Adding two ResultSets in java

Question

How can we add two resultsets in java ?

Answer 1

screen_simu wrote:
Is it something we can do in java?OP, if you can do it in SQL, that likely would be better. On the other hand, do you mean that want to add the results from two resultsets that might perchance be different? IOW ... if both ResultSets produce the same columns, then a UNION join in SQL:select
    tableA.empl_name,
    tableA.empl_id
  from tableA
UNION
select
    tableB.empl_name,
    tableB.empl_id
  from tableBBut, if you want to select out specific columns from differing RS's, then you might want to do this:
  List<Empl> empList = new ArrayList<Empl>();
  public class Empl {
    private String empl_id;
    private String empl_name;
    private Double empl_wage;
    public void setName(String name) {
      empl_name = name;
// ... etc, other method implementations ...
// ... SQL stuff ...
  String sqlA =
     "select"
    +"    tableA.empl_id,"
    +"    tableA.empl_wages"
    +"  from tableA";
// ... rsA is the ResultSet from the tableA selection
  Empl empl = null;
  while (rsA.next()) {
    empl.setID(rsA.getString(1));
    empl.setWage(rsA.getDouble(2));
    empl.setName(processTableB(empl.getID()));
    empList.add(empl);  // new Empl Object for each employee
  public String processTableB(String id) {
    String name = null;
  String sqlB =
    "select"
    +"    tableB.empl_name"
    +" from tableB"
    +" where tableB.empl_id = ?"
// ... set up PreparedStatement ... using passed in id
// ... process ...
  while (rsB.next()) {
    name = rsB.getString(1);
  return( name );
}Above code untested, but hopefully you get the idea.