Solved

Check for existence of a field in a Microsoft Access table

Posted on 2012-04-04
6
398 Views
Last Modified: 2012-04-04
I have a vba program that alters a linked table - a new field is added.  Before I create the field, I need to make sure that it doesn't already exist.  Here is the code I have to do the alter:

Public Function Alter_Table()
    Dim db As DAO.Database
    Dim tdf As DAO.TableDef
    Dim fld As DAO.Field
    Dim strSQL As String
   
    On Error GoTo Alter_Table_Exit
   
    Set db = DBEngine.OpenDatabase("C:\Quote Templates\Data Files\Quote Data.mdb")
    Set tdf = db.TableDefs("tbl_Quotes")
   
    Set fld = tdf.CreateField("Freight_PO", dbBoolean)
    fld.DefaultValue = 0
    tdf.Fields.Append fld
    Set fld = Nothing
   
    Set fld = tdf.CreateField("Freight_Amt", dbCurrency)
    fld.DefaultValue = 0
    tdf.Fields.Append fld
    Set fld = Nothing
    Set tdf = Nothing
   
    db.Close
    Set db = Nothing

    Set db = CurrentDb()
    Set tdf = db.TableDefs("tbl_Quotes")
    tdf.RefreshLink

Alter_Table_Exit:
   
    DoCmd.OpenQuery ("qupd_Freight_Amt_0")
     
    Set tdf = Nothing
    db.Close
    Set db = Nothing
    Exit Function
   
End Function
0
Comment
Question by:Marilync1266
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
  • 3
6 Comments
 
LVL 120

Expert Comment

by:Rey Obrero (Capricorn1)
ID: 37807717
Set db = DBEngine.OpenDatabase("C:\Quote Templates\Data Files\Quote Data.mdb")
    Set tdf = db.TableDefs("tbl_Quotes")

'add this codes

For Each fld In tdf.Fields
    If fld.Name = "Freight_PO" Then
        MsgBox "Field exists"
        Exit Function
    End If
Next

'end of codes    to add

Set fld = tdf.CreateField("Freight_PO", dbBoolean)
    fld.DefaultValue = 0
    tdf.Fields.Append fld
    Set fld = Nothing
0
 

Author Comment

by:Marilync1266
ID: 37807794
If it exists - I don't want to display a message, I need to continue in the code to check the next field - Freight_Amt
0
 
LVL 120

Expert Comment

by:Rey Obrero (Capricorn1)
ID: 37807811
ok, how many fields are you going to check?
0
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 

Author Comment

by:Marilync1266
ID: 37807815
Just 2 - freight_po and freight_amt
0
 
LVL 120

Accepted Solution

by:
Rey Obrero (Capricorn1) earned 500 total points
ID: 37807856
Public Function Alter_Table()
    Dim db As DAO.Database
    Dim tdf As DAO.TableDef
    Dim fld As DAO.Field
    Dim strSQL As String
   
    On Error GoTo Alter_Table_Exit
   
    Set db = DBEngine.OpenDatabase("C:\Quote Templates\Data Files\Quote Data.mdb")
    Set tdf = db.TableDefs("tbl_Quotes")
   
   Dim blnFld1 As Boolean, blnFld2 As Boolean
   For Each fld In tdf.Fields
        If fld.Name = "Freight_PO" Then
            blnFld1 = True
        End If
        If fld.Name = "freight_amt" Then
            blnFld2 = True
        End If
   
    Next

   If blnFld1 = False Then
            Set fld = tdf.CreateField("Freight_PO", dbBoolean)
            fld.DefaultValue = 0
            tdf.Fields.Append fld
            Set fld = Nothing
   End If
   
      If blnFld2 = False Then

            Set fld = tdf.CreateField("Freight_Amt", dbCurrency)
            fld.DefaultValue = 0
            tdf.Fields.Append fld
            Set fld = Nothing
            Set tdf = Nothing
   End If
    db.Close
    Set db = Nothing

    Set db = CurrentDb()
    Set tdf = db.TableDefs("tbl_Quotes")
    tdf.RefreshLink

Alter_Table_Exit:
   
    DoCmd.OpenQuery ("qupd_Freight_Amt_0")
     
    Set tdf = Nothing
    db.Close
    Set db = Nothing
    Exit Function
   
End Function
0
 

Author Comment

by:Marilync1266
ID: 37807906
Excellent!  Thanks!
0

Featured Post

Online Training Solution

Drastically shorten your training time with WalkMe's advanced online training solution that Guides your trainees to action. Forget about retraining and skyrocket knowledge retention rates.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Access custom database properties are useful for storing miscellaneous bits of information in a format that persists through database closing and reopening.  This article shows how to create and use them.
This article shows how to get a list of available printers for display in a drop-down list, and then to use the selected printer to print an Access report or a Word document filled with Access data, using different syntax as needed for working with …
In Microsoft Access, learn how to use Dlookup and other domain aggregate functions and one method of specifying a string value within a string. Specify the first argument, which is the expression to be returned: Specify the second argument, which …
The viewer will learn how to simulate a series of sales calls dependent on a single skill level and learn how to simulate a series of sales calls dependent on two skill levels. Simulating Independent Sales Calls: Enter .75 into cell C2 – “skill leve…

628 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question