This tutorial takes you through the process of migrating a DB2 application to a SQL Server application, using HCOSS to convert labeled duration calculations and managing date formats.
SQL Server does not support labeled duration calculations directly. HCOSS handles the conversion to T-SQL to implement the DB2 syntax of an EXEC SQL statement using labeled durations.
This tutorial also demonstrates binding the application using a post-build event in
Eclipse.
Requirements
Before attempting this tutorial, you must first complete the following tutorials to ensure you have an established SQL Server database named HCO_Test containing the required PROD and TEST schemas and a connection to the HCO_Test database:
- Tutorial: Create a SQL Server Database
- Tutorial: Create a Database Connection
- Tutorial: DB2 Database Migration or
Tutorial: Setup for Application Migration Tutorials
Eclipse Project
The
Eclipse project we provide for this tutorial contains
the
LBLDURATION project, which is a native COBOL project.
Phase 1: Start
Enterprise Developer and HCO for SQL Server
If
Enterprise Developer and HCOSS for SQL Server tools are already running, skip this phase.
- Start
Enterprise Developer as an administrator. This procedure varies depending on your Windows version. If you need instructions, see
To start
Enterprise Developer as an administrator.
- In
Eclipse, click
Run > Tools > HCO for SQL Server.
Phase 2: Analyze, Build, and Bind the Native Application
- Analyze the Native Application
-
- From the Eclipse IDE, click
File >
Import.
- Expand
General, and select
Existing Projects into Workspace; then click
Next.
- Select
Set root directory; then browse to the
%PUBLIC%\Documents\Micro Focus\Enterprise Developer\Samples\Mainframe\Eclipse\SQL\hcoss\LBLDURATION directory, and click
OK.
- On the
Projects list, check
LBLDURATION.
- Check
Copy projects into workspace.
- Click
Finish. Eclipse loads the project and builds it automatically.
- From the
COBOL Explorer,
expand
LBLDURATION > COBOL Programs; then double-click the
LBLDURATION.cbl file to view its contents. Pay particular attention to the following EXEC SQL statement:
EXEC SQL
DECLARE CSR69 CURSOR FOR SELECT
A.PROJNO
,A.PROJNAME
,A.PRSTDATE
,A.PRENDATE
,(((DAYS(A.PRENDATE) - DAYS(A.PRSTDATE) ) / 7) + 1) * 40
AS MANHOURS
FROM PROJ A
ORDER BY A.PROJNAME
END-EXEC
This contains your labeled duration calculation:
,(((DAYS(A.PRENDATE) - DAYS(A.PRSTDATE) ) / 7) + 1) * 40
In this case, you are using the DAYS labeled duration in a calculation where you:
- Start with the number of days between the start and end date for projects
- Divide that number by 7 to get the number of weeks
- Add 1 to account for truncation of a partial week
- Multiply that result by 40 to get the number of hours needed to complete the project
- Close the code editor.
- Open the project properties for the
LBLDURATION project.
- Expand
Micro Focus > Project Settings > COBOL; then select
SQL Settings. Several OpenESQL compiler directives have been set for you. The following table offers a brief description of each:
SQL(DBMAN=ODBC)
|
Uses an ODBC connection
|
SQL(TARGETDB=MSSQLSERVER)
|
Target database is SQL Server
|
SQL(DB=HCODemo)
|
SQL Server connection name is HCODemo
|
SQL(DIALECT=MAINFRAME)
|
HCOSS database syntax conversion is enabled
|
SQL(DBRMLIB)
|
EXEC-SQL commands are extracted and placed in database request module (DBRM)
|
SQL(DATE=USA)
|
Date output is in USA format
|
SQL(INIT)
|
Initiates the database connection
|
SQL(QUALIFIER=TEST)
|
Schema qualifier is TEST
|
SQL(NOCHECK)
|
No SQL compile-time checking performed
|
SQL(BEHAVIOR=OPTIMIZED)
|
Optimizes migration process
|
- Define a Post-Build Event
-
- In the Properties window,
expand
Micro Focus > Build Configurations > Events.
- In the Post build event command line field, type the following command:
DSN SYSTEM(HCODemo) @"LBLDURATION.hcodsn"
This command calls the DSN Bind utility, specifies the SQL database connection to use, and states the location and name of a bind script file.
Eclipse executes this event immediately after building the application, automatically binding the application at that time.
- Click
OK.
Eclipse builds the native application automatically.
- View the Contents of the Bind Script File
-
- From the
COBOL Explorer, open and review the content of
LBLDURATION.hcodsn. This bind script file contains one BIND PLAN command that binds the LBLDURATION member into a plan named LBLDURATION.
- Verify the Results
-
- Using Microsoft SQL Server Management Studio, connect to your SQL Server instance.
- On the Object Explorer, expand
Databases > HCO_Test > Programmability > Stored Procedures to see the stored procedures HCOSS created when you executed your packages and plan.
- Open the stored procedure named
PLN:LBLDURATION.LBLDURATIONconsistency-token$0, where
consistency-token is the value of the generated consistency token.
In this, you see the SQL from your application code. You also see that HCOSS has converted the original DB2 DAYS expression into T-SQL syntax that recreates the same functionality in SQL Server. This is due to having set the SQL(DIALECT=MAINFRAME) directive when you compiled.
Phase 3: Run the Native Application
- From the
COBOL Explorer, open the
LBLDURATION.cbl source file.
- Set a break point on the GO BACK line.
- Click
Run > Debug to start debugging.
- If prompted with the Debug As dialog box, select
COBOL Application; then click
OK.
- When prompted to open the Debug perspective, click
Yes.
- Click
Resume to continue to your breakpoint.
You see from the output that your results show the hours required to complete each project. All output dates are in USA format.
Note: If the output window is not visible, minimize Eclipse to reveal it.
This completes the tutorial.