Using Quick Select  Selecting columns

Chapter 18: Defining DataWindow Objects

Selecting a table

When you choose Quick Select, the Quick Select dialog box displays. The Tables box lists tables and views in the current database.

NoteDisplaying table comments To display a comment about a table, position the pointer on the table and click the right mouse button or select the table.

Which tables and views display?

The DBMS determines what tables and views display. For some DBMSs, all tables and views display, whether or not you have authorization. If you select a table or view you are not authorized to access, the DBMS issues a message.

For ODBC databases, the tables and views that display depend on the driver for the data source. Adaptive Server Anywhere does not restrict the display, so all tables and views display, whether or not you have authorization.

Tables with key relationships

When you select a table, the table's column names display in the Columns box, and any tables having a key relationship with the selected table display in the Tables box. These tables are indented and marked with an arrow to show their relationship to the selected table. You can select any of these related tables if you want to include columns from them in the DataWindow object.

The sample Quick Select dialog box shows the Tables box at left with employee table selected. Indented below the employee table are the related department and sales _ order tables. Under the box is a comment line, "A list of all employees within the company." A Column box on the right lists the columns for the employee table. At the bottom is a scrollable area for entering text with labels that read column, sort, criteria, or.

Meaning of the up and down arrows

An arrow displays next to a table to indicate its relationship to the selected table. The arrow always points in the many direction of the relationship—toward the selected table (up) if the selected table contains a foreign key in the relationship and away from the selected table (down) if the selected table contains a primary key in the relationship:

In the sample, the selected table is sales _ order. Indented under it are customer, employee, and fin _ code, each followed by an Up arrow to indicate that a foreign key in the sales _ order table is mapped to their primary keys. Also indented under sales _ order is sales _ order _ items with a Down arrow indicating that the sales _ order _ items table contains a foreign key mapped to the primary key in the sales _ order table.

In this preceding illustration, the selected table is sales_order. The Up arrows indicate that a foreign key in the sales_order table is mapped to the primary key in the customer and fin_code tables. The Down arrow indicates that the sales_order_items table contains a foreign key mapped to the primary key in the sales_order table.

How columns from additional tables display

The column names of selected tables display in the Columns box. If you select more than one table, the column names are identified as:

tablename.columnname

For example, department.dept_name and employee.emp_id display when the Employee table and the Department table are selected.

NoteTo return to the original table list Click the table you first selected at the top of the table list.




Copyright © 2006. Sybase Inc. All rights reserved. Selecting columns

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