Find PrimaryKey in Recordset from ODBC

[mini0623]

Set recordSet = New ADODB.recordSet
recordSet.Open SQL***, con, adOpenForwardOnly, adLockReadOnly, -1

I have got data from above SQL.
And I want to know which field is PrimaryKey at the table.

I tried to get that as below but got a error 91

[zmbd]

looks like you are missing some information in your post.

With a dao I would use:
CurrentDb.TableDefs("MyTable").Indexes("PrimaryKey ").Fields

you might find Allen's code helpful ShowSchema()

You might also find the adOpenForwardOnly to give you some issues...

[mbizup]

This will return the name of AutoIncrement fields in an ADODB recordset -- useful if your PK is set to auto increment:

 Dim rs As ADODB.Recordset
 Set rs = New ADODB.Recordset
 Dim fld As ADODB.Field
 rs.Open "SELECT * FROM tblYourTable", CurrentProject.Connection, adOpenForwardOnly, adLockReadOnly, -1
 For Each fld In rs.Fields
    If fld.Properties("ISAUTOINCREMENT") = True Then Debug.Print fld.Name
 Next fld