calculate similarity at database level

13 files changed, 409 insertions, 255 deletions

diff --git a/MediaBrowser.Api/GamesService.cs b/MediaBrowser.Api/GamesService.cs
index 387771b6d..cb77e62ad 100644
--- a/MediaBrowser.Api/GamesService.cs
+++ b/MediaBrowser.Api/GamesService.cs
@@ -10,6 +10,7 @@ using System.Collections.Generic;
 using System.Globalization;
 using System.IO;
 using System.Linq;
+using MediaBrowser.Model.Querying;
 
 namespace MediaBrowser.Api
 {
@@ -187,18 +188,40 @@ namespace MediaBrowser.Api
         /// <returns>System.Object.</returns>
         public object Get(GetSimilarGames request)
         {
+            var result = GetSimilarItemsResult(request);
+
+            return ToOptimizedSerializedResultUsingCache(result);
+        }
+
+        private QueryResult<BaseItemDto> GetSimilarItemsResult(BaseGetSimilarItemsFromItem request)
+        {
+            var user = !string.IsNullOrWhiteSpace(request.UserId) ? _userManager.GetUserById(request.UserId) : null;
+
+            var item = string.IsNullOrEmpty(request.Id) ?
+                (!string.IsNullOrWhiteSpace(request.UserId) ? user.RootFolder :
+                _libraryManager.RootFolder) : _libraryManager.GetItemById(request.Id);
+
+            var itemsResult = _libraryManager.GetItemList(new InternalItemsQuery(user)
+            {
+                Limit = request.Limit,
+                IncludeItemTypes = new[]
+                {
+                        typeof(Game).Name
+                },
+                SimilarTo = item
+
+            }).ToList();
+
             var dtoOptions = GetDtoOptions(request);
 
-            var result = SimilarItemsHelper.GetSimilarItemsResult(dtoOptions, _userManager,
-                _itemRepo,
-                _libraryManager,
-                _userDataRepository,
-                _dtoService,
-                Logger,
-                request, new[] { typeof(Game) },
-                SimilarItemsHelper.GetSimiliarityScore);
+            var result = new QueryResult<BaseItemDto>
+            {
+                Items = _dtoService.GetBaseItemDtos(itemsResult, dtoOptions, user).ToArray(),
 
-            return ToOptimizedSerializedResultUsingCache(result);
+                TotalRecordCount = itemsResult.Count
+            };
+
+            return result;
         }
     }
 }
diff --git a/MediaBrowser.Api/Movies/MoviesService.cs b/MediaBrowser.Api/Movies/MoviesService.cs
index ce36dd2ac..ff18d440c 100644
--- a/MediaBrowser.Api/Movies/MoviesService.cs
+++ b/MediaBrowser.Api/Movies/MoviesService.cs
@@ -111,18 +111,16 @@ namespace MediaBrowser.Api.Movies
         /// </summary>
         /// <param name="request">The request.</param>
         /// <returns>System.Object.</returns>
-        public async Task<object> Get(GetSimilarMovies request)
+        public object Get(GetSimilarMovies request)
         {
-            var result = await GetSimilarItemsResult(
-                request, SimilarItemsHelper.GetSimiliarityScore).ConfigureAwait(false);
+            var result = GetSimilarItemsResult(request);
 
             return ToOptimizedSerializedResultUsingCache(result);
         }
 
-        public async Task<object> Get(GetSimilarTrailers request)
+        public object Get(GetSimilarTrailers request)
         {
-            var result = await GetSimilarItemsResult(
-                request, SimilarItemsHelper.GetSimiliarityScore).ConfigureAwait(false);
+            var result = GetSimilarItemsResult(request);
 
             return ToOptimizedSerializedResultUsingCache(result);
         }
@@ -131,42 +129,16 @@ namespace MediaBrowser.Api.Movies
         {
             var user = _userManager.GetUserById(request.UserId);
 
-            var query = new InternalItemsQuery(user)
-            {
-                IncludeItemTypes = new[]
-                {
-                    typeof(Movie).Name,
-                    typeof(Trailer).Name,
-                    //typeof(LiveTvProgram).Name
-                },
-                // IsMovie = true
-            };
-
-            var parentIds = string.IsNullOrWhiteSpace(request.ParentId) ? new string[] { } : new[] { request.ParentId };
-            var movies = _libraryManager.GetItemList(query, parentIds)
-                .OrderBy(i => (int)i.SourceType);
-
-            var listEligibleForSuggestion = new List<BaseItem>();
-
-            var list = movies.ToList();
-
-            listEligibleForSuggestion.AddRange(list);
-
-            listEligibleForSuggestion = listEligibleForSuggestion
-                .DistinctBy(i => i.Name, StringComparer.OrdinalIgnoreCase)
-                .DistinctBy(i => i.GetProviderId(MetadataProviders.Imdb) ?? Guid.NewGuid().ToString(), StringComparer.OrdinalIgnoreCase)
-                .ToList();
-
             var dtoOptions = GetDtoOptions(request);
 
             dtoOptions.Fields = request.GetItemFields().ToList();
 
-            var result = GetRecommendationCategories(user, request.ParentId, listEligibleForSuggestion, request.CategoryLimit, request.ItemLimit, dtoOptions);
+            var result = GetRecommendationCategories(user, request.ParentId, request.CategoryLimit, request.ItemLimit, dtoOptions);
 
             return ToOptimizedResult(result);
         }
 
-        private async Task<ItemsResult> GetSimilarItemsResult(BaseGetSimilarItemsFromItem request, Func<BaseItem, List<PersonInfo>, List<PersonInfo>, BaseItem, int> getSimilarityScore)
+        private QueryResult<BaseItemDto> GetSimilarItemsResult(BaseGetSimilarItemsFromItem request)
         {
             var user = !string.IsNullOrWhiteSpace(request.UserId) ? _userManager.GetUserById(request.UserId) : null;
 
@@ -174,57 +146,32 @@ namespace MediaBrowser.Api.Movies
                 (!string.IsNullOrWhiteSpace(request.UserId) ? user.RootFolder :
                 _libraryManager.RootFolder) : _libraryManager.GetItemById(request.Id);
 
-            var query = new InternalItemsQuery(user)
+            var itemsResult = _libraryManager.GetItemList(new InternalItemsQuery(user)
             {
+                Limit = request.Limit,
                 IncludeItemTypes = new[]
                 {
-                    typeof(Movie).Name,
-                    typeof(Trailer).Name,
-                    //typeof(LiveTvProgram).Name
+                        typeof(Movie).Name,
+                        typeof(Trailer).Name,
+                        typeof(LiveTvProgram).Name
                 },
-                //IsMovie = true
-            };
-
-            var list = _libraryManager.GetItemList(query)
-                .OrderBy(i => (int)i.SourceType)
-                .DistinctBy(i => i.GetProviderId(MetadataProviders.Imdb) ?? Guid.NewGuid().ToString("N"))
-                .ToList();
-
-            if (item is Video)
-            {
-                var imdbId = item.GetProviderId(MetadataProviders.Imdb);
-
-                // Use imdb id to try to filter duplicates of the same item
-                if (!string.IsNullOrWhiteSpace(imdbId))
-                {
-                    list = list
-                        .Where(i => !string.Equals(imdbId, i.GetProviderId(MetadataProviders.Imdb), StringComparison.OrdinalIgnoreCase))
-                        .ToList();
-                }
-            }
-
-            var items = SimilarItemsHelper.GetSimilaritems(item, _libraryManager, list, getSimilarityScore).ToList();
-
-            IEnumerable<BaseItem> returnItems = items;
-
-            if (request.Limit.HasValue)
-            {
-                returnItems = returnItems.Take(request.Limit.Value);
-            }
+                IsMovie = true,
+                SimilarTo = item
+            }).ToList();
 
             var dtoOptions = GetDtoOptions(request);
 
-            var result = new ItemsResult
+            var result = new QueryResult<BaseItemDto>
             {
-                Items = _dtoService.GetBaseItemDtos(returnItems, dtoOptions, user).ToArray(),
+                Items = _dtoService.GetBaseItemDtos(itemsResult, dtoOptions, user).ToArray(),
 
-                TotalRecordCount = items.Count
+                TotalRecordCount = itemsResult.Count
             };
 
             return result;
         }
 
-        private IEnumerable<RecommendationDto> GetRecommendationCategories(User user, string parentId, List<BaseItem> allMovies, int categoryLimit, int itemLimit, DtoOptions dtoOptions)
+        private IEnumerable<RecommendationDto> GetRecommendationCategories(User user, string parentId, int categoryLimit, int itemLimit, DtoOptions dtoOptions)
         {
             var categories = new List<RecommendationDto>();
 
@@ -260,7 +207,7 @@ namespace MediaBrowser.Api.Movies
                 IsFavoriteOrLiked = true,
                 ExcludeItemIds = recentlyPlayedMovies.Select(i => i.Id.ToString("N")).ToArray()
 
-            }, parentIds);
+            }, parentIds).ToList();
 
             var mostRecentMovies = recentlyPlayedMovies.Take(6).ToList();
             // Get recently played directors
@@ -273,8 +220,8 @@ namespace MediaBrowser.Api.Movies
                 .OrderBy(i => Guid.NewGuid())
                 .ToList();
 
-            var similarToRecentlyPlayed = GetSimilarTo(user, allMovies, recentlyPlayedMovies.Take(7).OrderBy(i => Guid.NewGuid()), itemLimit, dtoOptions, RecommendationType.SimilarToRecentlyPlayed).GetEnumerator();
-            var similarToLiked = GetSimilarTo(user, allMovies, likedMovies, itemLimit, dtoOptions, RecommendationType.SimilarToLikedItem).GetEnumerator();
+            var similarToRecentlyPlayed = GetSimilarTo(user, recentlyPlayedMovies, itemLimit, dtoOptions, RecommendationType.SimilarToRecentlyPlayed).GetEnumerator();
+            var similarToLiked = GetSimilarTo(user, likedMovies, itemLimit, dtoOptions, RecommendationType.SimilarToLikedItem).GetEnumerator();
 
             var hasDirectorFromRecentlyPlayed = GetWithDirector(user, recentDirectors, itemLimit, dtoOptions, RecommendationType.HasDirectorFromRecentlyPlayed).GetEnumerator();
             var hasActorFromRecentlyPlayed = GetWithActor(user, recentActors, itemLimit, dtoOptions, RecommendationType.HasActorFromRecentlyPlayed).GetEnumerator();
@@ -389,14 +336,23 @@ namespace MediaBrowser.Api.Movies
             }
         }
 
-        private IEnumerable<RecommendationDto> GetSimilarTo(User user, List<BaseItem> allMovies, IEnumerable<BaseItem> baselineItems, int itemLimit, DtoOptions dtoOptions, RecommendationType type)
+        private IEnumerable<RecommendationDto> GetSimilarTo(User user, List<BaseItem> baselineItems, int itemLimit, DtoOptions dtoOptions, RecommendationType type)
         {
             foreach (var item in baselineItems)
             {
-                var similar = SimilarItemsHelper
-                    .GetSimilaritems(item, _libraryManager, allMovies, SimilarItemsHelper.GetSimiliarityScore)
-                    .Take(itemLimit)
-                    .ToList();
+                var similar = _libraryManager.GetItemList(new InternalItemsQuery(user)
+                {
+                    Limit = itemLimit,
+                    IncludeItemTypes = new[]
+                    {
+                        typeof(Movie).Name,
+                        typeof(Trailer).Name,
+                        typeof(LiveTvProgram).Name
+                    },
+                    IsMovie = true,
+                    SimilarTo = item
+
+                }).ToList();
 
                 if (similar.Count > 0)
                 {
diff --git a/MediaBrowser.Api/TvShowsService.cs b/MediaBrowser.Api/TvShowsService.cs
index aa0485d57..5ccfede1e 100644
--- a/MediaBrowser.Api/TvShowsService.cs
+++ b/MediaBrowser.Api/TvShowsService.cs
@@ -12,6 +12,7 @@ using ServiceStack;
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using MediaBrowser.Model.Dto;
 
 namespace MediaBrowser.Api
 {
@@ -273,18 +274,40 @@ namespace MediaBrowser.Api
         /// <returns>System.Object.</returns>
         public object Get(GetSimilarShows request)
         {
+            var result = GetSimilarItemsResult(request);
+
+            return ToOptimizedSerializedResultUsingCache(result);
+        }
+
+        private QueryResult<BaseItemDto> GetSimilarItemsResult(BaseGetSimilarItemsFromItem request)
+        {
+            var user = !string.IsNullOrWhiteSpace(request.UserId) ? _userManager.GetUserById(request.UserId) : null;
+
+            var item = string.IsNullOrEmpty(request.Id) ?
+                (!string.IsNullOrWhiteSpace(request.UserId) ? user.RootFolder :
+                _libraryManager.RootFolder) : _libraryManager.GetItemById(request.Id);
+
+            var itemsResult = _libraryManager.GetItemList(new InternalItemsQuery(user)
+            {
+                Limit = request.Limit,
+                IncludeItemTypes = new[]
+                {
+                        typeof(Series).Name
+                },
+                SimilarTo = item
+
+            }).ToList();
+
             var dtoOptions = GetDtoOptions(request);
 
-            var result = SimilarItemsHelper.GetSimilarItemsResult(dtoOptions, _userManager,
-                _itemRepo,
-                _libraryManager,
-                _userDataManager,
-                _dtoService,
-                Logger,
-                request, new[] { typeof(Series) },
-                SimilarItemsHelper.GetSimiliarityScore);
+            var result = new QueryResult<BaseItemDto>
+            {
+                Items = _dtoService.GetBaseItemDtos(itemsResult, dtoOptions, user).ToArray(),
 
-            return ToOptimizedSerializedResultUsingCache(result);
+                TotalRecordCount = itemsResult.Count
+            };
+
+            return result;
         }
 
         public object Get(GetUpcomingEpisodes request)
diff --git a/MediaBrowser.Controller/Entities/InternalItemsQuery.cs b/MediaBrowser.Controller/Entities/InternalItemsQuery.cs
index f3f05a08f..0047a13b2 100644
--- a/MediaBrowser.Controller/Entities/InternalItemsQuery.cs
+++ b/MediaBrowser.Controller/Entities/InternalItemsQuery.cs
@@ -19,6 +19,8 @@ namespace MediaBrowser.Controller.Entities
 
         public User User { get; set; }
 
+        public BaseItem SimilarTo { get; set; }
+
         public bool? IsFolder { get; set; }
         public bool? IsFavorite { get; set; }
         public bool? IsFavoriteOrLiked { get; set; }
diff --git a/MediaBrowser.Server.Implementations/Persistence/IDbConnector.cs b/MediaBrowser.Server.Implementations/Persistence/IDbConnector.cs
index cac9fe983..985d79a0a 100644
--- a/MediaBrowser.Server.Implementations/Persistence/IDbConnector.cs
+++ b/MediaBrowser.Server.Implementations/Persistence/IDbConnector.cs
@@ -6,5 +6,6 @@ namespace MediaBrowser.Server.Implementations.Persistence
     public interface IDbConnector
     {
         Task<IDbConnection> Connect(string dbPath);
+        void BindSimilarityScoreFunction(IDbConnection connection);
     }
 }
diff --git a/MediaBrowser.Server.Implementations/Persistence/SqliteExtensions.cs b/MediaBrowser.Server.Implementations/Persistence/SqliteExtensions.cs
new file mode 100644
index 000000000..5e07bac31
--- /dev/null
+++ b/MediaBrowser.Server.Implementations/Persistence/SqliteExtensions.cs
@@ -0,0 +1,175 @@
+using System;
+using System.Collections.Generic;
+using System.Data;
+using System.Data.SQLite;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using MediaBrowser.Model.Logging;
+
+namespace MediaBrowser.Server.Implementations.Persistence
+{
+    /// <summary>
+    /// Class SQLiteExtensions
+    /// </summary>
+    public static class SqliteExtensions
+    {
+        /// <summary>
+        /// Connects to db.
+        /// </summary>
+        /// <param name="dbPath">The db path.</param>
+        /// <param name="logger">The logger.</param>
+        /// <returns>Task{IDbConnection}.</returns>
+        /// <exception cref="System.ArgumentNullException">dbPath</exception>
+        public static async Task<IDbConnection> ConnectToDb(string dbPath, ILogger logger)
+        {
+            if (string.IsNullOrEmpty(dbPath))
+            {
+                throw new ArgumentNullException("dbPath");
+            }
+
+            logger.Info("Sqlite {0} opening {1}", SQLiteConnection.SQLiteVersion, dbPath);
+
+            var connectionstr = new SQLiteConnectionStringBuilder
+            {
+                PageSize = 4096,
+                CacheSize = 2000,
+                SyncMode = SynchronizationModes.Normal,
+                DataSource = dbPath,
+                JournalMode = SQLiteJournalModeEnum.Wal
+            };
+
+            var connection = new SQLiteConnection(connectionstr.ConnectionString);
+
+            await connection.OpenAsync().ConfigureAwait(false);
+
+            return connection;
+        }
+
+        public static void BindGetSimilarityScore(IDbConnection connection, ILogger logger)
+        {
+            var sqlConnection = (SQLiteConnection) connection;
+            SimiliarToFunction.Logger = logger;
+            sqlConnection.BindFunction(new SimiliarToFunction());
+        }
+
+        public static void BindFunction(this SQLiteConnection connection, SQLiteFunction function)
+        {
+            var attributes = function.GetType().GetCustomAttributes(typeof(SQLiteFunctionAttribute), true).Cast<SQLiteFunctionAttribute>().ToArray();
+            if (attributes.Length == 0)
+            {
+                throw new InvalidOperationException("SQLiteFunction doesn't have SQLiteFunctionAttribute");
+            }
+            connection.BindFunction(attributes[0], function);
+        }
+    }
+
+    [SQLiteFunction(Name = "GetSimilarityScore", Arguments = 12, FuncType = FunctionType.Scalar)]
+    public class SimiliarToFunction : SQLiteFunction
+    {
+        internal static ILogger Logger;
+
+        public override object Invoke(object[] args)
+        {
+            var score = 0;
+
+            var inputOfficialRating = args[0] as string;
+            var rowOfficialRating = args[1] as string;
+            if (!string.IsNullOrWhiteSpace(inputOfficialRating) && string.Equals(inputOfficialRating, rowOfficialRating))
+            {
+                score += 10;
+            }
+
+            long? inputYear = args[2] == null ? (long?)null : (long)args[2];
+            long? rowYear = args[3] == null ? (long?)null : (long)args[3];
+
+            if (inputYear.HasValue && rowYear.HasValue)
+            {
+                var diff = Math.Abs(inputYear.Value - rowYear.Value);
+
+                // Add if they came out within the same decade
+                if (diff < 10)
+                {
+                    score += 2;
+                }
+
+                // And more if within five years
+                if (diff < 5)
+                {
+                    score += 2;
+                }
+            }
+
+            // genres
+            score += GetListScore(args, 4, 5);
+
+            // tags
+            score += GetListScore(args, 6, 7);
+
+            // keywords
+            score += GetListScore(args, 8, 9);
+
+            // studios
+            score += GetListScore(args, 10, 11, 3);
+
+
+            // TODO: People
+    //        var item2PeopleNames = allPeople.Where(i => i.ItemId == item2.Id)
+    //.Select(i => i.Name)
+    //.Where(i => !string.IsNullOrWhiteSpace(i))
+    //.DistinctNames()
+    //.ToDictionary(i => i, StringComparer.OrdinalIgnoreCase);
+
+    //        points += item1People.Where(i => item2PeopleNames.ContainsKey(i.Name)).Sum(i =>
+    //        {
+    //            if (string.Equals(i.Type, PersonType.Director, StringComparison.OrdinalIgnoreCase) || string.Equals(i.Role, PersonType.Director, StringComparison.OrdinalIgnoreCase))
+    //            {
+    //                return 5;
+    //            }
+    //            if (string.Equals(i.Type, PersonType.Actor, StringComparison.OrdinalIgnoreCase) || string.Equals(i.Role, PersonType.Actor, StringComparison.OrdinalIgnoreCase))
+    //            {
+    //                return 3;
+    //            }
+    //            if (string.Equals(i.Type, PersonType.Composer, StringComparison.OrdinalIgnoreCase) || string.Equals(i.Role, PersonType.Composer, StringComparison.OrdinalIgnoreCase))
+    //            {
+    //                return 3;
+    //            }
+    //            if (string.Equals(i.Type, PersonType.GuestStar, StringComparison.OrdinalIgnoreCase) || string.Equals(i.Role, PersonType.GuestStar, StringComparison.OrdinalIgnoreCase))
+    //            {
+    //                return 3;
+    //            }
+    //            if (string.Equals(i.Type, PersonType.Writer, StringComparison.OrdinalIgnoreCase) || string.Equals(i.Role, PersonType.Writer, StringComparison.OrdinalIgnoreCase))
+    //            {
+    //                return 2;
+    //            }
+
+    //            return 1;
+    //        });
+
+    //        return points;
+
+            //Logger.Debug("Returning score {0}", score);
+            return score;
+        }
+
+        private int GetListScore(object[] args, int index1, int index2, int value = 10)
+        {
+            var score = 0;
+
+            var inputGenres = args[index1] as string;
+            var rowGenres = args[index2] as string;
+            var inputGenreList = string.IsNullOrWhiteSpace(inputGenres) ? new string[] { } : inputGenres.Split(new[] { '|' }, StringSplitOptions.RemoveEmptyEntries);
+            var rowGenresList = string.IsNullOrWhiteSpace(rowGenres) ? new string[] { } : rowGenres.Split(new[] { '|' }, StringSplitOptions.RemoveEmptyEntries);
+
+            foreach (var genre in inputGenreList)
+            {
+                if (rowGenresList.Contains(genre, StringComparer.OrdinalIgnoreCase))
+                {
+                    score += value;
+                }
+            }
+
+            return score;
+        }
+    }
+}
diff --git a/MediaBrowser.Server.Implementations/Persistence/SqliteItemRepository.cs b/MediaBrowser.Server.Implementations/Persistence/SqliteItemRepository.cs
index 3149352a9..131158dd2 100644
--- a/MediaBrowser.Server.Implementations/Persistence/SqliteItemRepository.cs
+++ b/MediaBrowser.Server.Implementations/Persistence/SqliteItemRepository.cs
@@ -15,6 +15,7 @@ using System.Globalization;
 using System.IO;
 using System.Linq;
 using System.Runtime.Serialization;
+using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 using MediaBrowser.Common.Extensions;
@@ -258,6 +259,8 @@ namespace MediaBrowser.Server.Implementations.Persistence
             new MediaStreamColumns(_connection, Logger).AddColumns();
 
             DataExtensions.Attach(_connection, Path.Combine(_config.ApplicationPaths.DataPath, "userdata_v2.db"), "UserDataDb");
+
+            dbConnector.BindSimilarityScoreFunction(_connection);
         }
 
         private readonly string[] _retriveItemColumns =
@@ -1575,7 +1578,7 @@ namespace MediaBrowser.Server.Implementations.Persistence
             return false;
         }
 
-        private string[] GetFinalColumnsToSelect(InternalItemsQuery query, string[] startColumns)
+        private string[] GetFinalColumnsToSelect(InternalItemsQuery query, string[] startColumns, IDbCommand cmd)
         {
             var list = startColumns.ToList();
 
@@ -1590,6 +1593,45 @@ namespace MediaBrowser.Server.Implementations.Persistence
                 list.Add("UserDataDb.UserData.rating");
             }
 
+            if (query.SimilarTo != null)
+            {
+                var item = query.SimilarTo;
+
+                var builder = new StringBuilder();
+                builder.Append("GetSimilarityScore(");
+
+                builder.Append("@ItemOfficialRating,");
+                builder.Append("OfficialRating,");
+
+                builder.Append("@ItemProductionYear,");
+                builder.Append("ProductionYear,");
+
+                builder.Append("@ItemGenres,");
+                builder.Append("Genres,");
+
+                builder.Append("@ItemTags,");
+                builder.Append("Tags,");
+
+                builder.Append("@ItemKeywords,");
+                builder.Append("(select group_concat((Select Value from ItemValues where ItemId=Guid and Type=5), '|')),");
+
+                builder.Append("@ItemStudios,");
+                builder.Append("Studios");
+                builder.Append(") as SimilarityScore");
+
+                list.Add(builder.ToString());
+                cmd.Parameters.Add(cmd, "@ItemOfficialRating", DbType.String).Value = item.OfficialRating;
+                cmd.Parameters.Add(cmd, "@ItemProductionYear", DbType.Int32).Value = item.ProductionYear ?? -1;
+                cmd.Parameters.Add(cmd, "@ItemGenres", DbType.String).Value = string.Join("|", item.Genres.ToArray());
+                cmd.Parameters.Add(cmd, "@ItemTags", DbType.String).Value = string.Join("|", item.Tags.ToArray());
+                cmd.Parameters.Add(cmd, "@ItemKeywords", DbType.String).Value = string.Join("|", item.Keywords.ToArray());
+                cmd.Parameters.Add(cmd, "@ItemStudios", DbType.String).Value = string.Join("|", item.Studios.ToArray());
+
+                var excludeIds = query.ExcludeItemIds.ToList();
+                excludeIds.Add(item.Id.ToString("N"));
+                query.ExcludeItemIds = excludeIds.ToArray();
+            }
+
             return list.ToArray();
         }
 
@@ -1616,7 +1658,7 @@ namespace MediaBrowser.Server.Implementations.Persistence
 
             using (var cmd = _connection.CreateCommand())
             {
-                cmd.CommandText = "select " + string.Join(",", GetFinalColumnsToSelect(query, _retriveItemColumns)) + " from TypedBaseItems";
+                cmd.CommandText = "select " + string.Join(",", GetFinalColumnsToSelect(query, _retriveItemColumns, cmd)) + " from TypedBaseItems";
                 cmd.CommandText += GetJoinUserDataText(query);
 
                 if (EnableJoinUserData(query))
@@ -1706,7 +1748,7 @@ namespace MediaBrowser.Server.Implementations.Persistence
 
             using (var cmd = _connection.CreateCommand())
             {
-                cmd.CommandText = "select " + string.Join(",", GetFinalColumnsToSelect(query, _retriveItemColumns)) + " from TypedBaseItems";
+                cmd.CommandText = "select " + string.Join(",", GetFinalColumnsToSelect(query, _retriveItemColumns, cmd)) + " from TypedBaseItems";
                 cmd.CommandText += GetJoinUserDataText(query);
 
                 if (EnableJoinUserData(query))
@@ -1789,6 +1831,15 @@ namespace MediaBrowser.Server.Implementations.Persistence
 
         private string GetOrderByText(InternalItemsQuery query)
         {
+            if (query.SimilarTo != null)
+            {
+                if (query.SortBy == null || query.SortBy.Length == 0)
+                {
+                    query.SortBy = new[] { "SimilarityScore", "Random" };
+                    query.SortOrder = SortOrder.Descending;
+                }
+            }
+
             if (query.SortBy == null || query.SortBy.Length == 0)
             {
                 return string.Empty;
@@ -1879,7 +1930,7 @@ namespace MediaBrowser.Server.Implementations.Persistence
 
             using (var cmd = _connection.CreateCommand())
             {
-                cmd.CommandText = "select " + string.Join(",", GetFinalColumnsToSelect(query, new[] { "guid" })) + " from TypedBaseItems";
+                cmd.CommandText = "select " + string.Join(",", GetFinalColumnsToSelect(query, new[] { "guid" }, cmd)) + " from TypedBaseItems";
                 cmd.CommandText += GetJoinUserDataText(query);
 
                 if (EnableJoinUserData(query))
@@ -2022,7 +2073,7 @@ namespace MediaBrowser.Server.Implementations.Persistence
 
             using (var cmd = _connection.CreateCommand())
             {
-                cmd.CommandText = "select " + string.Join(",", GetFinalColumnsToSelect(query, new[] { "guid" })) + " from TypedBaseItems";
+                cmd.CommandText = "select " + string.Join(",", GetFinalColumnsToSelect(query, new[] { "guid" }, cmd)) + " from TypedBaseItems";
 
                 var whereClauses = GetWhereClauses(query, cmd);
                 cmd.CommandText += GetJoinUserDataText(query);
@@ -2148,24 +2199,7 @@ namespace MediaBrowser.Server.Implementations.Persistence
                 }
                 else
                 {
-                    if (query.IsMovie.Value)
-                    {
-                        var typeClauses = new List<string>();
-                        var typeIndex = 0;
-                        foreach (var type in alternateTypes)
-                        {
-                            var paramName = "@AlternateType" + typeIndex.ToString(CultureInfo.InvariantCulture);
-                            typeClauses.Add("Type=" + paramName);
-                            cmd.Parameters.Add(cmd, paramName, DbType.String).Value = type;
-                            typeIndex++;
-                        }
-
-                        whereClauses.Add("(IsMovie=@IsMovie OR " + string.Join(" OR ", typeClauses.ToArray()) + ")");
-                    }
-                    else
-                    {
-                        whereClauses.Add("(IsMovie is null OR IsMovie=@IsMovie)");
-                    }
+                    whereClauses.Add("(IsMovie is null OR IsMovie=@IsMovie)");
                 }
                 cmd.Parameters.Add(cmd, "@IsMovie", DbType.Boolean).Value = query.IsMovie;
             }
diff --git a/MediaBrowser.Server.Mono/MediaBrowser.Server.Mono.csproj b/MediaBrowser.Server.Mono/MediaBrowser.Server.Mono.csproj
index b71877e17..45071c9d9 100644
--- a/MediaBrowser.Server.Mono/MediaBrowser.Server.Mono.csproj
+++ b/MediaBrowser.Server.Mono/MediaBrowser.Server.Mono.csproj
@@ -82,11 +82,14 @@
     </Reference>
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="..\MediaBrowser.Server.Implementations\Persistence\SqliteExtensions.cs">
+      <Link>Native\SqliteExtensions.cs</Link>
+    </Compile>
     <Compile Include="..\SharedVersion.cs">
       <Link>Properties\SharedVersion.cs</Link>
     </Compile>
     <Compile Include="Native\BaseMonoApp.cs" />
-    <Compile Include="Native\SqliteExtensions.cs" />
+    <Compile Include="Native\DbConnector.cs" />
     <Compile Include="Networking\CertificateGenerator.cs" />
     <Compile Include="Program.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
diff --git a/MediaBrowser.Server.Mono/Native/DbConnector.cs b/MediaBrowser.Server.Mono/Native/DbConnector.cs
new file mode 100644
index 000000000..536cd7322
--- /dev/null
+++ b/MediaBrowser.Server.Mono/Native/DbConnector.cs
@@ -0,0 +1,29 @@
+using System;
+using System.Data;
+using System.Data.SQLite;
+using System.Threading.Tasks;
+using MediaBrowser.Model.Logging;
+using MediaBrowser.Server.Implementations.Persistence;
+
+namespace MediaBrowser.Server.Mono.Native
+{
+    public class DbConnector : IDbConnector
+    {
+        private readonly ILogger _logger;
+
+        public DbConnector(ILogger logger)
+        {
+            _logger = logger;
+        }
+
+        public void BindSimilarityScoreFunction(IDbConnection connection)
+        {
+            SqliteExtensions.BindGetSimilarityScore(connection, _logger);
+        }
+
+        public Task<IDbConnection> Connect(string dbPath)
+        {
+            return SqliteExtensions.ConnectToDb(dbPath, _logger);
+        }
+    }
+}
\ No newline at end of file
diff --git a/MediaBrowser.Server.Mono/Native/SqliteExtensions.cs b/MediaBrowser.Server.Mono/Native/SqliteExtensions.cs
deleted file mode 100644
index ca2327282..000000000
--- a/MediaBrowser.Server.Mono/Native/SqliteExtensions.cs
+++ /dev/null
@@ -1,62 +0,0 @@
-using System;
-using System.Data;
-using System.Data.SQLite;
-using System.Threading.Tasks;
-using MediaBrowser.Model.Logging;
-using MediaBrowser.Server.Implementations.Persistence;
-
-namespace MediaBrowser.Server.Mono.Native
-{
-    /// <summary>
-    /// Class SQLiteExtensions
-    /// </summary>
-    static class SqliteExtensions
-    {
-        /// <summary>
-        /// Connects to db.
-        /// </summary>
-        /// <param name="dbPath">The db path.</param>
-        /// <param name="logger">The logger.</param>
-        /// <returns>Task{IDbConnection}.</returns>
-        /// <exception cref="System.ArgumentNullException">dbPath</exception>
-        public static async Task<IDbConnection> ConnectToDb(string dbPath, ILogger logger)
-        {
-            if (string.IsNullOrEmpty(dbPath))
-            {
-                throw new ArgumentNullException("dbPath");
-            }
-
-            logger.Info("Sqlite {0} opening {1}", SQLiteConnection.SQLiteVersion, dbPath);
-
-            var connectionstr = new SQLiteConnectionStringBuilder
-            {
-                PageSize = 4096,
-                CacheSize = 2000,
-                SyncMode = SynchronizationModes.Normal,
-                DataSource = dbPath,
-                JournalMode = SQLiteJournalModeEnum.Wal
-            };
-
-            var connection = new SQLiteConnection(connectionstr.ConnectionString);
-
-            await connection.OpenAsync().ConfigureAwait(false);
-
-            return connection;
-        }
-    }
-
-    public class DbConnector : IDbConnector
-    {
-        private readonly ILogger _logger;
-
-        public DbConnector(ILogger logger)
-        {
-            _logger = logger;
-        }
-
-        public Task<IDbConnection> Connect(string dbPath)
-        {
-            return SqliteExtensions.ConnectToDb(dbPath, _logger);
-        }
-    }
-}
\ No newline at end of file
diff --git a/MediaBrowser.ServerApplication/MediaBrowser.ServerApplication.csproj b/MediaBrowser.ServerApplication/MediaBrowser.ServerApplication.csproj
index 366d4b608..35660b2b1 100644
--- a/MediaBrowser.ServerApplication/MediaBrowser.ServerApplication.csproj
+++ b/MediaBrowser.ServerApplication/MediaBrowser.ServerApplication.csproj
@@ -97,6 +97,9 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="..\MediaBrowser.Server.Implementations\Persistence\SqliteExtensions.cs">
+      <Link>Native\SqliteExtensions.cs</Link>
+    </Compile>
     <Compile Include="..\SharedVersion.cs">
       <Link>Properties\SharedVersion.cs</Link>
     </Compile>
@@ -114,7 +117,7 @@
     </Compile>
     <Compile Include="MainStartup.cs" />
     <Compile Include="Native\LnkShortcutHandler.cs" />
-    <Compile Include="Native\SqliteExtensions.cs" />
+    <Compile Include="Native\DbConnector.cs" />
     <Compile Include="Native\Standby.cs" />
     <Compile Include="Native\ServerAuthorization.cs" />
     <Compile Include="Native\WindowsApp.cs" />
diff --git a/MediaBrowser.ServerApplication/Native/DbConnector.cs b/MediaBrowser.ServerApplication/Native/DbConnector.cs
new file mode 100644
index 000000000..f93cad62c
--- /dev/null
+++ b/MediaBrowser.ServerApplication/Native/DbConnector.cs
@@ -0,0 +1,38 @@
+using System;
+using System.Data;
+using System.Data.SQLite;
+using System.Threading.Tasks;
+using MediaBrowser.Model.Logging;
+using MediaBrowser.Server.Implementations.Persistence;
+
+namespace MediaBrowser.ServerApplication.Native
+{
+    public class DbConnector : IDbConnector
+    {
+        private readonly ILogger _logger;
+
+        public DbConnector(ILogger logger)
+        {
+            _logger = logger;
+        }
+
+        public void BindSimilarityScoreFunction(IDbConnection connection)
+        {
+            SqliteExtensions.BindGetSimilarityScore(connection, _logger);
+        }
+
+        public async Task<IDbConnection> Connect(string dbPath)
+        {
+            try
+            {
+                return await SqliteExtensions.ConnectToDb(dbPath, _logger).ConfigureAwait(false);
+            }
+            catch (Exception ex)
+            {
+                _logger.ErrorException("Error opening database {0}", ex, dbPath);
+
+                throw;
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/MediaBrowser.ServerApplication/Native/SqliteExtensions.cs b/MediaBrowser.ServerApplication/Native/SqliteExtensions.cs
deleted file mode 100644
index bdf5c3323..000000000
--- a/MediaBrowser.ServerApplication/Native/SqliteExtensions.cs
+++ /dev/null
@@ -1,71 +0,0 @@
-using System;
-using System.Data;
-using System.Data.SQLite;
-using System.Threading.Tasks;
-using MediaBrowser.Model.Logging;
-using MediaBrowser.Server.Implementations.Persistence;
-
-namespace MediaBrowser.ServerApplication.Native
-{
-    /// <summary>
-    /// Class SQLiteExtensions
-    /// </summary>
-    static class SqliteExtensions
-    {
-        /// <summary>
-        /// Connects to db.
-        /// </summary>
-        /// <param name="dbPath">The db path.</param>
-        /// <param name="logger">The logger.</param>
-        /// <returns>Task{IDbConnection}.</returns>
-        /// <exception cref="System.ArgumentNullException">dbPath</exception>
-        public static async Task<IDbConnection> ConnectToDb(string dbPath, ILogger logger)
-        {
-            if (string.IsNullOrEmpty(dbPath))
-            {
-                throw new ArgumentNullException("dbPath");
-            }
-
-            logger.Info("Sqlite {0} opening {1}", SQLiteConnection.SQLiteVersion, dbPath);
-
-            var connectionstr = new SQLiteConnectionStringBuilder
-            {
-                PageSize = 4096,
-                CacheSize = 2000,
-                SyncMode = SynchronizationModes.Normal,
-                DataSource = dbPath,
-                JournalMode = SQLiteJournalModeEnum.Wal
-            };
-
-            var connection = new SQLiteConnection(connectionstr.ConnectionString);
-
-            await connection.OpenAsync().ConfigureAwait(false);
-
-            return connection;
-        }
-    }
-
-    public class DbConnector : IDbConnector
-    {
-        private readonly ILogger _logger;
-
-        public DbConnector(ILogger logger)
-        {
-            _logger = logger;
-        }
-
-        public async Task<IDbConnection> Connect(string dbPath)
-        {
-            try
-            {
-                return await SqliteExtensions.ConnectToDb(dbPath, _logger).ConfigureAwait(false);
-            }
-            catch (Exception ex)
-            {
-                _logger.ErrorException("Error opening database {0}", ex, dbPath);
-
-                throw;
-            }
-        }
-    }
-}
\ No newline at end of file