ASP code: rs.open statement detailed description

'*********************************************************************

'rs.open statement detailed description

'rs.Open [first parameter], [second parameter], [third parameter], [fourth parameter], (fifth parameter)

'rs.Open [data table name or SQL directive], [specify the current connection], [indicate CursorType], [indicate LockType], (adCmdTable/adCmdText)

'-------------------------------------------------------------

'The first parameter

'It can be a table name or a SQL statement

'-------------------------------------------------------------

'The second parameter

'Specify the current connection.

'-------------------------------------------------------------

'The third parameter

'Indicates CursorType, CursorType indicates what cursor type will be started with,

'Including adOpenForwardOnly, adOpenKeyset, adOpenDynamic and adOpenStatic,

'The following are the descriptions:

'The third parameter constant constant value description

' adOpenForwardOnly 0 Default value, start a cursor that can only move forward (Forward Only).

' adOpenKeyset 1 Start a cursor of Keyset type.

' adOpenDynamic 2 Start a Dynamic type cursor.

' adOpenStatic 3 Starts a Static type cursor.

'-------------------------------------------------------------

'The above cursor types will directly affect all properties and methods of the Recordset object. The following list explains the difference between them.

'Recordset property adOpenForwardOnly(0) adOpenKeyset(1) adOpenDynamic(2) adOpenStatic(3)

'AbsolutePage does not support readable, writeable, readable, writeable

'AbsolutePosition does not support readable, writeable, readable, writeable

'ActiveConnection Readable, writeable, readable, writeable, readable, writeable, readable, writeable

'BOF Read only Read only Read only Read only Read only

'Bookmark does not support readable, writeable, readable, writeable

'CacheSize Readable, Writeable, Readable, Writeable, Readable, Writeable

'CursorLocation Readable, writeable, readable, writeable, readable, writeable, readable, writeable

'CursorType Readable, writeable, readable, writeable, readable, writeable, readable, writeable

'EditMode Read-only Read-only Read-only Read-only

'EOF Read-only Read-only Read-only Read-only

'Filter readable, writeable, readable, writeable, readable, writeable, readable, writeable

'LockType Readable, writeable, readable, writeable, readable, writeable, readable, writeable

'MarshalOptions Readable, writeable, readable, writeable, readable, writeable, readable, writeable

'MaxRecords Readable, Writable, Readable, Writable, Readable, Writable

'PageCount does not support read-only read-only

'PageSize Readable, Writable, Readable, Writable, Readable, Writable

'RecordCount does not support read-only read-only

'Source can read, write, read, write, read, write, read, write

'State Read-only Read-only Read-only Read-only

'Status Read-only Read-only Read-only Read-only

'AddNew Support Support Support Support

'CancelBatch Support Support Support Support

'CancelUpdate Support Support Support Support

'Clone is not supported or supported

'Close Support Support Support Support

'Delete Support Support Support Support

'GetRows Support Support Support Support

'Move does not support support support support

'MoveFirst Support Support Support Support

'MoveLast does not support support support support

'MoveNext Support Support Support Support

'MovePrevious does not support support support support

'Open Support Support Support Support

'Requery Support Support Support Support

'Resync does not support support support support

'Supports Support Support Support

'Update Support Support Support Support

'UpdateBatch Support Support Support Support

'NextRecordset Support Support Support Support

The 'NextRecordset method does not work with Microsoft Access databases.

'--------------------------------------------------------------------

'The fourth parameter

'Indicates LockType to determine the lock (concurrency) type that the provider should use when opening Recordset.

'The following are the descriptions:

'The fourth parameter constant value description

' adLockReadOnly 1 default value, the Recordset object is started read-only, and the AddNew, Update, Delete and other methods cannot be run

' adLockPrssimistic 2 When the data source is being updated, the system temporarily locks other users' actions to maintain data consistency.

' adLockOptimistic 3 When the data source is being updated, the system will not lock other users' actions. Other users can add, delete and modify the data.

' adLockBatchOptimistic 4 When the data source is being updated, other users must change the CursorLocation property to adUdeClientBatch to add, delete, and modify the data

'-------------------------------------------------------------------

'The fifth parameter

'Related to the first parameter,

'If the first parameter is the table name, the fifth parameter uses adCmdTable.

'If the first parameter is a SQL statement, the parameter is adCmdText

'The fifth parameter can be omitted and not filled in

'*********************************************************************************

(Note: The code format is not aligned in this editor, if the COPY code is in the DW code view, the code format will be aligned)