//
// Update_CustomerMaster_Records()
//
// Update one record under locking control to demonstrate the effects
// of locking
//
static void Update_CustomerMaster_Record()
{
Console.WriteLine("\tUpdate Record...");
try
{
// enable session-wide lock flag
MySession.Lock(LOCK_MODE.WRITE_BLOCK_LOCK);
MyRecord.Clear();
MyRecord.SetFieldAsString(0, "1003");
// find record by customer number
if (MyRecord.Find(FIND_MODE.EQ))
{
MyRecord.SetFieldAsString(4, "KEYON DOOLING");
// rewrite record
MyRecord.Write();
Console.WriteLine("\tPress <ENTER> key to unlock");
Console.ReadLine();
}
// reset session-wide locks
MySession.Unlock();
}
catch (CTException E)
{
Handle_Exception(E);
}
}
static void Add_Transactions()
{
ORDER_DATA[] orders = new ORDER_DATA[3];
orders[0] = new ORDER_DATA("09/01/2002", "09/05/2002", "1", "1001");
orders[1] = new ORDER_DATA("09/02/2002", "09/06/2002", "2", "9999"); // bad customer number
orders[2] = new ORDER_DATA("09/22/2002", "09/26/2002", "3", "1003");
int nOrders = orders.Length;
ORDERITEM_DATA[] items = new ORDERITEM_DATA[6];
items[0] = new ORDERITEM_DATA("1", 1, 2, "1");
items[1] = new ORDERITEM_DATA("1", 2, 1, "2");
items[2] = new ORDERITEM_DATA("2", 1, 1, "3");
items[3] = new ORDERITEM_DATA("2", 2, 3, "4");
items[4] = new ORDERITEM_DATA("3", 1, 2, "3");
items[5] = new ORDERITEM_DATA("3", 2, 2, "99"); // bad item number
int nItems = items.Length;
CTDate orderdate = new CTDate();
CTDate promdate = new CTDate();
int savepoint;
int j = 0;
Delete_Records(recordCustOrdr);
Delete_Records(recordOrdrItem);
Console.WriteLine("\tAdd transaction records...");
// process orders
for (int i = 0; i < nOrders; i++)
{
// start a transaction
MySession.Begin();
try
{
recordCustOrdr.Clear();
// populate record buffer with order data
orderdate.StringToDate(orders[i].orderdate, DATE_TYPE.MDCY_DATE);
promdate.StringToDate(orders[i].promdate, DATE_TYPE.MDCY_DATE);
recordCustOrdr.SetFieldValue(0, orderdate);
recordCustOrdr.SetFieldValue(1, promdate);
recordCustOrdr.SetFieldAsString(2, orders[i].ordernum);
recordCustOrdr.SetFieldAsString(3, orders[i].custnum);
// add order record
recordCustOrdr.Write();
}
catch (CTException E)
{
// abort transaction on error
Handle_Exception(E);
}
// set transaction savepoint
savepoint = recordCustOrdr.SetSavePoint();
// process order items
while (items[j].ordernum == orders[i].ordernum)
{
try
{
recordOrdrItem.Clear();
// populate record buffer with order item data
recordOrdrItem.SetFieldValue(0, items[j].seqnumber);
recordOrdrItem.SetFieldValue(1, items[j].quantity);
recordOrdrItem.SetFieldAsString(2, items[j].ordernum);
recordOrdrItem.SetFieldAsString(3, items[j].itemnum);
// add order item record
recordOrdrItem.Write();
// check that item exists in ItemMaster table
recordItemMast.Clear();
recordItemMast.SetFieldAsString(2, items[j].itemnum);
if (!recordItemMast.Find(FIND_MODE.EQ))
{
// if not found, restore back to previous savepoint
recordItemMast.RestoreSavePoint(savepoint);
}
else
{
// set transaction savepoint
savepoint = recordItemMast.SetSavePoint();
}
}
catch (CTException E)
{
// abort transaction on error
Handle_Exception(E);
}
// bump to next item
j++;
// exit the while loop on last item
if (j >= nItems)
{
break;
}
}
// check that customer exists in CustomerMaster table
recordCustMast.Clear();
recordCustMast.SetFieldAsString(0, orders[i].custnum);
// commit or abort the transaction
if (!recordCustMast.Find(FIND_MODE.EQ))
{
MySession.Abort();
}
else
{
MySession.Commit();
}
}
}
//
// Manage()
//
// Populates table and perform a simple query
//
static void Manage()
{
int quantity;
double price, total;
string itemnumb, custnumb, ordrnumb, custname;
bool isOrderFound, isItemFound;
Console.WriteLine("MANAGE");
// populate the tables with data
Add_CustomerMaster_Records();
Add_CustomerOrders_Records();
Add_OrderItems_Records();
Add_ItemMaster_Records();
// perform a query:
// list customer name and total amount per order
// name total
// @@@@@@@@@@@@@ $xx.xx
// for each order in the CustomerOrders table
// fetch order number
// fetch customer number
// fetch name from CustomerMaster table based on customer number
// for each order item in OrderItems table
// fetch item quantity
// fetch item number
// fetch item price from ItemMaster table based on item number
// next
// next
Console.WriteLine("\n\tQuery Results");
try
{
// get the first order
isOrderFound = recordCustOrdr.First();
while (isOrderFound) // for each order in the CustomerOrders table
{
// fetch order number
ordrnumb = recordCustOrdr.GetFieldAsString(2);
// fetch customer number
custnumb = recordCustOrdr.GetFieldAsString(3);
// fetch name from CustomerMaster table based on customer number
recordCustMast.Clear();
recordCustMast.SetFieldAsString(0, custnumb);
if (!recordCustMast.Find(FIND_MODE.EQ))
{
continue; // not possible in our canned example
}
custname = recordCustMast.GetFieldAsString(4);
// fetch item price from OrderItems table
recordOrdrItem.Clear();
recordOrdrItem.SetFieldAsString(2, ordrnumb);
// define a recordset to scan only items applicable to this order
recordOrdrItem.RecordSetOn(6);
isItemFound = recordOrdrItem.First();
total = 0;
while (isItemFound) // for each order item in OrderItems table
{
// fetch item quantity
recordOrdrItem.GetFieldValue(1, out quantity);
// fetch item number
itemnumb = recordOrdrItem.GetFieldAsString(3);
// fetch item price from ItemMaster table based on item number
recordItemMast.Clear();
recordItemMast.SetFieldAsString(2, itemnumb);
recordItemMast.Find(FIND_MODE.EQ);
recordItemMast.GetFieldValue(1, out price);
// calculate order total
total += (price * quantity);
isItemFound = recordOrdrItem.Next();
}
recordOrdrItem.RecordSetOff();
// output data to stdout
Console.WriteLine("\t\t{0,-20}{1,-8}", custname, total);
// read next order
if (!recordCustOrdr.Next())
{
isOrderFound = false;
}
}
}
catch (CTException E)
{
Handle_Exception(E);
}
}