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javasqloracle-databasewhile-loopresultset

Why is While (rs.next()) statement ending after 1st iteration?


I am using a SELECT statement to get data from a table and then insert it into another table. However the line "stmt.executeQuery(query);" is inserting the first line from the table then exits. When I comment this line out, the while loop loops through all the lines printing them out. The stacktrace isn't showing any errors. Why is this happening?

try{                
    String query = "SELECT * FROM "+schema_name+"."+table;

    rs = stmt.executeQuery(query);

    while (rs.next()) {

        String bundle = rs.getString("BUNDLE");
        String project_cd = rs.getString("PROJECT_CD");
        String dropper = rs.getString("DROPPER");
        String week = rs.getString("WEEK");
        String drop_dt = rs.getString("DROP_DT").replace(" 00:00:00.0","");

        query = "INSERT INTO INDUCTION_INFO (BUNDLE, PROJECT_CD, DROPPER, WEEK, DROP_DT) "
              + "VALUES ("
              + bundle+","
              + "'"+project_cd+"',"
              + dropper+","
              + week+","
              + "to_date('"+drop_dt+"','YYYY-MM-DD'))";

        System.out.println(query);

        stmt.executeQuery(query);
    }
}catch(Exception e){
    e.printStackTrace();
}

Solution

  • You are re-using the Statement that was used to produce rs on the last line of your loop.

    This will close the ResultSet rs. As stated in the documentation:

    A ResultSet object is automatically closed when the Statement object that generated it is closed, re-executed, or used to retrieve the next result from a sequence of multiple results.

    You need to use a second Statement object to execute the INSERT statements.