Bde.DBTables.TQuery.UniDirectional
Delphi
property UniDirectional: Boolean read FUniDirectional write FUniDirectional default False;
C++
__property bool UniDirectional = {read=FUniDirectional, write=FUniDirectional, default=0};
Properties
Type | Visibility | Source | Unit | Parent |
---|---|---|---|---|
property | published | Bde.DBTables.pas Bde.DBTables.hpp |
Bde.DBTables | TQuery |
Description
Determines whether or not Borland Database Engine (BDE) bidirectional cursors are enabled for a query's result set.
Set UniDirectional to control whether or not a BDE cursor can move forward and backward through a result set. By default UniDirectional is false, enabling forward and backward navigation.
Traditionally SQL cursors are unidirectional. They can travel only forward through a dataset. The BDE, however, permits bidirectional travel by caching records. If an application does not need bidirectional access to records in a result set, set UniDirectional to true. When UniDirectional is true, an application requires less memory and performance is improved.
Note: Do not confuse the UniDirectional property, which indicates whether the BDE cursor is unidirectional, with the IsUniDirectional property inherited from TDataSet. IsUniDirectional, which implies additional restrictions such as a lack of buffering, is always false for TQuery.