Recordset Object (DAO)
A Recordset object represents the records in a base table or the records that result from running a query.
Remarks
You use Recordset objects to manipulate data in a database at the record level. When you use DAO objects, you manipulate data almost entirely using Recordset objects. All Recordset objects are constructed using records (rows) and fields (columns). There are five types of Recordset objects:
Table-type Recordset— representation in code of a base table that you can use to add, change, or delete records from a single database table (Microsoft Access workspaces only).
Dynaset-type Recordset— the result of a query that can have updatable records. A dynaset-type Recordset object is a dynamic set of records that you can use to add, change, or delete records from an underlying database table or tables. A dynaset-type Recordset object can contain fields from one or more tables in a database. This type corresponds to an ODBC keyset cursor.
Snapshot-type Recordset— a static copy of a set of records that you can use to find data or generate reports. A snapshot-type Recordset object can contain fields from one or more tables in a database but can't be updated. This type corresponds to an ODBC static cursor.
Forward-only-type Recordset— identical to a snapshot except that no cursor is provided. You can only scroll forward through records. This improves performance in situations where you only need to make a single pass through a result set. This type corresponds to an ODBC forward-only cursor.
Dynamic-type Recordset— a query result set from one or more base tables in which you can add, change, or delete records from a row-returning query. Further, records other users add, delete, or edit in the base tables also appear in your Recordset. This type corresponds to an ODBC dynamic cursor (ODBCDirect workspaces only).
Note
ODBCDirect workspaces are not supported in Microsoft Access 2010. Use ADO if you want to access external data sources without using the Microsoft Access database engine.
You can choose the type of Recordset object you want to create using the type argument of the OpenRecordset method.
In a Microsoft Access workspace, if you don't specify a type, DAO attempts to create the type of Recordset with the most functionality available, starting with table. If this type isn't available, DAO attempts a dynaset, then a snapshot, and finally a forward-only type Recordset object.
In an ODBCDirect workspace, if you don't specify a type, DAO attempts to create the type of Recordset with the fastest query response, starting with forward-only. If this type isn't available, DAO attempts a snapshot, then a dynaset, and finally a dynamic- type Recordset object.
When creating a Recordset object using a non-linked TableDef object in a Microsoft Access workspace, table-type Recordset objects are created. Only dynaset-type or snapshot-type Recordset objects can be created with linked tables or tables in Microsoft Access database engine-connected ODBC databases.
A new Recordset object is automatically added to the Recordsets collection when you open the object, and is automatically removed when you close it.
Note
If you use variables to represent a Recordset object and the Database object that contains the Recordset, make sure the variables have the same scope, or lifetime. For example, if you declare a public variable that represents a Recordset object, make sure the variable that represents the Database containing the Recordset is also public, or is declared in a Sub or Function procedure using the Static keyword.
You can create as many Recordset object variables as needed. Different Recordset objects can access the same tables, queries, and fields without conflicting.
Dynaset–, snapshot–, and forward–only–type Recordset objects are stored in local memory. If there isn't enough space in local memory to store the data, the Microsoft Access database engine saves the additional data to TEMP disk space. If this space is exhausted, a trappable error occurs.
The default collection of a Recordset object is the Fields collection, and the default property of a Field object is the Value property. Use these defaults to simplify your code.
When you create a Recordset object, the current record is positioned to the first record if there are any records. If there are no records, the RecordCount property setting is 0, and the BOF and EOF property settings are True.
You can use the MoveNext, MovePrevious, MoveFirst, and MoveLast methods to reposition the current record. Forward–only–type Recordset objects support only the MoveNext method. When using the Move methods to visit each record (or "walk" through the Recordset), you can use the BOF and EOF properties to check for the beginning or end of the Recordset object.
With dynaset- and snapshot-type Recordset objects in a Microsoft Access workspace, you can also use the Find methods, such as FindFirst, to locate a specific record based on criteria. If the record isn't found, the NoMatch property is set to True. For table-type Recordset objects, you can scan records using the Seek method.
The Type property indicates the type of Recordset object created, and the Updatable property indicates whether you can change the object's records.
Information about the structure of a base table, such as the names and data types of each Field object and any Index objects, is stored in a TableDef object.
To refer to a Recordset object in a collection by its ordinal number or by its Name property setting, use any of the following syntax forms:
Recordsets(0)
Recordsets("name")
Recordsets![name]
Note
You can open a Recordset object from the same data source or database more than once, creating duplicate names in the Recordsets collection. You should assign Recordset objects to object variables and refer to them by variable name.
Example
This example demonstrates Recordset objects and the Recordsets collection by opening four different types of Recordsets, enumerating the Recordsets collection of the current Database, and enumerating the Properties collection of each Recordset.
Sub RecordsetX()
Dim dbsNorthwind As Database
Dim rstTable As Recordset
Dim rstDynaset As Recordset
Dim rstSnapshot As Recordset
Dim rstForwardOnly As Recordset
Dim rstLoop As Recordset
Dim prpLoop As Property
Set dbsNorthwind = OpenDatabase("Northwind.mdb")
With dbsNorthwind
' Open one of each type of Recordset object.
Set rstTable = .OpenRecordset("Categories", _
dbOpenTable)
Set rstDynaset = .OpenRecordset("Employees", _
dbOpenDynaset)
Set rstSnapshot = .OpenRecordset("Shippers", _
dbOpenSnapshot)
Set rstForwardOnly = .OpenRecordset _
("Employees", dbOpenForwardOnly)
Debug.Print "Recordsets in Recordsets " & _
"collection of dbsNorthwind"
' Enumerate Recordsets collection.
For Each rstLoop In .Recordsets
With rstLoop
Debug.Print " " & .Name
' Enumerate Properties collection of each
' Recordset object. Trap for any
' properties whose values are invalid in
' this context.
For Each prpLoop In .Properties
On Error Resume Next
If prpLoop <> "" Then Debug.Print _
" " & prpLoop.Name & _
" = " & prpLoop
On Error GoTo 0
Next prpLoop
End With
Next rstLoop
rstTable.Close
rstDynaset.Close
rstSnapshot.Close
rstForwardOnly.Close
.Close
End With
End Sub
This example uses the OpenRecordset method to open five different Recordset objects and display their contents. The OpenRecordsetOutput procedure is required for this procedure to run.
Sub OpenRecordsetX()
Dim wrkAcc As Workspace
Dim wrkODBC As Workspace
Dim dbsNorthwind As Database
Dim conPubs As Connection
Dim rstTemp As Recordset
Dim rstTemp2 As Recordset
' Open Microsoft Access and ODBCDirect workspaces, Microsoft
' Access database, and ODBCDirect connection.
Set wrkAcc = CreateWorkspace("", "admin", "", dbUseJet)
Set wrkODBC = CreateWorkspace("", "admin", "", dbUseODBC)
Set dbsNorthwind = wrkAcc.OpenDatabase("Northwind.mdb")
' 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("", , , _
"ODBC;DATABASE=pubs;DSN=Publishers")
' Open five different Recordset objects and display the
' contents of each.
Debug.Print "Opening forward-only-type recordset " & _
"where the source is a QueryDef object..."
Set rstTemp = dbsNorthwind.OpenRecordset( _
"Ten Most Expensive Products", dbOpenForwardOnly)
OpenRecordsetOutput rstTemp
Debug.Print "Opening read-only dynaset-type " & _
"recordset where the source is an SQL statement..."
Set rstTemp = dbsNorthwind.OpenRecordset( _
"SELECT * FROM Employees", dbOpenDynaset, dbReadOnly)
OpenRecordsetOutput rstTemp
' Use the Filter property to retrieve only certain
' records with the next OpenRecordset call.
Debug.Print "Opening recordset from existing " & _
"Recordset object to filter records..."
rstTemp.Filter = "LastName >= 'M'"
Set rstTemp2 = rstTemp.OpenRecordset()
OpenRecordsetOutput rstTemp2
Debug.Print "Opening dynamic-type recordset from " & _
"an ODBC connection..."
Set rstTemp = conPubs.OpenRecordset( _
"SELECT * FROM stores", dbOpenDynamic)
OpenRecordsetOutput rstTemp
' Use the StillExecuting property to determine when the
' Recordset is ready for manipulation.
Debug.Print "Opening snapshot-type recordset based " & _
"on asynchronous query to ODBC connection..."
Set rstTemp = conPubs.OpenRecordset("publishers", _
dbOpenSnapshot, dbRunAsync)
Do While rstTemp.StillExecuting
Debug.Print " [still executing...]"
Loop
OpenRecordsetOutput rstTemp
rstTemp.Close
dbsNorthwind.Close
conPubs.Close
wrkAcc.Close
wrkODBC.Close
End Sub
Sub OpenRecordsetOutput(rstOutput As Recordset)
' Enumerate the specified Recordset object.
With rstOutput
Do While Not .EOF
Debug.Print , .Fields(0), .Fields(1)
.MoveNext
Loop
End With
End Sub
This example opens a dynamic-type Recordset object and enumerates its records.
Sub dbOpenDynamicX()
Dim wrkMain As Workspace
Dim conMain As Connection
Dim qdfTemp As QueryDef
Dim rstTemp As Recordset
Dim strSQL As String
Dim intLoop As Integer
' Create ODBC workspace and open connection to
' SQL Server database.
Set wrkMain = CreateWorkspace("ODBCWorkspace", _
"admin", "", dbUseODBC)
' Note: The DSN referenced below must be configured to
' use Microsoft Windows NT Authentication Mode to
' authorize user access to the Microsoft SQL Server.
Set conMain = wrkMain.OpenConnection("Publishers", _
dbDriverNoPrompt, False, _
"ODBC;DATABASE=pubs;DSN=Publishers")
' Open dynamic-type recordset.
Set rstTemp = _
conMain.OpenRecordset("authors", _
dbOpenDynamic)
With rstTemp
Debug.Print "Dynamic-type recordset: " & .Name
' Enumerate records.
Do While Not .EOF
Debug.Print " " & !au_lname & ", " & _
!au_fname
.MoveNext
Loop
.Close
End With
conMain.Close
wrkMain.Close
End Sub
This example opens a dynaset-type Recordset and shows the extent to which its fields are updatable.
Sub dbOpenDynasetX()
Dim dbsNorthwind As Database
Dim rstInvoices As Recordset
Dim fldLoop As Field
Set dbsNorthwind = OpenDatabase("Northwind.mdb")
Set rstInvoices = _
dbsNorthwind.OpenRecordset("Invoices", dbOpenDynaset)
With rstInvoices
Debug.Print "Dynaset-type recordset: " & .Name
If .Updatable Then
Debug.Print " Updatable fields:"
' Enumerate Fields collection of dynaset-type
' Recordset object, print only updatable
' fields.
For Each fldLoop In .Fields
If fldLoop.DataUpdatable Then
Debug.Print " " & fldLoop.Name
End If
Next fldLoop
End If
.Close
End With
dbsNorthwind.Close
End Sub
This example opens a forward-only-type Recordset, demonstrates its read-only characteristics, and steps through the Recordset with the MoveNext method.
Sub dbOpenForwardOnlyX()
Dim dbsNorthwind As Database
Dim rstEmployees As Recordset
Dim fldLoop As Field
Set dbsNorthwind = OpenDatabase("Northwind.mdb")
' Open a forward-only-type Recordset object. Only the
' MoveNext and Move methods may be used to navigate
' through the recordset.
Set rstEmployees = _
dbsNorthwind.OpenRecordset("Employees", _
dbOpenForwardOnly)
With rstEmployees
Debug.Print "Forward-only-type recordset: " & _
.Name & ", Updatable = " & .Updatable
Debug.Print " Field - DataUpdatable"
' Enumerate Fields collection, printing the Name and
' DataUpdatable properties of each Field object.
For Each fldLoop In .Fields
Debug.Print " " & _
fldLoop.Name & " - " & fldLoop.DataUpdatable
Next fldLoop
Debug.Print " Data"
' Enumerate the recordset.
Do While Not .EOF
Debug.Print " " & !FirstName & " " & _
!LastName
.MoveNext
Loop
.Close
End With
dbsNorthwind.Close
End Sub
This example opens a snapshot-type Recordset and demonstrates its read-only characteristics.
Sub dbOpenSnapshotX()
Dim dbsNorthwind As Database
Dim rstEmployees As Recordset
Dim prpLoop As Property
Set dbsNorthwind = OpenDatabase("Northwind.mdb")
Set rstEmployees = _
dbsNorthwind.OpenRecordset("Employees", _
dbOpenSnapshot)
With rstEmployees
Debug.Print "Snapshot-type recordset: " & _
.Name
' Enumerate the Properties collection of the
' snapshot-type Recordset object, trapping for
' any properties whose values are invalid in
' this context.
For Each prpLoop In .Properties
On Error Resume Next
Debug.Print " " & _
prpLoop.Name & " = " & prpLoop
On Error Goto 0
Next prpLoop
.Close
End With
dbsNorthwind.Close
End Sub
This example opens a table-type Recordset, sets its Index property, and enumerates its records.
Sub dbOpenTableX()
Dim dbsNorthwind As Database
Dim rstEmployees As Recordset
Set dbsNorthwind = OpenDatabase("Northwind.mdb")
' dbOpenTable is default.
Set rstEmployees = _
dbsNorthwind.OpenRecordset("Employees")
With rstEmployees
Debug.Print "Table-type recordset: " & .Name
' Use predefined index.
.Index = "LastName"
Debug.Print " Index = " & .Index
' Enumerate records.
Do While Not .EOF
Debug.Print " " & !LastName & ", " & _
!FirstName
.MoveNext
Loop
.Close
End With
dbsNorthwind.Close
End Sub
The following example shows how to use the Seek method to find a record in a linked table.
Sample code provided by: .jpg "Access 2010 Programmers Reference book cover")
The Microsoft Access 2010 Programmer’s Reference | About the Contributors
Sub TestSeek()
' Get the path to the external database that contains
' the tblCustomers table we're going to search.
Dim strMyExternalDatabase
Dim dbs As DAO.Database
Dim dbsExt As DAO.Database
Dim rst As DAO.Recordset
Dim tdf As DAO.TableDef
Set dbs = CurrentDb()
Set tdf = dbs.TableDefs("tblCustomers")
strMyExternalDatabase = Mid(tdf.Connect, 11)
'Open the database that contains the table that is linked
Set dbsExt = OpenDatabase(strMyExternalDatabase)
'Open a table-type recordset against the external table
Set rst = dbsExt.OpenRecordset("tblCustomers", dbOpenTable)
'Specify which index to search on
rst.Index = "PrimaryKey"
'Specify the criteria
rst.Seek "=", 123
'Check the result
If rst.NoMatch Then
MsgBox "Record not found."
Else
MsgBox "Customer name: " & rst!CustName
End If
rst.Close
dbs.Close
dbsExt.Close
Set rst = Nothing
Set tdf = Nothing
Set dbs = Nothing
End Sub
The following example shows how to open a Recordset that is based on a parameter query.
Dim dbs As DAO.Database
Dim qdf As DAO.QueryDef
Dim rst As DAO.Recordset
Set dbs = CurrentDb
'Get the parameter query
Set qfd = dbs.QueryDefs("qryMyParameterQuery")
'Supply the parameter value
qdf.Parameters("EnterStartDate") = Date
qdf.Parameters("EnterEndDate") = Date + 7
'Open a Recordset based on the parameter query
Set rst = qdf.OpenRecordset()
The following example shows how to open a Recordset based on a table or a query.
Dim dbs As DAO.Database
Dim rsTable As DAO.Recordset
Dim rsQuery As DAO.Recordset
Set dbs = CurrentDb
'Open a table-type Recordset
Set rsTable = dbs.OpenRecordset("Table1", dbOpenTable)
'Open a dynaset-type Recordset using a saved query
Set rsQuery = dbs.OpenRecordset("qryMyQuery", dbOpenDynaset)
The following example shows how to open a Recordset based on a Structured Query Language (SQL) statement.
Dim dbs As DAO.Database
Dim rsSQL As DAO.Recordset
Dim strSQL As String
Set dbs = CurrentDb
'Open a snapshot-type Recordset based on an SQL statement
strSQL = "SELECT * FROM Table1 WHERE Field2 = 33"
Set rsSQL = dbs.OpenRecordset(strSQL, dbOpenSnapshot)
The following example shows how to use the FindFirst and FindNext methods to find a record in a Recordset.
Sub FindOrgName()
Dim dbs As DAO.Database
Dim rst As DAO.Recordset
'Get the database and Recordset
Set dbs = CurrentDb
Set rst = dbs.OpenRecordset("tblCustomers")
'Search for the first matching record
rst.FindFirst "[OrgName] LIKE '*parts*'"
'Check the result
If rst.NoMatch Then
MsgBox "Record not found."
GotTo Cleanup
Else
Do While Not rst.NoMatch
MsgBox "Customer name: " & rst!CustName
rst.FindNext "[OrgName] LIKE '*parts*'"
Loop
'Search for the next matching record
rst.FindNext "[OrgName] LIKE '*parts*'"
End If
Cleanup:
rst.Close
Set rst = Nothing
Set dbs = Nothing
End Sub
The following example shows how to copy the results of a query to a worksheet in a new Microsoft Excel workbook.
Public Sub CopyDataFromQuery( _
xlApp As Excel.Application, _
strQueryName As String)
' If the xlApp object exists
If Not xlApp Is Nothing Then
' If the Workbook exists
If xlApp.Workbooks.Count = 1 Then
' Create Recrodset Object from the Query
Dim rsQuery As DAO.Recordset
Set rsQuery = Application.CurrentDb.OpenRecordset(strQueryName)
' Get the Cells object
Dim Cells As Object
Set Cells = xlApp.Workbooks(1).ActiveSheet.Cells
' Copy the Data from the Query into the Sheet
Cells.CopyFromRecordset rsQuery
End If
End If
End Sub
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