@@ -119,10 +122,6 @@ namespace osu.Game.Migrations
 
                     b.Property<string>("BackgroundFile");
 
-                    b.Property<int?>("BeatmapInfoID");
-
-                    b.Property<int?>("BeatmapSetInfoID");
-
                     b.Property<int>("PreviewTime");
 
                     b.Property<string>("Source");
@@ -135,12 +134,6 @@ namespace osu.Game.Migrations
 
                     b.HasKey("ID");
 
-                    b.HasIndex("BeatmapInfoID")
-                        .IsUnique();
-
-                    b.HasIndex("BeatmapSetInfoID")
-                        .IsUnique();
-
                     b.ToTable("BeatmapMetadata");
                 });
 
@@ -174,6 +167,8 @@ namespace osu.Game.Migrations
 
                     b.Property<string>("Hash");
 
+                    b.Property<int?>("MetadataID");
+
                     b.Property<int?>("OnlineBeatmapSetID");
 
                     b.Property<bool>("Protected");
@@ -184,6 +179,8 @@ namespace osu.Game.Migrations
 
                     b.HasIndex("Hash");
 
+                    b.HasIndex("MetadataID");
+
                     b.ToTable("BeatmapSetInfo");
                 });
 
@@ -245,49 +242,31 @@ namespace osu.Game.Migrations
 
                     b.HasIndex("Available");
 
-                    b.HasIndex("InstantiationInfo")
-                        .IsUnique();
-
-                    b.HasIndex("Name")
-                        .IsUnique();
-
                     b.ToTable("RulesetInfo");
                 });
 
-            modelBuilder.Entity("osu.Game.Beatmaps.BeatmapDifficulty", b =>
-                {
-                    b.HasOne("osu.Game.Beatmaps.BeatmapInfo")
-                        .WithOne("Difficulty")
-                        .HasForeignKey("osu.Game.Beatmaps.BeatmapDifficulty", "BeatmapInfoID")
-                        .OnDelete(DeleteBehavior.Cascade);
-                });
-
             modelBuilder.Entity("osu.Game.Beatmaps.BeatmapInfo", b =>
                 {
+                    b.HasOne("osu.Game.Beatmaps.BeatmapDifficulty", "BaseDifficulty")
+                        .WithMany()
+                        .HasForeignKey("BaseDifficultyID")
+                        .OnDelete(DeleteBehavior.Cascade);
+
                     b.HasOne("osu.Game.Beatmaps.BeatmapSetInfo", "BeatmapSet")
                         .WithMany("Beatmaps")
                         .HasForeignKey("BeatmapSetInfoID")
                         .OnDelete(DeleteBehavior.Cascade);
 
+                    b.HasOne("osu.Game.Beatmaps.BeatmapMetadata", "Metadata")
+                        .WithMany("Beatmaps")
+                        .HasForeignKey("MetadataID");
+
                     b.HasOne("osu.Game.Rulesets.RulesetInfo", "Ruleset")
                         .WithMany()
                         .HasForeignKey("RulesetID")
                         .OnDelete(DeleteBehavior.Cascade);
                 });
 
-            modelBuilder.Entity("osu.Game.Beatmaps.BeatmapMetadata", b =>
-                {
-                    b.HasOne("osu.Game.Beatmaps.BeatmapInfo", "BeatmapInfo")
-                        .WithOne("Metadata")
-                        .HasForeignKey("osu.Game.Beatmaps.BeatmapMetadata", "BeatmapInfoID")
-                        .OnDelete(DeleteBehavior.Cascade);
-
-                    b.HasOne("osu.Game.Beatmaps.BeatmapSetInfo", "BeatmapSetInfo")
-                        .WithOne("Metadata")
-                        .HasForeignKey("osu.Game.Beatmaps.BeatmapMetadata", "BeatmapSetInfoID")
-                        .OnDelete(DeleteBehavior.Cascade);
-                });
-
             modelBuilder.Entity("osu.Game.Beatmaps.BeatmapSetFileInfo", b =>
                 {
                     b.HasOne("osu.Game.Beatmaps.BeatmapSetInfo")
@@ -300,6 +279,13 @@ namespace osu.Game.Migrations
                         .HasForeignKey("FileInfoID")
                         .OnDelete(DeleteBehavior.Cascade);
                 });
+
+            modelBuilder.Entity("osu.Game.Beatmaps.BeatmapSetInfo", b =>
+                {
+                    b.HasOne("osu.Game.Beatmaps.BeatmapMetadata", "Metadata")
+                        .WithMany("BeatmapSets")
+                        .HasForeignKey("MetadataID");
+                });
 #pragma warning restore 612, 618
         }
     }

osu.Game/Rulesets/UI/RulesetContainer.cs

@@ -172,11 +172,11 @@ namespace osu.Game.Rulesets.UI
 
             // Apply difficulty adjustments from mods before using Difficulty.
             foreach (var mod in Mods.OfType<IApplicableToDifficulty>())
-                mod.ApplyToDifficulty(Beatmap.BeatmapInfo.Difficulty);
+                mod.ApplyToDifficulty(Beatmap.BeatmapInfo.BaseDifficulty);
 
             // Apply defaults
             foreach (var h in Beatmap.HitObjects)
-                h.ApplyDefaults(Beatmap.ControlPointInfo, Beatmap.BeatmapInfo.Difficulty);
+                h.ApplyDefaults(Beatmap.ControlPointInfo, Beatmap.BeatmapInfo.BaseDifficulty);
 
             // Post-process the beatmap
             processor.PostProcess(Beatmap);

osu.Game/Screens/Select/BeatmapDetails.cs

@@ -264,7 +264,7 @@ namespace osu.Game.Screens.Select
             advanced.Beatmap = new BeatmapInfo
             {
                 StarDifficulty = 0,
-                Difficulty = new BeatmapDifficulty
+                BaseDifficulty = new BeatmapDifficulty
                 {
                     CircleSize = 0,
                     DrainRate = 0,

osu.Game/Screens/Select/Details/AdvancedStats.cs

@@ -32,17 +32,17 @@ namespace osu.Game.Screens.Select.Details
                 if ((Beatmap?.Ruleset?.ID ?? 0) == 3)
                 {
                     firstValue.Title = "Key Amount";
-                    firstValue.Value = (int)Math.Round(Beatmap?.Difficulty?.CircleSize ?? 0);
+                    firstValue.Value = (int)Math.Round(Beatmap?.BaseDifficulty?.CircleSize ?? 0);
                 }
                 else
                 {
                     firstValue.Title = "Circle Size";
-                    firstValue.Value = Beatmap?.Difficulty?.CircleSize ?? 0;
+                    firstValue.Value = Beatmap?.BaseDifficulty?.CircleSize ?? 0;
                 }
 
-                hpDrain.Value = beatmap.Difficulty?.DrainRate ?? 0;
+                hpDrain.Value = beatmap.BaseDifficulty?.DrainRate ?? 0;
-                accuracy.Value = beatmap.Difficulty?.OverallDifficulty ?? 0;
+                accuracy.Value = beatmap.BaseDifficulty?.OverallDifficulty ?? 0;
-                approachRate.Value = beatmap.Difficulty?.ApproachRate ?? 0;
+                approachRate.Value = beatmap.BaseDifficulty?.ApproachRate ?? 0;
                 starDifficulty.Value = (float)beatmap.StarDifficulty;
             }
         }

osu.Game/Tests/Visual/TestCaseBeatmapDetails.cs

@@ -29,7 +29,7 @@ namespace osu.Game.Tests.Visual
                     Source = "osu!lazer",
                     Tags = "this beatmap has all the metrics",
                 },
-                Difficulty = new BeatmapDifficulty
+                BaseDifficulty = new BeatmapDifficulty
                 {
                     CircleSize = 7,
                     DrainRate = 1,
@@ -53,7 +53,7 @@ namespace osu.Game.Tests.Visual
                     Source = "osu!lazer",
                     Tags = "this beatmap has ratings metrics but not retries or fails",
                 },
-                Difficulty = new BeatmapDifficulty
+                BaseDifficulty = new BeatmapDifficulty
                 {
                     CircleSize = 6,
                     DrainRate = 9,
@@ -75,7 +75,7 @@ namespace osu.Game.Tests.Visual
                     Source = "osu!lazer",
                     Tags = "this beatmap has retries and fails but no ratings",
                 },
-                Difficulty = new BeatmapDifficulty
+                BaseDifficulty = new BeatmapDifficulty
                 {
                     CircleSize = 3.7f,
                     DrainRate = 6,
@@ -98,7 +98,7 @@ namespace osu.Game.Tests.Visual
                     Source = "osu!lazer",
                     Tags = "this beatmap has no metrics",
                 },
-                Difficulty = new BeatmapDifficulty
+                BaseDifficulty = new BeatmapDifficulty
                 {
                     CircleSize = 5,
                     DrainRate = 5,

osu.Game/Tests/Visual/TestCaseBeatmapSetOverlay.cs

@@ -65,7 +65,7 @@ namespace osu.Game.Tests.Visual
                             StarDifficulty = 1.36,
                             Version = @"BASIC",
                             Ruleset = mania,
-                            Difficulty = new BeatmapDifficulty
+                            BaseDifficulty = new BeatmapDifficulty
                             {
                                 CircleSize = 4,
                                 DrainRate = 6.5f,
@@ -93,7 +93,7 @@ namespace osu.Game.Tests.Visual
                             StarDifficulty = 2.22,
                             Version = @"NOVICE",
                             Ruleset = mania,
-                            Difficulty = new BeatmapDifficulty
+                            BaseDifficulty = new BeatmapDifficulty
                             {
                                 CircleSize = 4,
                                 DrainRate = 7,
@@ -121,7 +121,7 @@ namespace osu.Game.Tests.Visual
                             StarDifficulty = 3.49,
                             Version = @"ADVANCED",
                             Ruleset = mania,
-                            Difficulty = new BeatmapDifficulty
+                            BaseDifficulty = new BeatmapDifficulty
                             {
                                 CircleSize = 4,
                                 DrainRate = 7.5f,
@@ -149,7 +149,7 @@ namespace osu.Game.Tests.Visual
                             StarDifficulty = 4.24,
                             Version = @"EXHAUST",
                             Ruleset = mania,
-                            Difficulty = new BeatmapDifficulty
+                            BaseDifficulty = new BeatmapDifficulty
                             {
                                 CircleSize = 4,
                                 DrainRate = 8,
@@ -177,7 +177,7 @@ namespace osu.Game.Tests.Visual
                             StarDifficulty = 5.26,
                             Version = @"GRAVITY",
                             Ruleset = mania,
-                            Difficulty = new BeatmapDifficulty
+                            BaseDifficulty = new BeatmapDifficulty
                             {
                                 CircleSize = 4,
                                 DrainRate = 8.5f,
@@ -239,7 +239,7 @@ namespace osu.Game.Tests.Visual
                             StarDifficulty = 1.40,
                             Version = @"yzrin's Kantan",
                             Ruleset = taiko,
-                            Difficulty = new BeatmapDifficulty
+                            BaseDifficulty = new BeatmapDifficulty
                             {
                                 CircleSize = 2,
                                 DrainRate = 7,
@@ -267,7 +267,7 @@ namespace osu.Game.Tests.Visual
                             StarDifficulty = 2.23,
                             Version = @"Futsuu",
                             Ruleset = taiko,
-                            Difficulty = new BeatmapDifficulty
+                            BaseDifficulty = new BeatmapDifficulty
                             {
                                 CircleSize = 2,
                                 DrainRate = 6,
@@ -295,7 +295,7 @@ namespace osu.Game.Tests.Visual
                             StarDifficulty = 3.19,
                             Version = @"Muzukashii",
                             Ruleset = taiko,
-                            Difficulty = new BeatmapDifficulty
+                            BaseDifficulty = new BeatmapDifficulty
                             {
                                 CircleSize = 2,
                                 DrainRate = 6,
@@ -323,7 +323,7 @@ namespace osu.Game.Tests.Visual
                             StarDifficulty = 3.97,
                             Version = @"Charlotte's Oni",
                             Ruleset = taiko,
-                            Difficulty = new BeatmapDifficulty
+                            BaseDifficulty = new BeatmapDifficulty
                             {
                                 CircleSize = 5,
                                 DrainRate = 6,
@@ -351,7 +351,7 @@ namespace osu.Game.Tests.Visual
                             StarDifficulty = 5.08,
                             Version = @"Labyrinth Oni",
                             Ruleset = taiko,
-                            Difficulty = new BeatmapDifficulty
+                            BaseDifficulty = new BeatmapDifficulty
                             {
                                 CircleSize = 5,
                                 DrainRate = 5,

osu.Game/Tests/Visual/TestCasePlaySongSelect.cs

@@ -80,7 +80,7 @@ namespace osu.Game.Tests.Visual
                         Ruleset = rulesets.AvailableRulesets.First(),
                         Path = "normal.osu",
                         Version = "Normal",
-                        Difficulty = new BeatmapDifficulty
+                        BaseDifficulty = new BeatmapDifficulty
                         {
                             OverallDifficulty = 3.5f,
                         }
@@ -91,7 +91,7 @@ namespace osu.Game.Tests.Visual
                         Ruleset = rulesets.AvailableRulesets.First(),
                         Path = "hard.osu",
                         Version = "Hard",
-                        Difficulty = new BeatmapDifficulty
+                        BaseDifficulty = new BeatmapDifficulty
                         {
                             OverallDifficulty = 5,
                         }
@@ -102,7 +102,7 @@ namespace osu.Game.Tests.Visual
                         Ruleset = rulesets.AvailableRulesets.First(),
                         Path = "insane.osu",
                         Version = "Insane",
-                        Difficulty = new BeatmapDifficulty
+                        BaseDifficulty = new BeatmapDifficulty
                         {
                             OverallDifficulty = 7,
                         }

osu.Game/Tests/Visual/TestCaseScrollingPlayfield.cs

@@ -48,7 +48,7 @@ namespace osu.Game.Tests.Visual
                 HitObjects = objects,
                 BeatmapInfo = new BeatmapInfo
                 {
-                    Difficulty = new BeatmapDifficulty(),
+                    BaseDifficulty = new BeatmapDifficulty(),
                     Metadata = new BeatmapMetadata()
                 }
             };

osu.Game/osu.Game.csproj

@@ -281,9 +281,9 @@
     <Compile Include="Beatmaps\Drawables\BeatmapSetCover.cs" />
     <Compile Include="Beatmaps\Drawables\BeatmapSetHeader.cs" />
     <Compile Include="Database\DatabaseContextFactory.cs" />
-    <Compile Include="Migrations\20171018125509_InitialCreate.cs" />
+    <Compile Include="Migrations\20171019041408_InitialCreate.cs" />
-    <Compile Include="Migrations\20171018125509_InitialCreate.designer.cs">
+    <Compile Include="Migrations\20171019041408_InitialCreate.designer.cs">
-      <DependentUpon>20171018125509_InitialCreate.cs</DependentUpon>
+      <DependentUpon>20171019041408_InitialCreate.cs</DependentUpon>
     </Compile>
     <Compile Include="Migrations\OsuDbContextModelSnapshot.cs" />
     <Compile Include="Online\API\Requests\GetBeatmapSetRequest.cs" />