#397 | Add support doc for method getNoteById() in NotesDao.kt

noty-android/data/local/src/main/java/dev/shreyaspatil/noty/data/local/dao/NotesDao.kt

@@ -26,6 +26,18 @@ import kotlinx.coroutines.flow.Flow
 @Dao
 interface NotesDao {
 
+    /**
+     * The return type of this method is nullable because internally it throws an error if
+     * entity doesn't exist.
+     *
+     * Official docs says
+     *
+     * * When the return type is Flow<T>, querying an empty table throws a null pointer exception.
+     * * When the return type is Flow<T?>, querying an empty table emits a null value.
+     * * When the return type is Flow<List<T>>, querying an empty table emits an empty list.
+     *
+     * Refer: https://developer.android.com/reference/androidx/room/Query
+     */
     @Query("SELECT * FROM notes WHERE noteId = :noteId")
     fun getNoteById(noteId: String): Flow<NoteEntity?>