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(Continued from previous question...)
Simple Non-Updatable ResultSets?
Here is an excerpt from a sample JDBC application that generates a ResultSet with a simple SELECT statement and then processes the rows.
Connection conn = DriverManager.getConnection(
"jdbc:derby:sample");
Statement s = conn.createStatement();
s.execute("set schema 'SAMP'");
//note that autocommit is on--it is on by default in JDBC
ResultSet rs = s.executeQuery(
"SELECT empno, firstnme, lastname, salary, bonus, comm "
+ 12 "FROM samp.employee");
/** a standard JDBC ResultSet. It maintains a
* cursor that points to the current row of data. The cursor
* moves down one row each time the method next() is called.
* You can scroll one way only--forward--with the next()
* method. When auto-commit is on, after you reach the
* last row the statement is considered completed
* and the transaction is committed.
*/
System.out.println( "last name" + "," + "first name" + ": earnings");
/* here we are scrolling through the result set
with the next() method.*/
while (rs.next()) {
// processing the rows
String firstnme = rs.getString("FIRSTNME");
String lastName = rs.getString("LASTNAME");
BigDecimal salary = rs.getBigDecimal("SALARY");
BigDecimal bonus = rs.getBigDecimal("BONUS");
BigDecimal comm = rs.getBigDecimal("COMM");
System.out.println( lastName + ", " + firstnme + ": "
+ (salary.add(bonus.add(comm))));
}
rs.close();
// once we've iterated through the last row,
// the transaction commits automatically and releases
//shared locks
s.close();
(Continued on next question...)
