Java String concatenation with BaseColumns._ID brings an error

In eclipse as soon as i type this out:

BaseColumns._ID, + "=?"

I get:

The operator + is undefined for the argument type(s) String

How is that possible, they are both Strings aren't they?

now here is documentation for BaseColumns._ID:

public static final String _ID

the code I am writin开发者_如何学Pythong is:

public void deteleProfile(Long id) throws SQLException {
        SQLiteDatabase db = helper.getWritableDatabase();
        Integer i = db.delete(ProlificDatabase.TABLE, BaseColumns._ID, + "=?", new String[] {id.toString()});
        Log.d(TAG, i + " records deleted where id is " + id);

You've got a rogue comma:

BaseColumns._ID, + "=?"

should probably be

BaseColumns._ID + "=?

Otherwise it's trying to use + "=?" as a stand-alone argument with the + acting as a unary operator.

Do you mean BaseColumns._ID + "=?" instead of BaseColumns._ID, + "=?"?

The compiler just sees the left hand side of the + operator as being empty.

See this documentation on how to use the db.delete method. Instead of BaseColumns._ID, + "=?" - you should be doing this:

Integer i = db.delete(ProlificDatabase.TABLE, BaseColumns._ID + "=?", new String[] {id.toString()});

Lovely extra , (comma)... love the commas for what they are, meaning a separator between expressions and a pain ... for when you overlook them!