类别查询 父节点标题 sql

/* public SqlDataReader GetUserNeedsByUserResType(int userResType,int pageIndex) { this.OpenConn(); this.Comm.CommandText = "select top 20 * from Questions C, (select A.ID as ID,A.PID AS PID,A.TITLE AS TITLE,B.Title as PTitle from Category A left join Category B ON A.PID=B.ID where A.PID=B.ID) D where C.type=D.ID and C.type=" + userResType + " and C.questionID not in (select top " + pageIndex * 20 + " C.questionID from Questions C, (select A.ID as ID,A.PID AS PID,A.TITLE AS TITLE,B.Title as PTitle from Category A left join Category B ON A.PID=B.ID where A.PID=B.ID) D where C.type=D.ID and C.type=" + userResType + " order by questionTime desc) order by questionTime desc"; return this.Comm.ExecuteReader(CommandBehavior.CloseConnection); }*/--select A.ID as ID,A.PID AS PID,A.TITLE AS TITLE,B.Title as PTitle from Category A left join Category B ON A.PID=B.ID select *,C.title as questionTitle from Questions C, (select A.ID as ID,A.PID AS PID,A.Title AS Title,B.Title as PTitle from Category A left join Category B ON A.PID=B.ID where A.PID=B.ID) Dwhere C.type=D.ID and C.type=63