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"Everyone is a
genius at least once a year; a real genius has his original
ideas closer together." - Georg Lichtenberg (1742-1799) |
Introduction to Schema
Builder
Introduction
Schema Builder allows you
to define the tables, views, snapshots, synonyms, constraints, and
table relationships that will make up your database. You can visualize
your database design, including the tables, columns, data types, and
relationships, and then execute that design.
Hands-On
In this Hands-On, you will
learn how to: Create the “students” table, Define columns, Define
attributes, Define Primary key, Define require field, Define Unique
Key, Grant Privileges to public, Check what other users can access,
Remove table, and Check table access.
Open Schema Builder tool
Open the “Schema Builder”
tool.
Login as “iself”
password “schooling,” and click on “connect.”
Click on the “OK”
button.
Maximize the window if
needed.
Create a table
Choose the “Schema”
option, select “Create Table”, then click on ”Table.”
You should see the ‘+’
sign next to your cursor. Drag your “+” sign cursor and release
it.
Resize your object if
needed.
Rename a table
Choose the “Data”
option and click on “Rename Table.”
In the ‘Rename Table’
window, change the “Table1” name to “Students,” and then click
“OK” to rename the table.
Add columns and attributes
Click on the plus sign next
to the ‘COLUMN1’ object to add new columns.
In the ‘Define Column’
window in the ‘Column Name’ box, type “Student_id;” its column
attributes; and make it a Primary Key. Use any reasonable attributes
to your column (Data type, Length, Default value, Primary key, Unique
Key, or Required). Notice on the different attribute options available
to you in the ‘Data Type’ box.
Click on "new
column."
Type "first_name,"
its column attributes; and make it a required field.
Click on "new
column."
Type "last_name,"
its column attributes; and make it a required field.
Click on "new
column."
Type "ssn" for
social security number, its column attributes; and make it an unique
key.
Click “OK.” Your table
will be created.
SQL statement
To check on the SQL
statement, choose the "schema” option, and click on "Show
SQL." Now, you should be able to see your SQL statement in the
‘Schema Editor: Show SQL’ window.
Save table in the database
To save your table in the
database, click on “COMMIT” to create the table, and then
Close the window.
Now, the table was created.
Grant access privileges
To assign or grant
privileges to others to access to your tables, choose the
"File" option, and click on "Set privileges.”
In the ‘Set Schema
Privileges’ window, you will see all your tables and all the Roles
privileges that you are able to grant.
Assign the “Students”
table to the public. Select the ‘Students’ table and the ‘PUBLIC’
role by highlighting them. Notice that the ‘Privileges’ box will
change to white from gray.
Give select and insert
privileges to the public by check mark them.
Click on "apply,"
and then close the window.
Now, the public users can
only “insert” and “select” from the table.
Drop a table
Now, let’s drop the
table.
Choose the “Schema"
option and click on “Remove.”
The gray color indicates
the object was removed.
Exit from “schema
builder," and Click on "yes" to commit changes.
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"Everyone is a
genius at least once a year; a real genius has his original
ideas closer together." - Georg Lichtenberg (1742-1799) |
Questions:
Q: How can you create a
table using the "Schema Builder" tool?
Q: How can you define a
column, attribute, and primary key using the "Schema
Builder" tool?.
Q: How can you define a
required field and unique key using the "Schema Builder"
tool?.
Q: How can you grant an
object privilege to the public using the "Schema Builder"
tool?
Q: How can you check
what other users can access using the "Schema Builder" tool?
Q: How can you remove a
table using the "Schema Builder" tool?
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