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466 Day 12
Table 12.22 lists the key properties and Table 12.23 lists the key methods of the TUpdateSQL
component. There are no key events for the TUpdateSQL component.
Table 12.22. TUpdateSQL key properties.
Property Description
DeleteSQL Specifies the SQL to execute when a row is deleted.
InsertSQL Specifies the SQL to execute when a row is added.
ModifySQL Specifies the SQL to execute when a row is updated.
Table 12.23. TUpdateSQL key methods.
Method Function
Apply Replaces parameters in and calls the SQL you specify (DeleteSQL,
InsertSQL, or ModifySQL). Calls both SetParams and ExecSQL.
ExecSQL Executes DeleteSQL, InsertSQL, or ModifySQL, as specified.
SetParams Replaces the parameters in DeleteSQL, InsertSQL, or ModifySQL, as
specified.
Key Elements
The InsertSQL, ModifySQL, and DeleteSQL properties provide the means of controlling
updates to TDatasets. These TDatasets can be TTables, TQuery result sets, or TStoredProc
result sets. The SQL you specify can be a simple SQL INSERT, UPDATE, or DELETE statement.
It can be a complex SQL query and can even consist of a call to a stored procedure. This
flexibility gives you the control you need to update almost any type of result set.
Tasks
To make use of a TUpdateSQL component, follow these steps:
1. Drop a TUpdateSQL component on a form and set its InsertSQL, DeleteSQL, and
ModifySQL statements to update the database object(s) referenced by your TDataset.
2. Set the TDataset’s UpdateObject property to point to your TUpdateSQL component.
3. Set the TDataset’s CachedUpdates property to true.
4. Call the ApplyUpdates command from within your application when you want to
invoke the SQL specified in the TUpdateSQL component.