NOTE: ODBCDirect workspaces are not supported in Microsoft Access 2013. Use ADO if you want to access external data sources without using the Microsoft Access database engine.
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Gets the next set of records, if any, returned by a multi-part select query in an
OpenRecordset call, and returns a
Boolean value indicating whether one or more additional records are pending (ODBCDirect workspaces only).
Syntax
expression .NextRecordset
expression A variable that represents a Recordset object.
Return value
Boolean
Remarks
In an ODBCDirect workspace, you can open a
Recordset containing more than one select query in the source argument of
OpenRecordset, or the
SQL property of a select query
QueryDef object, as in the following example.
SELECT LastName, FirstName FROM Authors WHERE LastName = 'Smith'; SELECT Title, ISBN FROM Titles WHERE Pub_ID = 9999
The returned Recordset will open with the results of the first query. To obtain the result sets of records from subsequent queries, use the NextRecordset method.
If more records are available (that is, there was another select query in the OpenRecordset call or in the SQL property), the records returned from the next query will be loaded into the Recordset, and NextRecordset will return True, indicating that the records are available. When no more records are available (that is, results of the last select query have been loaded into the Recordset), then NextRecordset will return False, and the Recordset will be empty.
You can also use the
Cancel method to flush the contents of a
Recordset. However,
Cancel also flushes any additional records not yet loaded.
Example
This example uses the NextRecordset method to view the data from a compound SELECT query. The DefaultCursorDriver property must be set to dbUseODBCCursor when executing such queries. The NextRecordset method will return True even if some or all of the SELECT statements return zero records; it will return False only after all the individual SQL clauses have been checked.
Sub NextRecordsetX()
Dim wrkODBC As Workspace
Dim conPubs As Connection
Dim rstTemp As Recordset
Dim intCount As Integer
Dim booNext As Boolean
' Create ODBCDirect Workspace object and open Connection
' object. The DefaultCursorDriver setting is required
' when using compound SQL statements.
Set wrkODBC = CreateWorkspace("", _
"admin", "", dbUseODBC)
wrkODBC.DefaultCursorDriver = dbUseODBCCursor
' Note: The DSN referenced below must be set to
' use Microsoft Windows NT Authentication Mode to
' authorize user access to the Microsoft SQL Server.
Set conPubs = wrkODBC.OpenConnection("Publishers", , , _
"ODBC;DATABASE=pubs;DSN=Publishers")
' Construct compound SELECT statement.
Set rstTemp = conPubs.OpenRecordset("SELECT * " & _
"FROM authors; " & _
"SELECT * FROM stores; " & _
"SELECT * FROM jobs")
' Try printing results from each of the three SELECT
' statements.
booNext = True
intCount = 1
With rstTemp
Do While booNext
Debug.Print "Contents of recordset #" & intCount
Do While Not .EOF
Debug.Print , .Fields(0), .Fields(1)
.MoveNext
Loop
booNext = .NextRecordset
Debug.Print " rstTemp.NextRecordset = " & _
booNext
intCount = intCount + 1
Loop
End With
rstTemp.Close
conPubs.Close
wrkODBC.Close
End Sub
Another way to accomplish the same task would be to create a prepared statement containing the compound SQL statement. The CacheSize property of the QueryDef object must be set to 1, and the Recordset object must be forward-only and read-only.
Sub NextRecordsetX2()
Dim wrkODBC As Workspace
Dim conPubs As Connection
Dim qdfTemp As QueryDef
Dim rstTemp As Recordset
Dim intCount As Integer
Dim booNext As Boolean
' Create ODBCDirect Workspace object and open Connection
' object. The DefaultCursorDriver setting is required
' when using compound SQL statements.
Set wrkODBC = CreateWorkspace("", _
"admin", "", dbUseODBC)
wrkODBC.DefaultCursorDriver = dbUseODBCCursor
' Note: The DSN referenced below must be set to
' use Microsoft Windows NT Authentication Mode to
' authorize user access to the Microsoft SQL Server.
Set conPubs = wrkODBC.OpenConnection("Publishers", , , _
"ODBC;DATABASE=pubs;DSN=Publishers")
' Create a temporary stored procedure with a compound
' SELECT statement.
Set qdfTemp = conPubs.CreateQueryDef("", _
"SELECT * FROM authors; " & _
"SELECT * FROM stores; " & _
"SELECT * FROM jobs")
' Set CacheSize and open Recordset object with arguments
' that will allow access to multiple recordsets.
qdfTemp.CacheSize = 1
Set rstTemp = qdfTemp.OpenRecordset(dbOpenForwardOnly, _
dbReadOnly)
' Try printing results from each of the three SELECT
' statements.
booNext = True
intCount = 1
With rstTemp
Do While booNext
Debug.Print "Contents of recordset #" & intCount
Do While Not .EOF
Debug.Print , .Fields(0), .Fields(1)
.MoveNext
Loop
booNext = .NextRecordset
Debug.Print " rstTemp.NextRecordset = " & _
booNext
intCount = intCount + 1
Loop
End With
rstTemp.Close
qdfTemp.Close
conPubs.Close
wrkODBC.Close
End Sub