How To Create an Access Database Through Visual Basic 4.0

• Professional and Enterprise Editions of Microsoft Visual Basic, 16-bit and 32-bit, for Windows, version 4.0

SUMMARY

This article describes how to create an Access database programmatically with a code example. The code is useful if you need a database with a specific number of fields and records for testing purposes.

MORE INFORMATION

An Access database called TEST.MDB is created when you click the command button. In this example, the database contains 55 records with each record containing 40 integer fields. By changing some of the code, you alter the number of records and fields and the contents of the records.

In the Form_Load event, the code checks to see if the database exists. If the database does not exist, a command button is shown on the form. Clicking the command button creates the database.

Code Example

1. Start Visual Basic 4.0. If it is already running, from the File menu, click New Project.

2. Add a command button, data control, and a DBGrid control on Form1. Set the DataSource property of the DBGrid control to the Data control.

3. Copy the following code sample to the Form1 code window:

         Option Explicit
         Dim rs1 As Recordset
         Dim rs2 As Recordset
         Dim db As Database
         Dim td As TableDef
         Dim fl As Field
   

         Private Sub Command1_Click()
            Dim iFields As Integer, iRecords As Integer
   
            ' Create the database.
            Set db = CreateDatabase("C:\test.mdb", dbLangGeneral)
            Set td = db.CreateTableDef("Table1")
   
            'Now that the database is created, add fields to the database
            For iFields = 1 To 5 'The last number can be changed.
               Set fl = td.CreateField("Field " & CStr(iFields), dbInteger)
               td.Fields.Append fl
            Next iFields
   
            db.TableDefs.Append td
   
            ' Now that the database has fields, add records through a
            ' recordset.
            Set rs1 = db.OpenRecordset("Table1", dbOpenTable)
            For iRecords = 1 To 10  ' For each row
               rs1.AddNew           ' add a new record.
   
               For iFields = 1 To 5      ' For each field in the record
                  rs1("Field " & CStr(iFields)) = iFields  ' add a number.
               Next iFields
   
               rs1.Update
            Next iRecords
   
            ' Close both the recordset and database.
            rs1.Close
            db.Close
   
            ' Populate the DBGrid control with the contents of the Recordset.
            Set db = OpenDatabase("C:\test.mdb")
            Set rs1 = db.OpenRecordset("Select * from Table1")
            Set Data1.Recordset = rs1
   
            Command1.Visible = False
         End Sub
   
         Private Sub Form_Load()
            If Dir("C:\test.mdb") = "" Then
               Command1.Caption = "Create Database"
               Command1.Visible = True
            End If
   
         End Sub
   
   

4. Press the F5 key, or click Start on the Run menu to run the program. Click the Command button, and populate the DBGrid control. Note that the file TEST.MDB is also created.