@Override
	public String renderOrderByElement(String expression, String collation, String order, NullPrecedence nullPrecedence) {
		// DB2 FTW!
		if ( nullPrecedence == null || nullPrecedence == NullPrecedence.NONE ) {
			return super.renderOrderByElement( expression, collation, order, NullPrecedence.NONE );
		}

		if ( nullPrecedence == NullPrecedence.FIRST ) {
			// an explicit NullPrecedence request for NULLS FIRST
			if ( order == null || "asc".equals( order ) ) {
				// ASC + NULLS FIRST is ok, but unnecessary
				return super.renderOrderByElement( expression, collation, order, NullPrecedence.NONE );
			}
			else {
				// DESC + NULLS FIRST is not supported, so hack it
				return "order by case when " + expression + " is null then 0 else 1 end, " + expression + " desc";
			}
		}
		else {
			if ( order == null || "asc".equals( order ) ) {
				// ASC + NULLS LAST is not supported, so hack it
				return "order by case when " + expression + " is null then 1 else 0 end, " + expression + " asc";
			}
			else {
				// DESC + NULLS LAST is ok, but unnecessary
				return super.renderOrderByElement( expression, collation, order, NullPrecedence.NONE );
			}
		}
	}