ER/Studio - Embarcadero Technologies Product Documentation

USING ER/STUDIO > DEVELOPING THE PHYSICAL MODEL
Description tab
Includes a text box where you can enter a Trigger description.
Attachment Bindings tab
Bind an external piece of information, or attachment to the trigger. You can also remove an attachment from an
object, override an attachment binding’s default value, or change the position of a bound attachment. To override
the value of the attachment you have moved to the Selected Attachments grid, double-click the Value field of the
target attachment. ER/Studio opens the Value Override Editor or a list depending on the attachment datatype.
Attachments are created in the Attachments folder of the Data Dictionary. For more information, see Attaching
External Documents to the Data Model.
Create a Templated User-Defined Trigger
1 In the Data Model Explorer, expand the Physical Main Model, right-click the Triggers node, and then click New
Trigger.
2 Complete the Trigger Wizard and then click Finish to create the trigger.
TIP: Once you have created the auxiliary table, you can edit it by right-clicking the auxiliary table you
want to change, and then selecting Edit Auxiliary Table.
The following describe options that require additional explanation:
• The Trigger Editor includes find and replace functionality for working with SQL text strings.
• In order for code to be generated for procedural logic such as triggers and procedures, the results of the
trigger must be stored in a variable called resultstring. For example, in the Northwind.dm1 sample model,
the Data Dictionary lists a reusable trigger, SYSUPDATE, for the the Oracle platform. The code for this trigger
includes the following statement, which is required for code to be generated for the trigger:
resultstring = trigBody
Description page/tab
Enter or edit a definition for the description. If the target database supports it, ER/Studio adds this definition as a
comment when generating SQL code.
Attachment Bindings tab
Bind an external piece of information, or attachment to the trigger. You can also remove an attachment from an
object, override an attachment binding’s default value, or change the position of a bound attachment. To override
the value of the attachment you have moved to the Selected Attachments grid, double-click the Value field of the
target attachment. ER/Studio opens the Value Override Editor or a list depending on the attachment datatype.
Attachments are created in the Attachments folder of the Data Dictionary. For more information, see Attaching
External Documents to the Data Model.
Create a Reusable User-Defined Trigger
Reusable user-defined triggers are created in the Data Dictionary. For more information, see Create and Edit
Reusable Triggers
Creating and Editing Functions
Functions are subroutines that you define. Functions can be written in a programming language such as C, COBOL,
or Java that returns a scalar value or a complete table, or they can call another function, or they can be written in SQL
and return a scalar value. Functions are useful for reusable application logic. You can use functions to determine the
best methods for controlling access and manipulation of the underlying data contained in an object. Functions accept
a number of parameters and pass a single value back to the calling program. Functions can be used in the database
to check the validity of the data being entered. For example, functions can be used to validate zip codes. By invoking a
routine with the zip code, the function can return a true or false value based on if the zip code is valid.
EMBARCADERO TECHNOLOGIES > ER/STUDIO® 8.0.3 USER GUIDE 191