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ADO Recordset Object CursorType Property

The type of cursor used in a Recordset object.

CursorType Property Return Values

Sets or returns one of the following CursorTypeEnum values:

Constant

Description

adOpenForwardOnly

Forward-only cursor. Default. Identical to a static cursor except that you can only scroll forward through records. This improves performance in situations when you only need to make a single pass through a recordset.

adOpenKeyset

Keyset cursor. Like a dynamic cursor, except that you can't see records that other users add, although records that other users delete are inaccessible from your recordset. Data changes by other users are still visible.

adOpenDynamic

Dynamic cursor. Additions, changes, and deletions by other users are visible, and all types of movement through the recordset are allowed, except for bookmarks if the provider doesn't support them.

adOpenStatic

Static cursor. A static copy of a set of records that you can use to find data or generate reports. Additions, changes, or deletions by other users are not visible.

CursorType Property Remarks

Use the CursorType property to specify the type of cursor that should be used when opening the Recordset object. The CursorType property is read/write when the recordset is closed and read-only when it is open.

If a provider does not support the requested cursor type, the provider may return another cursor type. The CursorType property will change to match the actual cursor type in use when the recordset object is open. To verify specific functionality of the returned cursor, use the ADO Recordset Object Supports Method. After you close the recordset, the CursorType property reverts to its original setting.

The following chart shows the provider functionality (identified by Supports method constants) required for each cursor type.

CursorType

The Supports method must return True for these constants

adOpenForwardOnly

none

adOpenKeyset

adBookmark, adHoldRecords, adMovePrevious, adResync

adOpenDynamic

adMovePrevious

adOpenStatic

adBookmark, adHoldRecords, adMovePrevious, adResync

Note

Although Supports(adUpdateBatch) may be true for dynamic and forward-only cursors, for batch updates you should use either a keyset or static cursor. Set the ADO Recordset Object LockType Property to adLockBatchOptimistic, and set the CursorLocation property to adUseClient (or its synonym, adUseClientBatch) to enable the Microsoft Client Cursor Engine, which is required for batch updates.

CursorType Property Example

This Visual Basic example demonstrates setting the CursorType and LockType properties before opening a recordset. It also shows the value of the ADO Recordset Object EditMode Property under various conditions. The EditModeOutput function is required for this procedure to run.

Public Sub EditModeX()

Dim cnn1 As ADODB.Connection

Dim rstEmployees As ADODB.Recordset

Dim strCnn As String

` Open recordset with data from Employee table.

Set cnn1 = New ADODB.Connection

strCnn = "driver={SQL Server};server=srv;" & _

"uid=sa;pwd=;database=pubs"

cnn1.Open strCnn

Set rstEmployees = New ADODB.Recordset

Set rstEmployees.ActiveConnection = cnn1

rstEmployees.CursorType = adOpenKeyset

rstEmployees.LockType = adLockBatchOptimistic

rstEmployees.Open "employee", , , , adCmdTable

` Show the EditMode property under different editing

` states.

rstEmployees.AddNew

rstEmployees!emp_id = "T-T55555M"

rstEmployees!fname = "temp_fname"

rstEmployees!lname = "temp_lname"

EditModeOutput "After AddNew:", rstEmployees.EditMode

rstEmployees.UpdateBatch

EditModeOutput "After UpdateBatch:", rstEmployees.EditMode

rstEmployees!fname = "test"

EditModeOutput "After Edit:", rstEmployees.EditMode

rstEmployees.Close

` Delete new record because this is a demonstration.

cnn1.Execute "DELETE FROM employee WHERE emp_id = 'T-T55555M'"

End Sub

Public Function EditModeOutput(strTemp As String, _

intEditMode As Integer)

` Print report based on the value of the EditMode

` property.

Debug.Print strTemp

Debug.Print " EditMode = ";

Select Case intEditMode

Case adEditNone

Debug.Print "adEditNone"

Case adEditInProgress

Debug.Print "adEditInProgress"

Case adEditAdd

Debug.Print "adEditAdd"

End Select

End Function

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