1. Using ER/Studio

2. Modeling a Relational Database Using ER Studio
We will use ER Studio as the modeling Tool to build ER diagrams.
ER Studio Is a CASE tool providing a Repository (or System Catalog) of an organization’s databases
Fully specified logical models in ER studio can be used to generate DDL
the code of the create tables statements

3. Getting to ER Studio Data Architect
Enter ERS in the Search are of the start menu
Click on the ER Studio Data Architect 9.6 icon
Click on tools in the top menu and then select options from the drop-down menu

4. Set Options to Produce Crow’s-Foot Notation
Pick logical
Pick options from tools drop-down
Choose Crow’s feet notation

5. Create a New Model
Select File from the top menu and new from the drop down
On the dialog box, ensure that Draw a new data model is checked and that relational is selected, then click OK

6. Select an Entity to Add

7. Entity Editor Name the entity then make sure that the Attributes
tab is selected
and click the Add
button to add
attributes

8. Can specify derived attributes and check this box
Adding Attributes
Can specify derived attributes and check this box
For each attribute
specify its name,
select a datatype
from the listbox,
select the column
width and check
whether nulls are
to be allowed for
the attribute.
Check this box if the attribute is the primary key (or a part of the PK)

9. Other Attribute Properties
Add Default value using the Default tab
Simply add the default value: e.g. a system variable as shown or a ‘Y’ for a flag variable, etc.
Add check constraints using the rule/constraint tab
Note that a constraint name can be specified
Check Constraint Value is the full condition to be applied by the Check constraint
begins the constraint condition with the attribute name
& we just finish out the condition

10. Adding Relationships by Type
identifying
Non- identifying
Optional
Non-identifying
Mandatory

11. Relationship Types Identifying Non-identifying Mandatory
Strong relationship child entity is a weak entity
Primary key of 1st entity becomes a foreign key and part of the primary key of 2nd entity clicked.
Non-identifying Mandatory
Weak relationship child entity is a strong entity
Primary key of 1st entity specified becomes a foreign key in 2nd entity and foreign key attribute is not null
Non-Identifying Optional
Weak relationship child entity is strong
Primary key of 1st entity specified becomes a foreign key in 2nd entity, but the foreign key attribute can be null.

12. Editing Relationship Properties
Auto add of FK

13. Identifying Relationship Specification
For identifying relationships, Primary key of parent is automatically added to primary key of the child table
To complete this specification Phone_No should be added to the primary key of PATRON_PHONE

14. Creating a Sub-Class Hierarchy
First create the Super-Class and sub-Class entities
Add at least the primary key to the super-class entity
From the insert Drop-down, select sub-type cluster, then
pick either complete or incomplete
Click on the super-class entity
Control-click on the first subclass entity & continue until all sub-class have been linked in
(see next slide for menu option, following slide for result.)

15. Choose complete (all super-type members must belong to a sub-type, or incomplete

16. Right click & pick edit subtype cluster to get this Dialog box

17. Saving the Model
Change to desired J drive space

18. Generating the Physical Model

19. Physical Model for Oracle

20. Generated SQL for Data Definition Language--
-- TABLE: ormCustomer
CREATE TABLE ormCustomer(
custnumber NUMBER(10, 0) NOT NULL,
name VARCHAR2(20),
CONSTRAINT PK1 PRIMARY KEY (custnumber) ) ;
-- TABLE: ormOrder
CREATE TABLE ormOrder(
ordernumber NUMBER(10, 0) NOT NULL,
orderdate DATE NOT NULL,
total NUMBER(10, 0),
custnumber NUMBER(10, 0) NOT NULL,
CONSTRAINT PK2 PRIMARY KEY (ordernumber)
ALTER TABLE ormOrder ADD CONSTRAINT ReformCustomer31
FOREIGN KEY (custnumber)
REFERENCES ormCustomer(custnumber)