HP 3000 Manuals HP 3000 Manuals
ORDERS Database Model Program
Main Body of Program
BEGIN MAIN LINE
* OBJECTIVE: The main line contains the logic of this application.
* It displays all functions, accepts a selection,
* then calls the appropriate routines. The execution
* of this program stops after the database is closed.
*
* ACCESS: Not applicable.
*
* CALLED BY: Not applicable.
*
* CALLS: Open_The_Database
* Get_Sales_For_Date
* Get_A_Customer_Record
* Get_A_Product_Record
* List_All_Customers
* Add_A_Product
* Update_A_Customer
* Delete_A_Product
* Rewind_Customer_Set
* Get_Data_Item_Info
* Get_Error_And_Explain
* Close_The_Database
START LOOP
DISPLAY the list of functions
The following illustration depicts one way of displaying the list of
functions for this program.
Click here to view figure.
OBTAIN option <---- user input
If option = 1
Then CALL Open_The_Database
and RETURN
If option = 2
Then CALL Get_Sales_For_Date
and RETURN
If option = 3
Then CALL Get_A_Customer_Record
and RETURN
If option = 4
Then CALL Get_A_Product_Record
and RETURN
If option = 5
Then CALL List_All_Customers
and RETURN
If option = 6
Then CALL Add_A_Product
and RETURN
If option = 7
Then CALL Update_A_Customer
and RETURN
If option = 8
Then CALL Delete_A_Product
and RETURN
If option = 9
Then CALL Rewind_Customer_Set
and RETURN
If option = 10
Then CALL Get_Data_Item_Info
and RETURN
If option = 11
Then CALL Get_Error_And_Explain
and RETURN
If option = 12
Then CALL Close_The_Database
and RETURN
EXIT LOOP if option = 12
END LOOP
END MAIN LINE
Opening the Database
(USER SELECTS 1 TO OPEN THE DATABASE)
ROUTINE: Open_The_Database
* OBJECTIVE: This routine opens the ORDERS database in mode 1
* for this application.
*
* ACCESS: Mode 1 - Shared Modify Access (SMA) with locking required
*
* CALLED BY: Main Line
*
* CALLS: DBOPEN in mode 1 (SMA)
BEGIN ROUTINE
OBTAIN DBname <---- "__ORDERS;"
OBTAIN Password <---- "DO-ALL;"
CALL DBOPEN (DBname, Password, Mode1_SMA, Status)
ERROR CHECKING
END ROUTINE
Retrieving All the Records on a Chain (with Item Level Locking)
(USER SELECTS 2 TO RETRIEVE SALES DATA)
ROUTINE: Get_Sales_For_Date
* OBJECTIVE: This routine demonstrates chained access, forward chained
* read, and data item locking.
*
* The routine retrieves all sales records generated
* on a particular purchase date. The value for date is
* provided by the user and is used as the search item.
* Due to concurrency issues, a data item lock is acquired
* on all sales records identified by the date.
*
* ACCESS: Mode 1 - Shared Modify Access
*
* CALLED BY: Main Line
*
* CALLS: DBLOCK in mode 5 (unconditional)
* DBFIND in mode 1 (chained access)
* DBGET in mode 5 (forward chained read)
* DBUNLOCK in mode 1 (unlock)
BEGIN ROUTINE
Sales_Buffer is made up of:
Account
Stock#
Quantity
Price
Tax
Total
Purch-Date
Deliv-Date
Lock_Descriptor_Sales_Type is made up of:
Length_Of_Descriptor
Data_Set_Of_Descriptor
Data_Item_Of_Descriptor
Relative_Operator_For_Data_Item
Value_For_Data_Item
Lock_Descriptor_Sales_Array_Type is made up of:
Number_Of_Elements
Lock_Descriptor_Sales_Type
The following illustration shows the layout for a lock descriptor array
formats after the actual values have been assigned. Note that the date
is stored in YYMMDD format.
Click here to view figure.
OBTAIN Number_Of_Elements <---- 1
OBTAIN Length_Of_Descriptor <---- 21
OBTAIN Data_Set_Of_Descriptor <---- "SALES;"
OBTAIN Data_Item_Of_Descriptor <---- "PURCH-DATE;"
OBTAIN Relative_Operator_For_Data_Item <---- "_="
OBTAIN Value_For_Data_Item <---- "881012"
OBTAIN List <---- "@;"
OBTAIN Search_Item_Name <---- "PURCH-DATE;"
OBTAIN Search_Item_Value <---- "881012"
CALL DBLOCK (DBname, Lock_Descriptor_Sales_Array_Type,
Mode5_Unconditional, Status)
ERROR CHECKING
CALL DBFIND (DBname, Sales_Detail, Mode1_Chained_Read,
Status, Search_Item_Name, Search_Item_Value)
ERROR CHECKING
START LOOP
CALL DBGET (DBname, Sales_Detail, Mode5_Forward, Status,
List, Sales_Buffer, Not_Used_Parm)
ERROR CHECKING
DISPLAY the Sales_Buffer
____________________________________________________________________
Account Stock# Quantity Price Tax Total Purch-Date Deliv-Date
EXIT LOOP if end of chain
END LOOP
CALL DBUNLOCK (DBname, Lock_Desc_Array, Mode1_Unlock, Status)
ERROR CHECKING
END ROUTINE
Retrieving a Data Entry Using a Record Number
(USER SELECTS 3 TO RETRIEVE CUSTOMER DATA)
ROUTINE: Get_A_Customer_Record
* OBJECTIVE: This routine demonstrates directed access by retrieving
* a customer record with a known record number. Note
* that the record number is first obtained using a DBGET
* call, which in this case is a calculated mode 7.
*
* ACCESS: Mode 1 - Shared Modify Access
*
* CALLED BY: Main Line
*
* CALLS: DBGET in mode 7 (calculated read)
* DBGET in mode 4 (directed read)
BEGIN ROUTINE
Customer_Buffer is made up of:
Account
Last-Name
First-Name
Initial
Street-Address
City
State
Zip
Credit-Rating
OBTAIN List <---- "@;"
OBTAIN Key_Item_Value <---- 315578
CALL DBGET (DBname, Customer_Master, Mode7_Calculated, Status, List,
Customer_Buffer, Key_Item_Value)
ERROR CHECKING
OBTAIN Record_Num <---- Status [element 3]
CALL DBGET (DBname, Customer_Master, Mode4_Directed, Status, List,
Customer_Buffer, Record_Num)
ERROR CHECKING
DISPLAY the Customer_Buffer
____________________________________________________________________
Account Last-Name First-Name Initial Street-Address City. . .
END ROUTINE
Retrieving Master Data Using a Key Value
(USER SELECTS 4 TO RETRIEVE PRODUCT DATA)
ROUTINE:Get_A_Product_Record
* OBJECTIVE: This routine demonstrates calculated access by
* retrieving a product record from a master data
* set based on a user-defined key item value.
*
* ACCESS: Mode 1 - Shared Modify Access
*
* CALLED BY: Main Line
*
* CALLS: DBGET in mode 7 (calculated read)
BEGIN ROUTINE
Product_Buffer is made up of:
Stock#
Description
OBTAIN List <---- "@;"
OBTAIN Key_Item_Value <---- "STK30040"
CALL DBGET (DBname, Product_Master, Mode7_Calculated, Status, List,
Product_Buffer, Key_Item_Value)
ERROR CHECKING
DISPLAY the Product_Buffer
____________________________________________________________________
Stock# Description
END ROUTINE
Retrieving Data Serially (with Set Level Locking)
(USER SELECTS 5 TO RETRIEVE CUSTOMER DATA)
ROUTINE: List_All_Customers
* OBJECTIVE: This routine demonstrates serial access by listing
* all customer records. For the sake of consistency,
* the data set is locked for exclusive access,
* then the data is read serially.
*
* ACCESS: Mode 1 - Shared Modify Access
*
* CALLED BY: Main Line
*
* CALLS: DBLOCK in mode 3 (unconditional)
* DBGET in mode 2 (forward read)
* DBUNLOCK in mode 1 (unlock)
BEGIN ROUTINE
Customer_Buffer is made up of:
Account
Last-Name
First-Name
Initial
Street-Address
City
State
Zip
Credit-Rating
CALL DBLOCK (DBname, Customer_Master, Mode3_Unconditional, Status)
ERROR CHECKING
OBTAIN List <---- "Account, Last-Name, First-Name, Initial;"
START LOOP
CALL DBGET (DBname, Customer_Master, Mode2_Forward, Status, List,
Customer_Buffer, Not_Used_Parm)
ERROR CHECKING
DISPLAY List
____________________________________________________________________
Account Last-Name First-Name Initial
EXIT LOOP if first word of Status buffer <> 0
END LOOP
CALL DBUNLOCK (DBname, Customer_Master, Mode1_Unlock, Status)
ERROR CHECKING
END ROUTINE
Adding an Entry
(USER SELECTS 6 TO DO A PUT)
ROUTINE: Add_A_Product
* OBJECTIVE: This routine adds one entry to the Product master data
* set. After obtaining user input, the data set is locked
* for exclusive access. A transaction starts, and
* new values are added by a call to DBPUT. At the end
* of the routine, the transaction is ended and locks
* are released.
*
* ACCESS: Mode 1 - Shared Modify Access
*
* CALLED BY: Main Line
*
* CALLS: DBLOCK in mode 3 (unconditional)
* DBBEGIN in mode 1 (transaction begin)
* DBPUT in mode 1 (put)
* DBEND in mode 1 (transaction end)
* DBUNLOCK in mode 1 (unlock)
BEGIN ROUTINE
Product_Buffer is made up of:
Stock#
Description
OBTAIN Stock# <---- user input
OBTAIN Description <---- user input
OBTAIN List <---- "@;"
CALL DBLOCK (DBname, Product_Master, Mode3_Unconditional, Status)
ERROR CHECKING
OBTAIN Text <---- "Add entry to Product set Begin__"
OBTAIN Textlen <---- 16
CALL DBBEGIN (DBname, Text, Mode1_Xbegin, Status, TextLen)
ERROR CHECKING
CALL DBPUT (DBname, Product_Master, Mode1_Put, Status, List,
Product_Buffer)
ERROR CHECKING
OBTAIN Text <---- "Add entry to Product set End"
OBTAIN Textlen <---- 14
CALL DBEND (DBname, Text, Mode1_Xend, Status, Textlen)
ERROR CHECKING
CALL DBUNLOCK (DBname, Product_Master, Mode1_Unlock, Status)
ERROR CHECKING
END ROUTINE