Basic DDL Operations in MS SQL Server
Getting started
This section describes some basic DDL (=”Data Definition Language”) commands to create a database, a table within a database, a view and finally a stored procedure.
Create Database
The following SQL command creates a new database Northwind
on the current server, using pathC:\Program Files\Microsoft SQL Server\MSSQL11.INSTSQL2012\MSSQL\DATA\
:
USE [master]
GO
CREATE DATABASE [Northwind]
CONTAINMENT = NONE
ON PRIMARY
(
NAME = N'Northwind',
FILENAME = N'C:\Program Files\Microsoft SQL Server\MSSQL11.INSTSQL2012\MSSQL\DATA\Northwind.mdf' , SIZE = 5120KB , MAXSIZE = UNLIMITED, FILEGROWTH = 1024KB
)
LOG ON
(
NAME = N'Northwind_log',
FILENAME = N'C:\Program Files\Microsoft SQL Server\MSSQL11.INSTSQL2012\MSSQL\DATA\Northwind_log.ldf' , SIZE = 1536KB , MAXSIZE = 2048GB , FILEGROWTH = 10%
)
GO
ALTER DATABASE [Northwind] SET COMPATIBILITY_LEVEL = 110
GO
Note: A T-SQL database consists of two files, the database file *.mdf
, and its transaction log *.ldf
. Both need to be specified when a new database is created.
Create Table
The following SQL command creates a new table Categories
in the current database, using schema dbo
(you can switch database context with Use <DatabaseName>
):
CREATE TABLE dbo.Categories(
CategoryID int IDENTITY NOT NULL,
CategoryName nvarchar(15) NOT NULL,
Description ntext NULL,
Picture image NULL,
CONSTRAINT PK_Categories PRIMARY KEY CLUSTERED
(
CategoryID ASC
)
WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF,
ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON PRIMARY
) ON PRIMARY TEXTIMAGE_ON PRIMARY
Create View
The following SQL command creates a new view Summary_of_Sales_by_Year
in the current database, using schema dbo
(you can switch database context with Use <DatabaseName>
):
CREATE VIEW dbo.Summary_of_Sales_by_Year AS
SELECT ord.ShippedDate, ord.OrderID, ordSub.Subtotal
FROM Orders ord
INNER JOIN [Order Subtotals] ordSub ON ord.OrderID = ordSub.OrderID
This will join tables Orders
and [Order Subtotals]
to display the columns ShippedDate
, OrderID
and Subtotal
. Because table [Order Subtotals]
has a blank in its name in the Northwind database, it needs to be enclosed in square brackets.
Create Procedure
The following SQL command creates a new stored procedure CustOrdersDetail
in the current database, using schema dbo
(you can switch database context with Use <DatabaseName>
):
CREATE PROCEDURE dbo.MyCustOrdersDetail @OrderID int, @MinQuantity int=0
AS BEGIN
SELECT ProductName,
UnitPrice=ROUND(Od.UnitPrice, 2),
Quantity,
Discount=CONVERT(int, Discount * 100),
ExtendedPrice=ROUND(CONVERT(money, Quantity * (1 - Discount) * Od.UnitPrice), 2)
FROM Products P, [Order Details] Od
WHERE Od.ProductID = P.ProductID and Od.OrderID = @OrderID
and Od.Quantity>=@MinQuantity
END
This stored procedure, after it has been created, can be invoked as follows:
exec dbo.MyCustOrdersDetail 10248
which will return all order details with @OrderId=10248 (and quantity >=0 as default). Or you can specify the optional parameter
exec dbo.MyCustOrdersDetail 10248, 10
which will return only orders with a minimum quantity of 10 (or more).