Teach Yourself Borland C++ in 14 Days - portal

460 Day 12
Table 12.16. continued
Event Catalyst
OnCalcFields Occurs when calculated fields need values.
OnDeleteError Occurs when there is a problem deleting a record.
OnEditError Occurs when there is a problem editing a record.
OnFilterRecord Occurs when filtering is active and the TDataset needs a row.
OnNewRecord Occurs when a new record is added to the TDataset.
OnPostError Occurs when there is a problem posting a record.
OnUpdateError Occurs when there is a problem while applying cached updates.
OnUpdateRecord Occurs for each row saved by a call to ApplyUpdates.
Key Elements
Use the DatabaseName property to specify the database you want to access. It points to either
a local, application-specific alias or one that you’ve defined using the Database Explorer or
BDE Configuration utility.
The StoredProcName property points to the stored procedure on the server that you want to
execute.
The Params property enables you to specify parameters for the stored procedure. You can edit
this information at design time using the C++Builder Object Inspector. If the information
is available from the server, the Object Inspector will list the parameters that the stored
procedure expects.
NOTE
You can set these parameters at runtime by assigning values to the Params property. For
example, you could use the following code to assign the parameter named CustomerNumber
for the stored procedure associated with the TStoredProc:
StoredProc1->ParamByName(“CustomerNumber”)->AsString = “123”;
Note that stored procedure return values are accessed using the Params property, as well. That
is, if you’ve defined an output parameter named Balance in the Params property, you can
reference its return value using ParamByName(“Balance”)->AsFloat following the execution
of the procedure.
If you intend to return output parameters from a Sybase stored
procedure that also returns a result set, you’ll need to call TStoredProc’s
GetResults method in order to retrieve them. Normally, the