我写了一个函数, 想要把删除和插入联合成一个事务, 要么全执行, 要么都不执行?
不知道 怎么写?
public boolean addBatch(int roleID, int permissionID[]) { try { // 先删除所有的数据, 然后再插入所有的数据
sSQL = "delete from RolesPermissions where RoleID=" + roleID;
stmt = conn.createStatement();
rs = stmt.executeQuery(sSQL); PreparedStatement stmt = conn
.prepareStatement("INSERT INTO RolesPermissions VALUES(?,?,?)"); for (int i = 0; i < permissionID.length; i++) {
stmt.setInt(2, roleID);
stmt.setInt(1, permissionID[i]);
stmt.addBatch();
}
int[] counts=stmt.executeBatch(); } catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return flag; }
不知道 怎么写?
public boolean addBatch(int roleID, int permissionID[]) { try { // 先删除所有的数据, 然后再插入所有的数据
sSQL = "delete from RolesPermissions where RoleID=" + roleID;
stmt = conn.createStatement();
rs = stmt.executeQuery(sSQL); PreparedStatement stmt = conn
.prepareStatement("INSERT INTO RolesPermissions VALUES(?,?,?)"); for (int i = 0; i < permissionID.length; i++) {
stmt.setInt(2, roleID);
stmt.setInt(1, permissionID[i]);
stmt.addBatch();
}
int[] counts=stmt.executeBatch(); } catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return flag; }
***************************************public class OrderHandler extends HttpServlet { public void doPost(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {
res.setContentType("text/plain");
PrintWriter out = res.getWriter(); Connection con = null;
try {
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
con = DriverManager.getConnection("jdbc:odbc:ordersdb", "user", "passwd"); // Turn on transactions
con.setAutoCommit(false); Statement stmt = con.createStatement();
stmt.executeUpdate(
"UPDATE INVENTORY SET STOCK = (STOCK - 10) WHERE PRODUCTID = 7");
stmt.executeUpdate(
"UPDATE SHIPPING SET SHIPPED = (SHIPPED + 10) WHERE PRODUCTID = 7"); chargeCard(); // method doesn't actually exist... con.commit();
out.println("Order successful! Thanks for your business!");
}
catch (Exception e) {
// Any error is grounds for rollback
try {
con.rollback();
}
catch (SQLException ignored) { }
out.println("Order failed. Please contact technical support.");
}
finally {
// Clean up.
try {
if (con != null) con.close();
}
catch (SQLException ignored) { }
}
}
}