Using ADO in VBA to connect to PostgreSQL

Question

I am having trouble finding clear and reliable examples of connecting to a PostgreSQL database from Excel using VBA ADO. Admittedly, I am new to VBA and most examples and tutori

Answer 1

Set cmd = New ADODB.Command cmd.ActiveConnection = cnn

Answer 2

Not sure about the details of the actual DB connection, but there is a simple although common mistake with your statement: you need to use 'set' when working with objects:

set cmd.ActiveConnection = cnn

Answer 3

In the original Code, "PostgreSQL35W" is a DSN name which included the default host and port. When you changed to "PostgreSQL Unicode", it is a driver and your connection string is lacking the value for the port. Remember to access PostgreSQL directly from driver, you need at least 5 parameters:

• host
• port
• userid
• password
• database

If you are using DSN, some parameters may be defined as default.

Answer 4

I wan't using a DSN as I am using an ODBC driver as opposed to OLE DB. By referencing a DSN, the above code works with very few changes.

See this question for how I found the answer once I began to suspect OLE DB/ODBC to the issue. Does ADO work with ODBC drivers or only OLE DB providers?

New Code here:

Sub GetCustomers()
Dim oConn As New ADODB.connection
Dim cmd As New ADODB.Command
' Connection Parameters
Dim strUsername As String
Dim strPassword As String
Dim strServerAddress As String
Dim strDatabase As String
' User:
strUsername = Sheets("CONFIG").Range("B4").Value
' Password:
strPassword = Sheets("CONFIG").Range("B5").Value
' Server Address:
strServerAddress = Sheets("CONFIG").Range("B6").Value
' Database
strDatabase = Sheets("CONFIG").Range("B3").Value


oConn.Open "DSN=my_system_dsn;" & _
    "Database=" & strDatabase & ";" & _
    "Uid=" & strUsername & ";" & _
    "Pwd=" & strPassword

Set xlSheet = Sheets("CUSTOMERS")
xlSheet.Activate
Range("A3").Activate
Selection.CurrentRegion.Select
Selection.ClearContents
Range("A1").Select

Dim strSQL As String
strSQL = "SELECT * FROM customers"

cmd.CommandType = ADODB.CommandTypeEnum.adCmdText
cmd.ActiveConnection = oConn
cmd.CommandText = strSQL

Set rs = New ADODB.Recordset
Set rs = cmd.Execute

For i = 1 To rs.Fields.Count
    ActiveSheet.Cells(3, i).Value = rs.Fields(i - 1).Name
Next i

xlSheet.Range(xlSheet.Cells(3, 1), _
    xlSheet.Cells(3, rs.Fields.Count)).Font.Bold = True

ActiveSheet.Range("A4").CopyFromRecordset rs

xlSheet.Select
Range("A3").Select
Selection.CurrentRegion.Select
Selection.Columns.AutoFit
Range("A1").Select

rs.Close
oConn.Close

Set cmd = Nothing
Set param = Nothing
Set rs = Nothing
Set cnn = Nothing
Set xlSheet = Nothing
End Sub

The System DSN is configured to use the PostgreSQL Unicode driver. I chose not to use OLE DB even though there is a provider available. If you look at PGFoundry, you will see it has many problems and has not been updated in several years.