How to delete a table if it exists? - vba

Question

I use MS Access macros and queries to build my application. I use some temporary import files, and need to either run a macro, or some VBA, to test if they exist, and then if they do, to delete them.
My table name is "TempImport1"
I've researched this via Google searches and have some VBA that might work. I have cut/pasted VBA code under a button in the past, and it worked, but not this time. How do I put the code into a module or a click sub button?
Function IsTable(sTblName As String) As Boolean
'does table exists and work ?
'note: finding the name in the TableDefs collection is not enough,
' since the backend might be invalid or missing
On Error GoTo TrapError
Dim x
x = DCount("*", sTblName)
IsTable = True
Exit Function
TrapError:
Debug.Print Now, sTblName, Err.Number, Err.Description
IsTable = False
End Function

Answer 1

First you should check whether the table exists and then you should try to close it, if it exists. Then you should set warnings to False, so it does not ask you whether you are sure that you want to delete the table.
In the example below, you delete Table3. The If Not IsNull is checking whether the table exists:
Option Compare Database
Option Explicit
Public Sub DeleteIfExists()
Dim tableName As String
tableName = "Table3"
If Not IsNull(DLookup("Name", "MSysObjects", "Name='" & tableName & "'")) Then
DoCmd.SetWarnings False
DoCmd.Close acTable, tableName, acSaveYes
DoCmd.DeleteObject acTable = acDefault, tableName
Debug.Print "Table" & tableName & "deleted..."
DoCmd.SetWarnings True
End If
End Sub
Pretty much the code should work.

Answer 2

To delete the TempImport1 table if it exists just use the below function.
Function DeleteTables()
If Not IsNull(DLookup("Name", "MSysObjects", "Name='TempImport1' AND Type = 1")) Then
DoCmd.DeleteObject acTable, "TempImport1"
End If
End Function
Once the function has been created, create a macro, add the action run code then type in DeleteTables() in to the Function Name.
You then have a macro to run to delete the table if it exists.

Answer 3

Checking MSysObjects (used in other answers) misreported a table as existing if it was recently deleted. I found the following test more reliable.
Option Compare Database
Option Explicit
Public Sub DeleteIfExists()
Dim tableName As String
tableName = "Table3"
On Error Resume Next
Set td = db.TableDefs(tableName)
If Err.Number <> 0 Then
DoCmd.SetWarnings False
DoCmd.Close acTable, tableName, acSaveYes
DoCmd.DeleteObject acTable = acDefault, tableName
Debug.Print "Table" & tableName & "deleted..."
DoCmd.SetWarnings True
End If
End Sub

Answer 4

Here is the version I created to get rid of import error tables. The Err. Number must be 0 to actually remove table. TRACE is my internal flag.
Public Function RemoveImportErrorTables(Optional strTableBaseName As String = "rngExportDaily_ImportErrors") As Integer
'Purpose:
' Remove ImportError Tables
'In:
' Tables base Name
'Out:
' number of tables flushed
'History:
' Created 2021-12-06 16:10 Anton Sachs; Last modified 2021-12-06 16:15 Anton Sachs
'
Dim intResult As Integer
Dim strTableName As String
Dim dbCur As Database
Dim tdfTableDef As TableDef
Dim intTableIndex As Integer
On Error GoTo RemoveImportErrorTables_Err
Set dbCur = CurrentDb()
For intTableIndex = 0 To 100
If intTableIndex = 0 Then
strTableName = strTableBaseName
Else
strTableName = strTableBaseName & CStr(intTableIndex)
End If
On Error Resume Next
Set tdfTableDef = dbCur.TableDefs(strTableName)
If Err.Number = 0 Then
DoCmd.SetWarnings False
DoCmd.Close acTable, strTableName, acSaveYes
DoCmd.DeleteObject acTable = acDefault, strTableName
DoCmd.SetWarnings True
intResult = intResult + 1
Else
On Error GoTo RemoveImportErrorTables_Err
Exit For
End If
Next intTableIndex
RemoveImportErrorTables_Exit:
RemoveImportErrorTables = intResult
If Not tdfTableDef Is Nothing Then
Set tdfTableDef = Nothing
End If
If Not dbCur Is Nothing Then
Set dbCur = Nothing
End If
Exit Function
RemoveImportErrorTables_Err:
If TRACE = 0 Then TRACE = GetStandard("Trace")
If TRACE <> False Then
Debug.Print "Error " & Err.Number & " " & Err.Description & " in RemoveImportErrorTables"
Err.Clear
If TRACE = CTR±Stop Then
Stop
Resume Next
End If
Else
Err.Clear
Resume Next
End If
RemoveImportErrorTables_Fail:
intResult = False
GoTo RemoveImportErrorTables_Exit
End Function