Sybase 12.4.2 manual Working with views, Table information in the system tables, 127

CHAPTER 3 Working with Database Objects

❖To create an unenforced foreign key in Sybase Central:

1 Connect to the database.

2 Click the Tables folder for that database.

3 Click the table holding the primary key, and drag it to the foreign key table.

4 When the primary key table is dropped on the foreign key table, the Foreign Key Wizard is displayed, which leads you through the process of creating the foreign key.

For more information, see the Sybase Central online Help.

For more information about using primary and foreign keys, see Chapter 7, “Ensuring Data Integrity”

Table information in the system tables

All the information about tables in a database is held in the system tables. The information is distributed among several tables. For more information, see “System Tables” in Adaptive Server IQ Reference Manual.

You can use Sybase Central or DBISQL to browse the information in these tables. Type the following command in the DBISQL command window to see all the columns in the SYS.SYSTABLE table:

SELECT *

FROM SYS.SYSTABLE

❖To display the system tables in Sybase Central:

1 Connect to the database.

2 Right-click the database, and select Filter Objects from the pop-up menu. 3 Select SYS and OK.

4 When you view the database tables or views with Show System Objects checked, the system tables or views are also shown.

Working with views

Views are computed tables. You can use views to show database users exactly the information you want to present, in a format you can control.

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