Android SQLite dynamically insert sorting (ASD or DESC), is it possible?

Question

I'm trying to use one method for dao (Room) to get items by a specific sorting dynamically, but compiler gives an error for the next SQL query

So it's not possible? Do I have to create duplicate methods with different sorting?

Answer 1

you can not perform if and else logic in the sqlite query

You should use @RawQuery like this:

 @Dao
 interface RawDao {
   @RawQuery
   fun getTestItems(SupportSQLiteQuery query): DataSource.Factory
 }

 // Usage of RawDao
 // for example set: restOfQuery = sortBy + "ASC"
 val query = SimpleSQLiteQuery(
     "SELECT * FROM Items ORDER BY ?",
     new Object[]{ restOfQuery }); 
 val result = rawDao.getTestItems(query);

Or another way is that you use multiple functions for multiple orderings.