free barcode generator using vb.net Views in Software

Generator Code 128 Code Set A in Software Views

Views
Code 128 Code Set C Scanner In None
Using Barcode Control SDK for Software Control to generate, create, read, scan barcode image in Software applications.
Code 128 Code Set A Creator In None
Using Barcode generator for Software Control to generate, create Code 128A image in Software applications.
SALESREPS table itself. This effectively gives the sales manager a customized view of the SALESREPS table, showing only salespeople in the appropriate region. A view like EASTREPS or WESTREPS is often called a horizontal view. As shown in Figure 14-3, a horizontal view slices the source table horizontally to create the view. All of the columns of the source table participate in the view, but only some of its rows are visible through the view. Horizontal views are appropriate when the source table contains data that relates to various organizations or users. They provide a private table for each user, composed only of the rows needed by that user. Here are some more examples of horizontal views: Define a view containing only Eastern region offices.
Recognizing Code128 In None
Using Barcode recognizer for Software Control to read, scan read, scan image in Software applications.
Code 128 Code Set C Generator In Visual C#
Using Barcode printer for Visual Studio .NET Control to generate, create Code 128 Code Set A image in .NET framework applications.
CREATE VIEW SELECT FROM WHERE EASTOFFICES AS * OFFICES REGION = 'Eastern'
Code 128 Code Set B Creation In .NET
Using Barcode encoder for ASP.NET Control to generate, create Code 128 Code Set A image in ASP.NET applications.
Code128 Printer In VS .NET
Using Barcode drawer for VS .NET Control to generate, create Code 128C image in .NET framework applications.
DATABASE STRUCTURE
Code 128 Creation In Visual Basic .NET
Using Barcode maker for VS .NET Control to generate, create Code128 image in VS .NET applications.
Printing Data Matrix 2d Barcode In None
Using Barcode creation for Software Control to generate, create Data Matrix image in Software applications.
Figure 14-3.
EAN 128 Generator In None
Using Barcode generation for Software Control to generate, create UCC-128 image in Software applications.
Encode UPC A In None
Using Barcode maker for Software Control to generate, create UCC - 12 image in Software applications.
Two horizontal views of the SALESREPS table
Barcode Generation In None
Using Barcode drawer for Software Control to generate, create barcode image in Software applications.
Barcode Printer In None
Using Barcode generator for Software Control to generate, create barcode image in Software applications.
SQL: The Complete Reference
USD-3 Generation In None
Using Barcode drawer for Software Control to generate, create USS Code 93 image in Software applications.
EAN / UCC - 13 Creation In Java
Using Barcode encoder for Java Control to generate, create EAN 128 image in Java applications.
Define a view for Sue Smith (employee number 102) containing only orders placed by customers assigned to her.
Read GS1 - 12 In .NET Framework
Using Barcode recognizer for .NET Control to read, scan read, scan image in Visual Studio .NET applications.
Print Data Matrix ECC200 In Java
Using Barcode creator for Java Control to generate, create Data Matrix image in Java applications.
CREATE VIEW SELECT FROM WHERE SUEORDERS AS * ORDERS CUST IN (SELECT CUST_NUM FROM CUSTOMERS WHERE CUST_REP = 102)
EAN-13 Creation In None
Using Barcode generation for Microsoft Excel Control to generate, create EAN13 image in Office Excel applications.
Draw GS1 - 12 In Objective-C
Using Barcode drawer for iPhone Control to generate, create UPC-A Supplement 5 image in iPhone applications.
Define a view showing only those customers who have more than $30,000 worth of orders currently on the books.
Create UPC - 13 In Java
Using Barcode drawer for Java Control to generate, create European Article Number 13 image in Java applications.
Matrix Barcode Drawer In Visual Studio .NET
Using Barcode creator for ASP.NET Control to generate, create 2D Barcode image in ASP.NET applications.
CREATE VIEW SELECT FROM WHERE BIGCUSTOMERS AS * CUSTOMERS 30000.00 < (SELECT SUM(AMOUNT) FROM ORDERS WHERE CUST = CUST_NUM)
In each of these examples, the view is derived from a single source table. The view is defined by a SELECT * query and therefore has exactly the same columns as the source table. The WHERE clause determines which rows of the source table are visible in the view.
Vertical Views
Another common use of views is to restrict a user s access to only certain columns of a table. For example, in the sample database, the order-processing department may need access to the employee number, name, and office assignment of each salesperson, because this information may be needed to process an order correctly. However, there is no need for the order-processing staff to see the salesperson s year-to-date sales or quota. This selective view of the SALESREPS table can be constructed with the following view: Create a view showing selected salesperson information.
CREATE VIEW REPINFO AS SELECT EMPL_NUM, NAME, REP_OFFICE FROM SALESREPS
By giving the order-processing staff access to this view and denying access to the SALESREPS table itself, access to sensitive sales and quota data is effectively restricted.
14:
Views
A view like the REPINFO view is often called a vertical view. As shown in Figure 14-4, a vertical view slices the source table vertically to create the view. Vertical views are commonly found where the data stored in a table is used by various users or groups of users. They provide a private table for each user, composed only of the columns needed by that user. Here are some more examples of vertical views: Define a view of the OFFICES table for the order-processing staff that includes the office s city, office number, and region.
CREATE VIEW OFFICEINFO AS SELECT OFFICE, CITY, REGION FROM OFFICES
DATABASE STRUCTURE
Figure 14-4.
A vertical view of the SALESREPS table
SQL: The Complete Reference
Define a view of the CUSTOMERS table that includes only customer names and their assignment to salespeople.
CREATE VIEW CUSTINFO AS SELECT COMPANY, CUST_REP FROM CUSTOMERS
In each of these examples, the view is derived from a single source table. The select list in the view definition determines which columns of the source table are visible in the view. Because these are vertical views, every row of the source table is represented in the view, and the view definition does not include a WHERE clause.
Row/Column Subset Views
When you define a view, SQL does not restrict you to purely horizontal or vertical slices of a table. In fact, the SQL language does not include the notion of horizontal and vertical views. These concepts merely help you to visualize how the view presents the information from the source table. It s quite common to define a view that slices a source table in both the horizontal and vertical dimensions, as in this example: Define a view that contains the customer number, company name, and credit limit of all customers assigned to Bill Adams (employee number 105).
Copyright © OnBarcode.com . All rights reserved.