Manupulate the data from the database and update it back

Question

hi. i was wondering if it is possible to manupulate the data that we get from the resuletSet and do some manupulation and and again update it back to the same row and column. i tried to do it but could not get it. eg. i want to increase the salary by 10% for all the employee in the salary table. i dont want to use the SQL statement. instead i want to use the java program to increase the salary by 10%.
what i did was, i selected all the records in the table in the resultset and then i stored the salary one by one through the loos using rs.next() and manupulated the salary by the formula
salary=salary + salary*10/100.
then i want to update all the employee with this new salary. i dont know whether it is possible or not.
i tried to have an UPDATE statement in the while loop with rs.next with the condition but the loop gets terminated once it tries to execute the UPDATE statment and doesnot give any result.
any help or suggestion will be highly appreciated.

Answer 1

Here's the general long hand way of doing it. You should also look into your JDBC driver and the use of updateable ResultSets for more effeciency.
public class SalaryObject {
    private int rowId = 0;
    private double salary = 0.0;
    public void setRowId(int rowId) {
        this.rowId = rowId;
    public int getRowId() {
        return rowId;
    public void setSalary(double salary) {
        this.salary = salary;
    public double getSalary() {
        return salary;
}Withing your dataccess class:
Vector salaries = new Vector();
ResultSet rs = statement.executeQuery("SELECT rowId, salary FROM YOUR_SALARY_TABLE)
if (rs != null) {
    while(rs.next()) {
        SalaryObject salaryObject = new SalaryObject();
        salaryObject.setRowId(rs.getInt("rowId"));
        double newSalary = rs.getDouble("salary");
        newSalary += newSalary*10/100;
        salaryObject.setSalary(newSalary);
        salaries.add(salaryObject);
    Iterator iter = salaries.iterator();
    while(iter.hasNaxt()) {
        SalaryObject salaryObject = (SalaryObject) iter.next();
        updateSalary(salaryObject.getRowId, salaryObject.getSalary);
    public int updateSalary(int rowId, double newSalary) {
        Connection con = new java.sql.Connection();
        String sql = "UPDATE YOUR_SALARY_TABLE SET salary = ? WHERE rowId = ?"
        PreparedStatement pStmt = con.prepareStatement(sql);
        int success = 0;
        try {
            pStmt.setDouble(1, newSalary);
            pStmt.setInt(2, rowId);
            success = pStmt.executeUpdate();
        } catch (SQLException sqle) {
            // handle exception
        } finally {
            try {
                if (pStmt != null) pStmt.close();
                if (con != null) con.close();
            } catch (SQLException sqle) {}
    }