Changes to database components

For the communication with the database, a set of Isah-specific database components is present. If you use scripts to write customizations for Isah applications, you use these components to establish connections, to execute queries and stored procedures, and to retrieve datasets.

Because of the transition from Sybase to MS SQL, the database components have been replaced. The new set consists of a Connection component, a number of basic DataSet components, a ClientDataSet component, and a number of Update objects. The basic DataSet components are now unidirectional. Only a unidirectional cursor can be opened. Also, the basic datasets no longer have an internal buffer that can hold multiple records.

The basic dataset components can still be used to retrieve data. Please take note of the following:

Only 'First' and 'Next' can be used to navigate.
The data retrieved cannot be changed.
It is not possible to apply a filter to the dataset.
The dataset cannot be linked to a grid.
Lookup fields are not supported when unidirectional datasets are used.

To be able to change the data retrieved, you must now use a combination of a ClientDataSet component and an Update object.

Previous releases	Isah 4.5.2	Description
TxConnextion	TIsahConnection	This component is responsible for the connection with the database. Just like TxConnextion, the component is not visible among the components of the ScriptIDE.
TxQuery	TIsahQuery	Basic dataset component for retrieving data using a SQL command.
TxStoredProc	TIsahStoredProc	Basic dataset component for retrieving data using a stored procedure.
TxUpdateSQL	This component has been removed from this release.	The basic datasets are now unidirectional, and editing is no longer supported. A basic dataset using a TxUpdateSQL component must be replaced by a TIsahCDSQuery component. A TIsahCDSSQLUpdateObject can be used to transfer changes to the database in a similar fashion.
TIsah7CDSQuery	TIsahCDSQuery	ClientDataSet component with an internal buffer allowing the data retrieved to be changed. By linking the component to an Update object, the changes can be applied to the database.
TIsah7CDSUpdateObject	TIsahCDSStoredProcUpdateObject	Update object that uses stored procedures to transfer changes to the data of a TIsahCDSQuery component to the database.
TScriptSPUpdateObject	TScriptSPUpdateObject	This Update object is similar to the TIsahCDSStoredProcUpdateObject, except that the default value of the CustomizedSPName property is 'True'.
TxUpdateSQL	TIsahCDSSQLUpdateObject	Update object that uses separate queries to transfer changes to the data of a TIsahCDSQuery component to the database.