java - 不完整的结果集数据

Question

    Comment comment;
     ArrayList<Comment> commentList = null;

     try{
         ConnectionFactory myFactory = ConnectionFactory.getFactory();
         Connection conn = myFactory.getConnection();
         int i = 1; int j = 1; int k = 1;

         PreparedStatement pstmt = conn.prepareStatement("SELECT * FROM COMMENT WHERE deletestatus = 0 and workid = ?");

         PreparedStatement pstmtLName = conn.prepareStatement("SELECT * FROM LEADER WHERE leaderid = ?");

         PreparedStatement pstmtMName = conn.prepareStatement("SELECT * FROM MEMBER WHERE memberid = ?");

         pstmt.setInt(i++, Integer.parseInt(projid));

         ResultSet rs = pstmt.executeQuery();
         System.out.print(rs);
         commentList = new ArrayList<Comment>();
         while(rs.next())
            {
                comment = new Comment();
                comment.setDetails(rs.getString("details"));
                comment.setDateadded(rs.getTimestamp("dateadded"));
                comment.setUrgency(rs.getInt("urgency"));



                if(rs.getInt("leaderid") != 0){
                    comment.setLeaderid(rs.getInt("leaderid"));

                    pstmtLName.setInt(j++, rs.getInt("leaderid"));

                    ResultSet rs2 = pstmtLName.executeQuery();


                    if(rs2.next()){
                    comment.setFullname(rs2.getString("firstname") +" " + rs2.getString("lastname"));
                    }
                }
                if(rs.getInt("memberid") != 0) {
                    comment.setMemberid(rs.getInt("memberid"));

                    System.out.print("in the loop");

                    pstmtMName.setInt(j++, rs.getInt("memberid"));
                    ResultSet rs3 = pstmtMName.executeQuery();

                    if(rs2.next()){
                    comment.setFullname(rs3.getString("firstname") +" " + rs3.getString("lastname"));
                    }

                }   

                comment.setProjid(Integer.parseInt(projid));
                commentList.add(comment);
            }



         return commentList;
     }

上面代码的问题是它只返回结果集的第一个结果。

当我删除 WHILE(RS.NEXT) 子句中的两个 IF 子句时，它返回了所有需要的结果但不完整的信息，因为我还需要在 if 语句中查询。

如果你们知道确切的问题，请提供帮助，如果你们需要更多信息，请告诉我。谢谢!

Answer 1

这里，问题似乎在

pstmtLName.setInt(j++, rs.getInt("leaderid"));
pstmtMName.setInt(j++, rs.getInt("memberid"));

j 的值会随着每个真条件的增加而增加，直到循环迭代。 因此，它会增加您准备好的语句的parameterIndex。

应该是

pstmtLName.setInt(1, rs.getInt("leaderid"));
pstmtMName.setInt(1, rs.getInt("memberid"));