RAD to Database Connection

1
RAD to Database Connection

• Glenn Campbell
• Campbell-g8_at_ulster.ac.uk

2
Learning Outcomes

• After this lesson you will be familiar with
• TclODBC
• Linking RAD application to database
• Creating an ODBC Data Source Name (DSN)
• TCL commands
• Using SQL to query a database

3
TclODBC

• Extension to TCL (Tool Command Language) which
  allows access to databases
• Uses standard ODBC interface
• The Rapid Application Developer (RAD) can be
  configured to link to a database
• We will use MS Access for creating the database

4
Initial Steps

• Before you begin, do the following
• Download and install TclODBC from course website
• Create a database in MS Access called name.mdb
  e.g. student.mdb
• We can now create a link between the database and
  the RAD application

5
Testing TclODBC

• Refer to Exercise 20 of Tutorial 12 for
  information on how to test TclODBC in the CSLUsh
  window.
• When you are satisfied that TclODBC is working,
  you can then create a link between your RAD
  application and the Database.

6
RAD to database connection

• The RAD to database connection is achieved using
  the following steps
• Step 1 Create a link between the RAD and the
  database
• Step 2 Create an ODBC Data Source Name (DSN) for
  your database
• Step 3 Create a database object to open a
  connection to the database
• Step 4 Use SQL to query the database

7
Step 1 RAD database link

• Download TclODBC package into the
• . . . \CSLU\Toolkit\2.0\pkg\tclodbc2.2 directory
• Use the following command to create a link
  between RAD and the database
• package require tclodbc
• This command loads the TclODBC program which
  creates a link between RAD and the database
• This (and any other) TCL command can be inserted
  into the On Exit tab of an Action Object

8
Step 2 Create an ODBC DSN

• Select
• Start Control Panel Administrative Tools
  Data Sources (ODBC) Add
• Now enter required information. For example, in
  this example, enter student as the Data Source
  Name (i.e. the name of the database)
• Remember to select Microsoft Access Driver and
  browse for the database you wish to link to.

9
(No Transcript)
10
Step 3 Create database object

• Use the command database to create a database
  object, db which refers to the DSN created in
  Step 2
• To do this use the following command
• Database db name
• where name is the name of the database, e.g.
  student

11
Step 4 Query the database

• The database can now be queried using SQL
• Again, the code is entered into the Action
  object
• For example
• set getDetails db "Select Name from
  StudentRecords where StudentNumber value "
• where Name and StudentNumber are all fields in
  the StudentRecords table of the student database

12
Access 2007 Considerations

• Note that this presentation is related to MS
  Access 2003
• It does work with MS Access 2007
• But there may be some subtle changes in the way
  tclODBC is used

13
Further Information

• Paul Mc Kevitts course website
• http//www.infm.ulst.ac.uk/paul/com556m2/
• CSLU Toolkit webpage
• http//cslu.cse.ogi.edu/toolkit/
• Email me
• Campbell-g8_at_ulster.ac.uk