Copying tabledefs between databases
Quote:
> Can anyone help me with a problem I have creating copies of a datebase.
> The application I am developing (VB4.0 32 Prof/Jet 3.0) has a seperate
> database for each project, that need to be created 'on the fly'. The
> tables required are stored in a central .mdb file and I need to copy
> them into each project database. I suppose I could create them anew each
> time but this seems like the long way round.
> I hope someone can help.
Do you need to copy just the structures, or the structure and the
data? What about indexes or relationships between tables? You
could open up both databases (RTFM CreateDatabase if you need to
create new MDB's dynamically) and copy the TableDefs using
CreateTableDef, CreateField, CreateIndex, and CreateRelation and
then copy over the various properties. If you need to copy the
data too, I'd do this before copying the indexes and
relationships. You might run into trouble with counters, but I
think VB 3.0 at least supports overriding a counter's default
value. Anyway, here's some untested code off the top of my head
to copy data from one Recordset to another:
Sub CopyRecordset (Src As Recordset, Dst As Recordset)
Dim MaxFieldID As Integer: MaxFieldID = Src.Fields.Count - 1
If (Src.RecordCount > 0) Then Src.MoveFirst
While (Src.EOF = False)
Dst.AddNew
Dim f As Integer: For f = 0 to MaxFieldID
Select Case Dst(f).Type
Case DB_MEMO, DB_LONGBINARY:
Dim FL As Long: FL = Src(f).FieldSize
Dim i As Long: i = 0
While (i < FL)
Dim buf As String
If (FL - i >= 4096) Then
buf = Src(f).GetChunk(i, 4096)
Else
buf = Src(f).GetChunk(i, FL - i)
End If
Dst(f).AppendChunk buf
i = i + Len(buf)
Wend
Case Else:
Dst(f) = Src(f)
End Select
Next f
Dst.Update
Wend
End Sub
--
WARNING: I cannot be held responsible for the above They're coming to
because my cats have apparently learned to type. take me away, ha ha!
