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T-SQL for Data Definition
Vu Tuyet Trinh
[email protected]
Hanoi University of Technology
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Overview of Transact-SQL
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Based on AINSI SQL 92 standard
Composing of three categories
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Data Manipulation Language (DML)
Data Definition Language (DDL)
Data Control Language (DCL)
Having some Microsoft specific extensions
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Beyond relational data
.net framework integration
Data Definition Language
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Create
used to create databases and their objects.
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Use
allows you to specify the database you wish to work with within
your DBMS.
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Alter
used to modify the definition of it without deleting it
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Drop
used to remove entire database objects
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Overview of Database Objects
Tables
• Data storage &
Retrieval
• Referential
integrity
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Indexes
• Improves
query
performance
• Clustered
• Non-clustered
Views
• Logical result
sets
• Based on
SELECT
queries
Programmability
• Stored
Procedures
• Functions
• Triggers
• Constraints
Outline
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Data Definition Language
Managing Databases
Data Types
Managing Tables
Managing other SQL Server Objects
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Databases in SQL Server

Database
Storing data and other database
objects
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Database Snapshot
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Maintain historical data for report
generation
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Safeguard data against
administrative error
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Safeguard data against user error
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SQL Server
Enterprise Edition
Creating a New Database
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Factors to consider
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Default: Sysadmin, dbcreator
Creator becomes the owner
Maximum of 32,767 per server
Follow naming rules
Creating a New Database
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Some arguments:
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The name of the database
The size of the database
The files where the database will reside
CREATE DATABASE Sample
ON
PRIMARY ( NAME=SampleData,
FILENAME='c:\Program Files\..\..\Data\Sample.mdf',
SIZE=10MB,
MAXSIZE=15MB,
FILEGROWTH=20%)
LOG ON
( NAME=SampleLog,
FILENAME= 'c:\Program Files\..\..\Data\Sample.ldf',
SIZE=3MB,
MAXSIZE=5MB,
FILEGROWTH=1MB)
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COLLATE SQL_Latin1_General_Cp1_CI_AS
Setting & Viewing Database Options
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Set Database Options By Using:
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Database Option Categories
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SQL Server Management Studio
ALTER DATABASE statement
Auto options
Cursor options
Recovery options
SQL options
State options
Retrieving Database Information

Determining database properties by using the
DATABASEPROPERTYEX Function
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Using system stored procedures to display
information about databases and its parameters
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SELECT DATABASEPROPERTYEX
(‘pubs’,’useraccess’)
SELECT DATABASEPROPERTYEX
(‘pubs’,’recovery’)
sp_helpdb
sp_helpdb database_name
sp_spaceused [objname]
Attaching an Existing Database
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Creating a Snapshot Database
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Managing Databases
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Shrinking a Database or File
Dropping a Database
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Shrinking a Database or File
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Shrinking an Entire Database
DBCC SHRINKDATABASE (Sample, 25)
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Shrinking a Data File in the Database
DBCC SHRINKFILE (Sample_Data, 10)
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Shrinking a Database Automatically
Set autoshrink database option to true
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Dropping a Database
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Methods of Dropping a Database
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SQL Server Enterprise Manager
DROP DATABASE statement
DROP DATABASE Northwind, pubs
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Restrictions on Dropping a Database
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While it is being restored
When a user is connected to it
When publishing as part of replication
If it is a system database
Outline
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Data Definition Language
Managing Databases
Data Types
Managing Tables
Managing other SQL Server Objects
Microsoft
Data Types
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System data types
User-defined data type
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CLR types
Spatial data
Filestreams
XML
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System Data Types
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Exact numeric
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Approximate numeric
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nchar, nvarchar, ntext
Binary character string
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char, varchar, text
Unicode character string
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datetime, smalldatetime
Character string
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float, Real
Date & Time
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bit, tinyint, smallint, int, bigint, numeric, decimal, smallmoney, money
binary, varbinary, image
Others
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sql_variant, timestamp, xml…..
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Creating Tables
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Determining column & data type
Determining column nullability
Defining column default values
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Example
CREATE TABLE dbo.Categories
(CategoryID
CategoryName
Description
Picture
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int IDENTITY
(1,1)
nvarchar(15)
ntext
image
NOT NULL,
NOT NULL,
NULL,
NULL)
Modifying Table Definition
ALTER TABLE table_name
{[ALTER COLUMN column_name
{DROP DEFAULT
|SET DEFAULT constant_expression
|IDENTITY [(seed,increment)]}
|ADD
{< column_definition >|< table_constraint>} [
,...n ]
|DROP
{[ CONSTRAINT ] constraint_name
| COLUMN column }
]}
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Example
ADD ALTER TABLE CategoriesNew
ADD Commission money null
Customer_name Sales_amount
Sales_date
DROP
ALTER TABLE CategoriesNew
DROP COLUMN Sales_date
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Customer ID
Commission
Outline
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Data Definition Language
Managing Databases
Data Types
Managing Tables
Managing other SQL Server Objects
Microsoft
Views

What is a view?
Creating a virtual collection of records from existing tables
 Being used for security and/or performance issues

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Creating view
CREATE VIEW [schema_name.]view_name
[(column[,...n])]
[ WITH <view_attribute> [ ,...n ] ]
AS
select_statement
[ WITH CHECK OPTION ] [ ; ]
<view_attribute>::={[ENCRYPTION]
[SCHEMABINDING]
[ VIEW_METADATA ]}
 Removing view
DROP
VIEW { view_name } [ ,...n ]
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Others CREATE/ALTER/DROP… command
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CREATE/ALTER/DROP
CREATE/ALTER/DROP
CREATE/ALTER/DROP
CREATE/ALTER/DROP
CREATE/ALTER/DROP
…
RULE …
PROCEDURE …
FUNCTION …
TRIGGER …
USER …
For further detail information, see [Microsoft SQL Server Books Online ]
Microsoft
Summary
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Data definition language
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Creating and managing database object
Create, Use, Alter, Drop,
 SQL Server database objects
database, table, view, index, …
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Simplifying the management of more complicated data
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Relational data
User-defined Data
 CLR types
Spatial data
Filestreams
XML
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