Question

PFB我使用的代码：

ResultSet rs1 = stmt.executeQuery("select dfd.document_id,dfd.country_id,dfi.folder_name from dossier_folder_documents dfd,dossier_folder_info dfi where dfd.fk_dossier_folder_id=dfi.pk_dossier_folder_id and dfd.is_core is null and dfd.action='N' and dfd.fk_dossier_basic_info_id in (select pk_dossier_id from dossier_basic_info where dossier_id= '"+vdlist.get(g)+"' and (dfd.document_id,dfi.folder_name) not in(select dfd.document_id,dfi.folder_name from dossier_folder_documents dfd,dossier_folder_info dfi where dfd.fk_dossier_folder_id=dfi.pk_dossier_folder_id  and dfd.fk_dossier_basic_info_id in (select pk_dossier_id from dossier_basic_info where dossier_id= '"+sdlist.get(g)+"' and data_state='C')))");



ResultSet rs2 = stmt.executeQuery("select dfd.document_id,dfd.country_id,dfi.folder_name from dossier_folder_documents dfd,dossier_folder_info dfi where dfd.fk_dossier_folder_id=dfi.pk_dossier_folder_id and dfd.is_core is null and dfd.action='O' and dfd.fk_dossier_basic_info_id in (select pk_dossier_id from dossier_basic_info where dossier_id='"+vdlist.get(g)+"') and (dfd.document_id,dfi.folder_name) in (select dfd.document_id,dfi.folder_name from dossier_folder_documents dfd,dossier_folder_info dfi where  dfd.fk_dossier_folder_id=dfi.pk_dossier_folder_id  and dfd.fk_dossier_basic_info_id in (select pk_dossier_id from dossier_basic_info where dossier_id='"+sdlist.get(g)+"' and data_state='C'))");

            ResultSetMetaData rsmd1 = rs1.getMetaData();
            //ResultSetMetaData rsmd2 = rs2.getMetaData();
            String temp5 = new String();

            for(int f=1;f<=rsmd1.getColumnCount();f++)
                {
                    data3+=rsmd1.getColumnName(f)+"/ /";}
                    temp4=data3;
                    data3="";

                    while(rs1.next())
                        {
                            System.out.println("In here...");
                            num2=g;
                            for(int x=1;x<=rsmd1.getColumnCount();x++)
                                {
                                    temp5+=rs1.getString(x)+"/ /";

                                }
                            String data5 = new String();
                            data5=temp5;
                            sublist1.add(data5);
                            //System.out.println(sublist);
                            errvdlist.add(vdlist.get(num2));
                            errsdlist.add(sdlist.get(num2));
                            System.out.println("Validation Dossier ID for New Corruption: "+vdlist.get(num2));
                            System.out.println("Submission Dossier ID for New Corruption: "+sdlist.get(num2));

                        }

                    while(rs2.next() )
                    {
                        num2=g;
                        for(int x=1;x<=rsmd1.getColumnCount();x++)
                            {

                                temp6+=rs2.getString(x)+"/ /";
                            }

                        //String data6 = new String();

                        data6=temp6;

                        sublist2.add(data6);
                        //System.out.println(sublist);
                        errvdlist.add(vdlist.get(num2));
                        errsdlist.add(sdlist.get(num2));
                        System.out.println("Validation Dossier ID for Old: "+vdlist.get(num2));
                        System.out.println("Submission Dossier ID for Old: "+sdlist.get(num2));

                    }

                }

我必须执行两个查询，并且使用了两个结果集：rs1和rs2。在我的输出中，执行了rs2的while循环，但未执行rs1。我最初以为用于rs1的查询存在问题，但事实并非如此。不会执行要打印“在这里...”的print语句，这意味着它甚至不会进入循环。有什么建议吗？

Answer 1

来自ResultSet javadoc：

一个ResultSet对象自动关闭，当生成它的Statement对象关闭，重新执行或用于从多个结果序列中检索下一个结果时。

因此，基本上，Statement一次只能给您一个ResultSet，因此在执行第二个查询时，您会丢失第一个结果。

使用两个Statement实例可以使两个ResultSet一起打开。

ResultSet在Java中不起作用

1 个答案: