2: SQL Server 2005 Database Basics in .NET framework

Make QR Code ISO/IEC18004 in .NET framework 2: SQL Server 2005 Database Basics

2: SQL Server 2005 Database Basics
Draw Quick Response Code In Visual Studio .NET
Using Barcode generation for Reporting Service Control to generate, create QR Code image in Reporting Service applications.
Making Bar Code In VS .NET
Using Barcode generator for Reporting Service Control to generate, create barcode image in Reporting Service applications.
3 C, D Indexes can not be created on computed columns that are nondeterministic Computations based on the date (such as Month or GetDate functions) are nondeterministic 4 D A computed column can be created to display the data in the different collation There is no need to create completely different databases or tables to achieve the result 5 True The primary restriction on creating indexes on computed columns is that the computed column must be nondeterministic and precise Simply changing the collation would result in both a deterministic and precise result
Painting QR Code In C#.NET
Using Barcode creation for Visual Studio .NET Control to generate, create QR Code 2d barcode image in .NET framework applications.
QR Code Encoder In VS .NET
Using Barcode maker for ASP.NET Control to generate, create QR-Code image in ASP.NET applications.
This page intentionally left blank
Quick Response Code Maker In VS .NET
Using Barcode generation for .NET Control to generate, create QR Code image in .NET framework applications.
QR Code Generator In VB.NET
Using Barcode drawer for .NET Control to generate, create QR Code image in .NET applications.
CHAPTER
EAN13 Creation In Visual Studio .NET
Using Barcode generation for Reporting Service Control to generate, create EAN / UCC - 13 image in Reporting Service applications.
Create ECC200 In .NET
Using Barcode generator for Reporting Service Control to generate, create Data Matrix ECC200 image in Reporting Service applications.
Database Design
Print UCC - 12 In .NET Framework
Using Barcode creation for Reporting Service Control to generate, create UCC - 12 image in Reporting Service applications.
Bar Code Generator In Visual Studio .NET
Using Barcode creation for Reporting Service Control to generate, create bar code image in Reporting Service applications.
In this chapter, you will learn about: Data integrity PRIMARY and FOREIGN KEY constraints Normalization and denormalization CHECK constraints Partitioning tables via horizontal partitioning or partition schemes Database design through an exercise
Printing Barcode In .NET
Using Barcode encoder for Reporting Service Control to generate, create barcode image in Reporting Service applications.
Draw Code 128 In VS .NET
Using Barcode drawer for Reporting Service Control to generate, create USS Code 128 image in Reporting Service applications.
Beauty of style and harmony and grace and good rhythm depend on simplicity Plato
Printing USPS Confirm Service Barcode In .NET Framework
Using Barcode generation for Reporting Service Control to generate, create USPS PLANET Barcode image in Reporting Service applications.
Make Code 3/9 In None
Using Barcode creator for Software Control to generate, create USS Code 39 image in Software applications.
Simplicity No matter what you re designing from a graceful garden to a dynamic database much of the beauty comes from the simplicity of the design In databases, we achieve simplicity by normalizing a database In 2, we presented basic data types and tables In this chapter, we ll add multiple tables and show how the tables can be related with PRIMARY and FOREIGN KEYs The normalization section of this chapter shows how you can reduce complex tables to their simplest form to ensure the functionality of a database You ll see how some basic business rules can be enforced by implementing constraints and checks And you ll learn how very large tables can be partitioned to increase performance of queries To help you solidify your understanding, we tie the chapter together with a database design exercise
Code-39 Reader In None
Using Barcode reader for Software Control to read, scan read, scan image in Software applications.
Print Bar Code In Objective-C
Using Barcode encoder for iPhone Control to generate, create barcode image in iPhone applications.
Data Integrity
Encode UCC - 12 In Java
Using Barcode creator for BIRT reports Control to generate, create GS1 - 12 image in Eclipse BIRT applications.
Barcode Drawer In None
Using Barcode maker for Font Control to generate, create bar code image in Font applications.
One of the basic challenges of any databases is ensuring that we have quality data A huge database with bogus and/or inconsistent data is only marginally better than no data at all What we do with any database is implement different methods to ensure the integrity of the data
Reading GS1 128 In VB.NET
Using Barcode recognizer for Visual Studio .NET Control to read, scan read, scan image in .NET framework applications.
UCC - 12 Drawer In None
Using Barcode encoder for Office Excel Control to generate, create UCC - 12 image in Microsoft Excel applications.
Copyright 2008 by The McGraw-Hill Companies Click here for terms of use
MCITP SQL Server 2005 Database Developer All-in-One Exam Guide
Constraints are used to enforce data integrity by constraining, or restricting, the data that can be entered into a database The different types of constraints that can be used to enforce data integrity are:
NOT NULL This specifies that a column does not accept NULL values, or in other words, data must be entered We covered NULL and NOT NULL in 2 PRIMARY KEY The PRIMARY KEY is used to ensure that each row within a table is unique The PRIMARY KEY does not allow NULL values (This will be covered in depth in this chapter) FOREIGN KEY A FOREIGN KEY is used to create and enforce relationships between two tables A FOREIGN KEY in one table typically references a PRIMARY KEY in another table (though it can also reference a column identified with the UNIQUE constraint) (FOREIGN KEYS will be covered in depth in this chapter) CHECK The CHECK constraint allows us to limit the values that can be put into a column We have a wide range of capabilities of limiting values that will be covered in more depth later in this chapter UNIQUE The UNIQUE constraint is used to ensure that all values within a column are unique This can be used on tables that have a PRIMARY KEY but need another column that must have each column unique The UNIQUE constraint allows a NULL value
We have three types of data integrity to consider in database design These are outlined in Table 3-1
Type of Integrity Affects Method
Domain Entity Referential
Columns Rows Relationships
Data types, defaults, trigger constraints PRIMARY KEY constraints PRIMARY KEY and FOREIGN KEY constraints
Table 3-1 Types of Data Integrity
With domain integrity, we try to ensure that the data entered is valid We don t necessarily know that the data is accurate, but we can ensure it s valid For example, if we have a phone number in a table, we could set the data type as char(13), and if someone accidentally entered the wrong number of characters, we d know that the data isn t valid and we could restrict the entry Constraints allow us to do more sophisticated checking than a basic data type, such as making sure the phone number is entered and formatted exactly how we want it, such as ( # # # ) # # # - # # # #, where # is any number between 0 and 9 If the parentheses and dash are entered where we specify and the numbers are entered where the number symbol is located, we know the data is valid and in the right format (though we still don t know if it is accurate) Entity integrity affects the table and requires that all rows be unique We enforce this with a PRIMARY KEY (PK) constraint
Copyright © OnBarcode.com . All rights reserved.