I have this structure of my Firebase Database
Each library can have several albums. How can I display the albums for each library?
the albumsPerLib:
first element is the library key, and underneath each library key, I store the albums keys, that belong to it.
But I'm not used to NoSQL and can't figure how to join the tables to display the albums for each library.
so this works:
getAlbumsThatBelongToLib(libKey:string):Observable<Album[]>{
//get the keys for the lib albums
const albumsPerLib$ = this.db.list(`albumsPerLib/${libKey}`);
//map the returned list of keys
//and get their details from the albums node
return albumsPerLib$
.map((albumKeys) => albumKeys
.map( (albumKey) => {
return this.db.object(`albums/${albumKey.$key}`)
}))
.flatMap((res) => {
return Observable.combineLatest(res);
});
}
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