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property Active default False;


__property Active = {default=0};


Type Visibility Source Unit Parent
property published
Data.SqlExpr TCustomSQLDataSet


Specifies whether or not a dataset is open.

Data.SqlExpr.TCustomSQLDataSet.Active inherits from Data.DB.TDataSet.Active. All content below this line refers to Data.DB.TDataSet.Active.

Specifies whether or not a dataset is open.

Use Active to determine or set whether a dataset is populated with data. When Active is false, the dataset is closed; the dataset cannot read or write data and data-aware controls can not use it to fetch data or post edits. When Active is true, the dataset can be populated with data. It can read data from a database or other source (such as a provider). Depending on the CanModify property, active datasets can post changes.

Setting Active to true:

  1. Generates a BeforeOpen event.
  2. Sets the dataset state to dsBrowse.
  3. Establishes a way to fetch data (typically by opening a cursor).
  4. Generates an AfterOpen event.

If an error occurs while opening the dataset, dataset state is set to dsInactive, and any cursor is closed.

Setting Active to false:

  1. Triggers a BeforeClose event.
  2. Sets the State property to dsInactive.
  3. Closes the cursor.
  4. Triggers an AfterClose event.

An application must set Active to false before changing other properties that affect the status of a database or the controls that display data in an application.

Note: Calling the Open method sets Active to true; calling the Close method sets Active to false.

See Also

Code Examples