My problem: I'm not sure why this Android Room query is not returning results. I thought I understood the proper coding and it seems quite simple. If I pass this same query directly to the same database using SQLiteStudio, I get results.
The calling code (I hardcoded the string 'truth' to test it):
List<Integer> tableIDs = researchDatabase.getCommentsDao().customSearchCommentsTable("truth");
The DAO code (Contained in the CommentsDao):
@Query("SELECT CommentID FROM Comments WHERE Comment LIKE :value")
List<Integer> customSearchCommentsTable(String value);
What I have done: I'm new to Android Room, but I have been using all examples and lessons from Android Developers (developer.android.com) and reviewed and applied many posts here at stackoverflow closely related but I cannot get any results to return. When I step through the code, the actual Android Room code does not seem to be binding the variable string to the statement though I can see the argument string being identified and passed properly, which isn't code that I have written, or at least I never see the resulting binding string with my variable data, I only see this:
SELECT CommentID FROM Comments WHERE Comment LIKE ?
What my goal is: This is actually the first step to creating a query to handle a multiple LIKE query similar to this, which I think will require a @RawQuery setup. Right now, I cannot get the simple thing to work.
What happens in the @Query wrapper: I realize I may be naive and wrong here, but below I can see the argument and statement both get passed, but it does not appear as if the "_statement.bindString" is actually binding the ":value" ('truth') to the statement and is returning 0 results.
This is the solution provided by the Android Room development team:
@Query("SELECT CommentID FROM Comments WHERE Comment LIKE '%' || :value || '%'")
List<Integer> customSearchCommentsTable(String value);
The irony is that the development team could not get their posted code example to work. By the time they responded I had already created a workaround using a @RawQuery method to create the proper SQL syntax.