c# - Merge complex entity graph with database -

in code first data model i'm retrieving info id3 tags , putting database. have following table relations:

master entity track. fields: artists, composers, performers many many relationship , conductor many one. of type artist.

ids of entities generated hashing various properties on creation of object:

• in track it's path,
• in album it's name combined names of contained artists , index field (it's because there may duplicate album names define album uniquely need include artists; index field represents possible multiple discs per album),
• in picture it's data,
• the remaining entities ids field name.

code creating track (with taglib-sharp):

public track(string path)     {         path = path;          using (var f = new audiofile(path))         {             beatsperminute = f.tag.beatsperminute != 0 ? (int?)f.tag.beatsperminute : null;             index = f.tag.track != 0 ? (int?)f.tag.track : null;             year = f.tag.year != 0 ? (int?)f.tag.year : null;               comment = f.tag.comment;             copyright = f.tag.copyright;             lyrics = f.tag.lyrics;             title = f.tag.title;                               var artists = f.tag.artists.any() ? f.tag.artists : f.tag.albumartists;             artists = new entityhashset<artist>(artists.select(a => new artist(a.trim())));              composers = new entityhashset<artist>(f.tag.composers.select(c => new artist(c.trim())));              performers = new entityhashset<artist>(f.tag.performers.select(p => new artist(p.trim())));              var duplicatecomposers = composers.where(c => artists.any(a => a.id == c.id)).tolist();             (composers entityhashset<artist>).exceptwith(duplicatecomposers);             (composers entityhashset<artist>).unionwith(artists.where(a => duplicatecomposers.any(c => c.id == a.id)));              var artistscomposers = artists.union(composers).tolist();             var duplicateperformers = performers.where(p => artistscomposers.any(a => a.id == p.id)).tolist();             (performers entityhashset<artist>).exceptwith(duplicateperformers);             (performers entityhashset<artist>).unionwith(artistscomposers.where(a => duplicateperformers.any(c => c.id == a.id)));              var artistscomposersperformers = artistscomposers.union(performers).tolist();             if (!string.isnullorwhitespace(f.tag.conductor))             {                 conductor = new artist(f.tag.conductor.trim());                 var = artistscomposersperformers.firstordefault(c => c.id == conductor.id);                 if (a != null)                 {                     conductor = a;                 }             }              pictures = new entityhashset<picture>(f.tag.pictures.select(p => new picture(p)));              genres = new entityhashset<genre>(f.tag.genres.select(g => new genre(g.trim())));              if (!string.isnullorwhitespace(f.tag.album))             {                 album = new album(f.tag.album.trim(), artists)                 {                     trackcount = f.tag.trackcount != 0 ? (int?)f.tag.trackcount : null,                     albumcount = f.tag.disccount != 0 ? (int?)f.tag.disccount : null,                     index = f.tag.disc != 0 ? (int?)f.tag.disc : null,                      frontcover = pictures.singleordefault(p => p.type == picturetype.frontcover),                     backcover = pictures.singleordefault(p => p.type == picturetype.backcover)                  };             }           }     } 

code creating album:

public album(string name)         : this()     {         name = name;     }  public album(string name, ienumerable<artist> artists)         : this(name)     {         var sortedartists = artists.tolist();         sortedartists.sort();         artists = new entityhashset<artist>(sortedartists);          id = id.withhash(index.value);          foreach (var artist in sortedartists)         {             id = id.withhash(artist.id); // withhash extension method combine 2 hashcodes         }     } 

ids set so:

[required]     public string name     {         { return name; }         set         {             name = value;             id = name.tolowerinvariant().gethashcode();         }     } 

when insert single track whole graph database good. have check possible duplicates in artists, composers, performers , conductor. can replace references duplicates added objects same ids.

when have insert multiple tracks however, problems start arise. don't know how approach possible collisions.

for example. i'm adding 2 tracks album name "a". track 1 have genres "rock; blues", track 2 "blues; metal". album "a" must genres "rock; blues; metal". also, if album have different trackcount last 1 added determine value.

to achieve desired results have query database crazy in creation of single track object or there more elegant solution? tips me on right path appreciated.