Attributes, methods, events, and constants of three ADO objects (4)

 

Constant

Constants used by the AbsolutePage attribute

Constant meaning
The adPosUnknown data provider does not support pages. The Recordset is empty, or the data provider cannot determine the page number.
The adPosBOF record pointer is located at the beginning of the file (the BOF attribute value is True)
The adPosEOF record pointer is located at the end of the file (the EOF attribute value is True)

Constant used by the CursorLocation attribute

Constant meaning
AdUseClient uses the cursor provided by the client cursor library. ADODB. Recordset requires client cursor
AdUseServer uses the cursor provided by the data source, usually (but not absolute) located on the server (default)

Constant used by the CursorType attribute

Constant meaning
AdOpenForwardonly provides one-way moving cursor and read-only Recordset (default)
AdOpenDynamic provides a scroll cursor to display changes made by other users to Recordset (including adding new records)
AdOpenKeyset provides a scroll cursor that only hides changes made by other users, similar to DAO. Recordset of dynaset type.
AdOpenStatic provides a scroll cursor on the Recordset static copy, similar to DAO. Recordset of the snapshot type, but has the updatable feature

Constant used by the EditMode attribute

Constant meaning
No ongoing editing operation in adEditNone (default)
AdEditAdd temporarily adds a record, but has not been stored in the database table
The data in the current record of adEditInProgress has been changed but has not been saved to the database table.

Constant used by the Filter attribute

Constant meaning
AdFilterNone removes the existing Filter and displays all records in the Recordset (equivalent to setting the Filter attribute to a null string, default value)
AdfilterAffectedRecords only displays the records affected by the last execution of the CancelBatch, Delete, Resync, or UpdateBatch method.
AdFilterFetchedRecords only records in the current Cache. The number of records is determined by CacheSize.
AdFilterPendingRecords only displays records modified but not processed by the data source (only applicable to batch update mode)

The constant used by the LockType attribute

Constant meaning
AdLockRecordOnly specifies read-only access (default)
AdLockBatchOptimistic uses the batch update mode instead of the default instant update mode.
AdLockOptimistic use optimistic locks (logging or pages are locked only during update)
AdLockPessimistic use pessimistic locks (records or pages are locked during editing or updating)

State constant

Constant meaning
AdStateClosed Connection (or other objects) is disabled (default)
The status of adStateConnecting connecting to the data source
The Execute method of the adStateExecuting Connection or Command object has been called.
AdStateFetching returns row to Recordset object
AdStateOpen Connection (or other objects) is open (active)

Constant used by the Status attribute (only applicable to Batch or Bulk Recordset operations)

Constant meaning
AdRecOK updated
AdRecNew added successfully
AdRecModified modified successfully
AdRecDeleted is successfully deleted.
AdRecUnmodified not modified
AdRecInvalid not saved: the Bookmark attribute is invalid.
AdRecMultipleChanges not saved: saving will affect other records
AdRecPendingChanges is not saved: The record references a waiting insert operation.
AdRecCanceled not saved: Operation canceled
AdRecCantRelease not saved: The existing record value cannot be saved.
AdRecConcurrencyViolation not saved: Optimistic Concurrency lock has a problem
AdRecIntegrityViolation not saved: The operation will affect the consistency.
AdRecMaxChangesExceeded not saved: too many pending changes
AdRecObjectOpen not saved: A conflict occurs when the storage object is opened.
AdRecOutofMemory not saved: insufficient memory
AdRecPermissionDenied not saved: insufficient User Permissions
AdRecSchemaViolation not saved: The record structure does not comply with the database definition
AdRecDBDeleted not saved or deleted: the record has been deleted

Constant used by the lngAffectRecords Parameter

Meaning of constant of Command type
AdAffectAll includes all records of the Recordset object. The records filtered and hidden by the Filter attribute are also included (default)
AdAffectCurrent only includes the current record
AdAffectGroup only includes records that meet the current Filter condition.

The Bookmark constant used by the varStart Parameter

Constant meaning
AdBookmarkCurrent starts from the current record (default)
AdBookmarkFirst starts from the first record
AdBookmarkLast starts from the last record

 

Constants used by the Supports Method

Constant meaning
AdAddNew call AddNew Method
Set adApproxPosition and obtain the attribute values of Absoluteposition and AbsolutePage.
Set and obtain the Bookmark Attribute Value
AdDelete calls the Delete Method
AdHoldRecords obtains another record or changes the position of the retrieved record pointer, but does not submit unconfirmed changes.
AdMovePrevious calls the GetRows, Move, MoveFirst, and MovePrevious methods (indicating a bidirectional scroll cursor)
AdResync calls the Resync Method
AdUpdate calls the Update Method
AdUpdateBatch calls the UpdateBatch and CancelBatch Methods

 

Constants used by the adReason Parameter

Constant meaning
AdRsnAddNew calls the AddNew method.
AdRsnClose calls the Close method.
AdRsnDelete calls the Delete method.
AdRsnFirstChange modified the record field value for the first time.
AdRsnMove calls the Move method.
AdRsnMoveFirst calls the MoveFirst method.
AdRsnMoveLast calls the MoveLast method.
AdRsnMovePrevious calls the MovePrevious method.
AdRsnRequery calls the Requery Method
AdRsnResync calls the Resync Method
The AdRsnUndoAddNew operation is canceled by the user.
The AdRsnUndoDelete operation is canceled by the user.
The AdRsnUndoUpdate operation is canceled by the user.
AdRsnUpdate calls the Update method.