C# and Databases - City University of New Yorknatacha/TeachSpring_2013/CSC... · way that is...

CSC 330 Object Oriented CSC 330 Object Oriented ProgrammingProgramming

C# and DatabasesC# and Databases

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IntroductionIntroduction

Database:Integrated collection of dataDatabase management system (DBMS)

Provides mechanisms for storing and organizing data in a way that is consistent with database’s formatAllows storage and access to database without knowledge of internal representation

Relational Databases most popularUse Structured Query Language to perform queries (search) and manipulate dataProgramming languages need an interface to interact with relational databases

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Introduction to Database Management SystemIntroduction to Database Management System

A database management system (DBMS) is software that manages large collections of data

It is designed to store, retrieve, and manipulate dataA C# application can interact with a DBMS through a 3-layer manipulation

Application: interacts with the user and sends instructions to DBMSDBMS: works directly with the data and sends the result back to the applicationData: the data stored in DBMS

Data

DBMS

Application

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What are Databases?What are Databases?

Features of DBMSDefinition of data structure Maintenance facilityAllow access to and storage of data independently of the internal representation of data

Main job of the DBMS is to ensureensure datadata integrityintegrity

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Relational Database Systems and SQLRelational Database Systems and SQL

Relational database systems are the most popular today (Microsoft Access is a relational database system)SQL is international standard language used with relational database systems to perform queries (i.e. to request information that satisfies given criteria) and to manipulate dataSome popular relational database management systems (RDBMS) are Microsoft SQL Server, Oracle, MySQL, Sybase

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Relational Database ModelRelational Database Model

Logical representation of data:Relationships can be considered without concern for physical structure of data

Composed of tablesRows called recordsColumns called fieldsPrimary key: field that contains unique data

Each record can be identified by at least one distinct value

New sets made from queries called result sets

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Tables, Rows, and ColumnsTables, Rows, and Columns

Data stored in a database are organized into tables, rows, and columnsEach table holds a collection of related data

A table is a two-dimensional container made of rows and columnsA row is a complete set of information about a single itemA column holds an individual piece of information about the item

Name Phone

Katie Allen 555-1234

Jill Ammons 555-5678

Kevin Brown 555-9012

Elisa Garcia 555-3456

Jeff Jenkins 555-7890

Each row contains data about one person

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Column Data TypesColumn Data Types

When you create a database table, you must specify a data type for the column Acceptable data types are defined by DBMS, not C#

SQL Server Data Type

Description Corresponding C# or .NET Framework Data Type

bit True/false values bool

datetime A date and a time DateTime

decimal(t, d) A decimal value with t total digits and d digits appearing after the decimal point. decimal

float Real numbers double

int An integer number int

money Values that represent currency decimal

nchar(n) A fixed-length Unicode string with a maximum length of n characters. string

nvarchar(n) A variable-length Unicode string with a maximum length of n characters. string

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Relational Database ModelRelational Database ModelRelational Database Model

All information is contained in tables (or relationsrelations)

TupleTuple or row (record)AttributeAttribute or column (field)Relationships [not why called relational]

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Relation InstanceRelation InstanceThe current values (relation instance) of a relation are specified by a tableAn element t of r is a tuple, represented by a row in a table

JonesSmithCurryLindsay

customer_name

MainNorthNorthPark

customer_street

HarrisonRyeRyePittsfield

customer_city

customer

attributes(or columns)

tuples(or rows)

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Relational Database ModelRelational Database Model

Relationships are logical representation of data:Not concerned with physical structure

PrimaryPrimary keykey: field that contains unique dataEach record can be identified by at least one distinct valuenumber name department salary location

23603 Jones 413 1100 New Jersey

24568 Kerwin 413 2000 New Jersey

34589 Larson 642 1800 Los Angeles

35761 Myers 611 1400 Orlando

47132 Neumann 413 9000 New Jersey

78321 Stephens 611 8500 Orlando

record/row

field/columnprimary key

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Primary KeysPrimary Keys

Most database tables have a primary keyA primary key is a column that can be used to identify a specific rowThe column that is designated as the primary key must hold a unique value for each row. For example,

Employee ID, social security number, invoice number, sales order numberSometimes the data that you want to store in a table does not contain any unique items that can be used as a primary key

You need to create an identity column specifically to serve as the primary key. This column is known as an identify column.Identify columns typically contain integersEach time a new row is added to the table, the DBMS automatically assigns a unique value to the identify column

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Primary KeysPrimary Keys

Relational DBMS enforces several constraints on dataRuleRule ofof EntityEntity IntegrityIntegrity: in most cases every record has a unique value in its primary-key fieldPrimary key does not have to be a single fieldCompoundCompound PrimaryPrimary KeyKey: when a record has a unique key based on a combination of two fields

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Foreign KeysForeign Keys

A foreignforeign keykey is used to create relationships:Field for which every entry has a unique value in another table and where the field in the other table is the primary key for that table

RuleRule ofof ReferentialReferential IntegrityIntegrity: every foreign-key field value must appear in another table’s primary-key fieldOneOne toto manymany relationshiprelationship: A foreign key can appear many times in its own table, but only once as primary key in another table

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Relational Database Overview: Relational Database Overview: Books DatabaseBooks Database

Rule of Entity Integrity: in most cases every record every record hasaunique value in its primary-key fieldCompound Primary key: when a record has a unique key based on a combination of two fieldsForeign key:

Field for which every entry has a unique value in another table and where the field in the other table is the primary key for that tableRule of Referential Integrity: every foreign-key field value must appear in another table’s primary-key fieldOne to many relationship: A foreign key can appear many times inits own table, but only once as primary key in another table

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Relational Database Overview: Relational Database Overview: BooksBooks DatabaseDatabase

Field Desc rip tion authorID Author’s ID number in the database. In the Books database, this int field is

defined as an auto-incremented field. For each new record inserted in this table, the database increments the authorID value, ensuring that each record has a unique authorID. This field represents the table’s primary key.

firstName Author’s first name (a string). lastName Author’s last name (a string). Fig. 19.3 Authors tab le from Books.

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authorID firstName lastName 1 Harvey Deitel

2 Paul Deitel

3 Tem Nieto

4 Kate Steinbuhler

5 Sean Santry

6 Ted Lin

7 Praveen Sadhu

8 David McPhie

9 Cheryl Yaeger

10 Marina Zlatkina

11 Ben Wiedermann

12 Jonathan Liperi

13 Jeffrey Listfield

Fig. 19.4 Data from the Authors tab le of Books.

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Field Description publisherID The publisher’s ID number in the database. This auto-incremented int

field is the table’s primary-key field.

publisherName The name of the publisher (a string). Fig. 19.5 Publishers table from Books.

publisherID publisherName 1 Prentice Hall

2 Prentice Hall PTG Fig. 19.6 Data from the Publishers tab le of Books.

Fie ld Desc rip tion authorID The author’s ID number, which allows the database to associate each

book with a specific author. The integer ID number in this field must also appear in the Authors table.

isbn The ISBN number for a book (a string). Fig. 19.7 AuthorISBN ta b le from Books.

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a u t h o r I D i s b n a u t h o r I D i s b n 1 0 1 3 0 8 9 5 7 2 5 2 0 1 3 9 1 6 3 0 5 0

1 0 1 3 2 2 6 1 1 9 7 2 0 1 3 0 2 8 4 1 9 x 1 0 1 3 0 8 9 5 7 1 7 2 0 1 3 0 1 6 1 4 3 8 1 0 1 3 5 2 8 9 1 0 6 2 0 1 3 0 8 5 6 1 1 8 1 0 1 3 9 1 6 3 0 5 0 2 0 1 3 0 1 2 5 0 7 5 1 0 1 3 0 2 8 4 1 9 x 2 0 1 3 8 9 9 3 9 4 7 1 0 1 3 0 1 6 1 4 3 8 2 0 1 3 0 8 5 2 4 7 3 1 0 1 3 0 8 5 6 1 1 8 2 0 1 3 0 8 2 9 2 7 7 1 0 1 3 0 1 2 5 0 7 5 2 0 1 3 4 5 6 9 5 5 5 1 0 1 3 8 9 9 3 9 4 7 2 0 1 3 0 8 2 9 2 9 3 1 0 1 3 0 8 5 2 4 7 3 2 0 1 3 0 2 8 4 1 7 3 1 0 1 3 0 8 2 9 2 7 7 2 0 1 3 0 2 8 4 1 8 1 1 0 1 3 4 5 6 9 5 5 5 2 0 1 3 0 8 9 5 6 0 1 1 0 1 3 0 8 2 9 2 9 3 3 0 1 3 0 2 8 4 1 9 x 1 0 1 3 0 2 8 4 1 7 3 3 0 1 3 0 1 6 1 4 3 8 1 0 1 3 0 2 8 4 1 8 1 3 0 1 3 0 8 5 6 1 1 8 1 0 1 3 0 8 9 5 6 0 1 3 0 1 3 4 5 6 9 5 5 5 2 0 1 3 0 8 9 5 7 2 5 3 0 1 3 0 8 2 9 2 9 3 2 0 1 3 2 2 6 1 1 9 7 3 0 1 3 0 2 8 4 1 7 3 2 0 1 3 0 8 9 5 7 1 7 3 0 1 3 0 2 8 4 1 8 1 2 0 1 3 5 2 8 9 1 0 6 4 0 1 3 0 8 9 5 6 0 1

Fig . 1 9 .8 D a t a f ro m A u t h o r I S B N t a b le in B o o k s .

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Fie ld Desc rip tion isbn ISBN number of the book (a string).

title Title of the book (a string). editionNumber Edition number of the book (a string). copyright Copyright year of the book (an int). publisherID Publisher’s ID number (an int). This value must correspond to an ID

number in the Publishers table. imageFile Name of the file containing the book’s cover image (a string). price Suggested retail price of the book (a real number). [Note: The prices

shown in this database are for example purposes only.]

Fig. 19.9 Titles ta b le from Books.

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i s b n t i t l e e d i t i o n -N u m b e r

p u b l i s h - e r I D

c o p y -r i g h t

i m a g e F i l e p r i c e

0 1 3 0 9 2 3 6 1 3 P y t h o n H o w t o P r o g r a m

1 1 2 0 0 2 p y t h o n . j p g $ 6 9 . 9 5

0 1 3 0 6 2 2 2 1 4 C # H o w t o P r o g r a m

1 1 2 0 0 2 c s h t p . j p g $ 6 9 . 9 5

0 1 3 0 3 4 1 5 1 7 J a v a H o w t o P r o g r a m

4 1 2 0 0 2 j h t p 4 . j p g $ 6 9 . 9 5

0 1 3 0 6 4 9 3 4 1 T h e C o m p l e t e J a v a T r a i n i n g C o u r s e

4 2 2 0 0 2 j a v a c t c 4 . j p g $ 1 0 9 . 9 5

0 1 3 0 8 9 5 6 0 1 A d v a n c e d J a v a 2 P l a t f o r m H o w t o P r o g r a m

1 1 2 0 0 2 a d v j h t p 1 . j p g $ 6 9 . 9 5

0 1 3 0 3 0 8 9 7 8 I n t e r n e t a n d W o r l d W i d e W e b H o w t o P r o g r a m

2 1 2 0 0 2 i w 3 h t p 2 . j p g $ 6 9 . 9 5

0 1 3 0 2 9 3 6 3 6 V i s u a l B a s i c . N E T H o w t o P r o g r a m

2 1 2 0 0 2 v b n e t . j p g $ 6 9 . 9 5

0 1 3 0 8 9 5 6 3 6 T h e C o m p l e t e C + + T r a i n i n g C o u r s e

3 2 2 0 0 1 c p p c t c 3 . j p g $ 1 0 9 . 9 5

0 1 3 0 8 9 5 5 1 2 T h e C o m p l e t e e -B u s i n e s s & e -C o m m e r c e P r o g r a m m i n g T r a i n i n g C o u r s e

1 2 2 0 0 1 e b e c c t c . j p g $ 1 0 9 . 9 5

0 1 3 0 8 9 5 6 1 X T h e C o m p l e t e I n t e r n e t & W o r l d W i d e W e b P r o g r a m m i n g T r a i n i n g C o u r s e

2 2 2 0 0 1 i w 3 c t c 2 . j p g $ 1 0 9 . 9 5

0 1 3 0 8 9 5 5 4 7 T h e C o m p l e t e P e r l T r a i n i n g C o u r s e

1 2 2 0 0 1 p e r l . j p g $ 1 0 9 . 9 5

0 1 3 0 8 9 5 5 6 3 T h e C o m p l e t e X M L P r o g r a m m i n g T r a i n i n g C o u r s e

1 2 2 0 0 1 x m l c t c . j p g $ 1 0 9 . 9 5

Fig. 19.10 part 1

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0 1 3 0 8 9 5 7 2 5 C H o w t o P r o g r a m 3 1 2 0 0 1 c h t p 3 . j p g $ 6 9 . 9 5

0 1 3 0 8 9 5 7 1 7 C + + H o w t o P r o g r a m

3 1 2 0 0 1 c p p h t p 3 . j p g $ 6 9 . 9 5

0 1 3 0 2 8 4 1 9 X e - B u s i n e s s a n d e -C o m m e r c e H o w t o P r o g r a m

1 1 2 0 0 1 e b e c h t p 1 . j p g $ 6 9 . 9 5

0 1 3 0 6 2 2 2 6 5 W i r e l e s s I n t e r n e t a n d M o b i l e B u s i n e s s H o w t o P r o g r a m

1 1 2 0 0 1 w i r e l e s s . j p g $ 6 9 . 9 5

0 1 3 0 2 8 4 1 8 1 P e r l H o w t o P r o g r a m

1 1 2 0 0 1 p e r l h t p 1 . j p g $ 6 9 . 9 5

0 1 3 0 2 8 4 1 7 3 X M L H o w t o P r o g r a m

1 1 2 0 0 1 x m l h t p 1 . j p g $ 6 9 . 9 5

0 1 3 0 8 5 6 1 1 8 T h e C o m p l e t e I n t e r n e t a n d W o r l d W i d e W e b P r o g r a m m i n g T r a i n i n g C o u r s e

1 2 2 0 0 0 i w 3 c t c 1 . j p g $ 1 0 9 . 9 5

0 1 3 0 1 2 5 0 7 5 J a v a H o w t o P r o g r a m ( J a v a 2 )

3 1 2 0 0 0 j h t p 3 . j p g $ 6 9 . 9 5

0 1 3 0 8 5 2 4 8 1 T h e C o m p l e t e J a v a 2 T r a i n i n g C o u r s e

3 2 2 0 0 0 j a v a c t c 3 . j p g $ 1 0 9 . 9 5

0 1 3 0 3 2 3 6 4 0 e - B u s i n e s s a n d e -C o m m e r c e f o r M a n a g e r s

1 1 2 0 0 0 e b e c m . j p g $ 6 9 . 9 5


1 1 2 0 0 0 i w 3 h t p 1 . j p g $ 6 9 . 9 5

0 1 3 0 1 3 2 4 9 7 G e t t i n g S t a r t e d w i t h V i s u a l C + + 6 w i t h a n I n t r o d u c t i o n t o M F C

1 1 1 9 9 9 g s v c . j p g $ 4 9 . 9 5

Fig. 19.10 part 2

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0 1 3 0 8 2 9 2 9 3 T h e C o m p le t e V is u a l B a s ic 6 T ra in in g C o u rs e

1 2 1 9 9 9 v b c t c 1 . j p g $ 1 0 9 .9 5

0 1 3 4 5 6 9 5 5 5 V is u a l B a s ic 6 H o w to P r o g r a m

1 1 1 9 9 9 v b h t p 1 . j p g $ 6 9 .9 5

0 1 3 2 7 1 9 7 4 6 J a v a M u lt im e d ia C yb er C la s s r o o m

1 2 1 9 9 8 j a v a c t c . j p g $ 1 0 9 .9 5

0 1 3 6 3 2 5 8 9 0 J a v a H o w to P ro g ra m

1 1 1 9 9 8 j h t p 1 . j p g $ 6 9 .9 5

0 1 3 9 1 6 3 0 5 0 T h e C o m p le t e C + + T ra in in g C o u rs e

2 2 1 9 9 8 c p p c t c 2 . j p g $ 1 0 9 .9 5

0 1 3 5 2 8 9 1 0 6 C + + H o w t o P ro g ra m

2 1 1 9 9 8 c p p h t p 2 . j p g $ 4 9 .9 5

0 1 3 7 9 0 5 6 9 6 T h e C o m p le t e J a v a T ra in in g C o u rs e

2 2 1 9 9 8 j a v a c t c 2 . j p g $ 1 0 9 .9 5

0 1 3 0 8 2 9 2 7 7 T h e C o m p le t e J a v a T ra in in g C o u rs e (J a v a 1 .1 )

2 2 1 9 9 8 j a v a c t c 2 . j p g $ 9 9 .9 5

0 1 3 8 9 9 3 9 4 7 J a v a H o w to P ro g ra m (J a v a 1 .1 )

2 1 1 9 9 8 j h t p 2 . j p g $ 4 9 .9 5

0 1 3 1 1 7 3 3 4 0 C + + H o w t o P ro g ra m

1 1 1 9 9 4 c p p h t p 1 . j p g $ 6 9 .9 5

0 1 3 2 2 6 1 1 9 7 C H o w t o P r o g ra m 2 1 1 9 9 4 c h t p 2 . j p g $ 4 9 .9 5

0 1 3 1 1 8 0 4 3 6 C H o w t o P r o g ra m 1 1 1 9 9 2 c h t p . j p g $ 6 9 .9 5

Fig . 1 9 .1 0 D a t a f ro m t h e T i t l e s t a b le o f B o o k s .

Fig. 19.10 part 3

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The Books DatabaseThe Books Database

Entity-relationship diagram for the Book database

AuthorISBN

authorID

isbn

Authors

authorID

firstName

lastName

Publishers

publisherID

publisherName

Titles

isbn

titleeditionNumber

copyright

publisherIDimageFile

price

1

¥

¥

¥11

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Relational Database QueriesRelational Database QueriesRelational Database Queries

QueriesQueries : return a new result setBased upon relationalrelational algebraalgebra

Uses 3 operations to build a new relation (a result-set)ProjectionProjection, selectionselection, and joinjoin

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What is SQL?What is SQL?

Structured Query Language (SQLSQL)Keywords and rules used to implement relational algebra operations

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SQL KeywordsSQL Keywords

SQL keyword Description SELECT Selects (retrieves) fields from one or more tables.

FROM Specifies tables from which to get fields or delete records. Required in every SELECT and DELETE statement.

WHERE Specifies criteria that determine the rows to be retrieved. INNER JOIN Joins records from multiple tables to produce a single set of records. GROUP BY Specifies criteria for grouping records. ORDER BY Specifies criteria for ordering records. INSERT Inserts data into a specified table. UPDATE Updates data in a specified table. DELETE Deletes data from a specified table.

Fig. 19.12 SQL query keywords.

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Basic Select QueryBasic Select Query

Extracts information from one or more tables in a databaseFormat:

Basic: select * from tableselect * from table--namenameExample: select * from authorsselect * from authors* means "extract all columns"

To get a projection (specific columns), use a list:select select firstnamefirstname, , lastnamelastname from authorsfrom authorsColumn, table names may be case sensitiveSQL keywords should not be case sensitive

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Basic Basic SelectSelect QueryQuery

authorID lastName authorID lastName 1 Deitel 8 M cPhie

2 Deitel 9 Yaeger

3 Nieto 10 Zlatkina

4 Steinbuhler 12 W iederm ann

5 Santry 12 Liperi

6 Lin 13 Listfield 7 Sadhu

Fig . 19.13 authorID a n d lastName fro m th e Authors ta b le .

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WhereWhere ClauseClause

Used to specify certain criteria in a queryBasic form:

SELECT * FROM tableName WHERE criteriaExample:

SELECT * FROM Titles WHERE copyright > 1999Can use LIKE clause

Used for pattern matchingUses wildcards

*: zero or more characters take its place?: exactly one character takes its place

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PatternPattern--matching with Wherematching with Where

Can use likelike clause for string pattern matchingUses wildcards

%: zero or more characters take its place (*)_: exactly one character takes its place (?)

Examples:Select * from authors where Select * from authors where firstnamefirstname like '_e%'like '_e%'Select * from authors where Select * from authors where lastnamelastname like 'D%'like 'D%'

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WHEREWHERE ClauseClauseT i t l e e d i t i o n N u m b e r c o p y r i g h t

I n t e r n e t a n d W o r l d W i d e W e b H o w to P r o g r a m 2 2 0 0 2

J a v a H o w t o P r o g r a m 4 2 0 0 2

T h e C o m p l e t e J a v a T r a i n i n g C o u r s e 4 2 0 0 2

T h e C o m p l e t e e - B u s i n e s s & e - C o m m e r c e P r o g r a m m i n g T r a i n i n g C o u r s e

1 2 0 0 1

T h e C o m p l e t e I n t e r n e t & W o r l d W i d e W e b P r o g r a m m i n g T r a i n in g C o u r s e

2 2 0 0 1

T h e C o m p l e t e P e r l T r a i n in g C o u r s e 1 2 0 0 1 T h e C o m p l e t e X M L P r o g r a m m i n g T r a i n i n g C o u r s e 1 2 0 0 1

C H o w t o P r o g r a m 3 2 0 0 1

C + + H o w to P r o g r a m 3 2 0 0 1

T h e C o m p l e t e C + + T r a i n i n g C o u r s e 3 2 0 0 1

e - B u s i n e s s a n d e - C o m m e r c e H o w t o P r o g r a m 1 2 0 0 1 I n t e r n e t a n d W o r l d W i d e W e b H o w to P r o g r a m 1 2 0 0 0

T h e C o m p l e t e I n t e r n e t a n d W o r l d W i d e W e b P r o g r a m m i n g T r a i n in g C o u r s e

1 2 0 0 0

J a v a H o w t o P r o g r a m ( J a v a 2 ) 3 2 0 0 0

T h e C o m p l e t e J a v a 2 T r a in i n g C o u r s e 3 2 0 0 0

X M L H o w t o P r o g r a m 1 2 0 0 1

P e r l H o w t o P r o g r a m 1 2 0 0 1

A d v a n c e d J a v a 2 P l a t f o r m H o w t o P r o g r a m 1 2 0 0 2 e - B u s i n e s s a n d e - C o m m e r c e f o r M a n a g e r s 1 2 0 0 0

W i r e l e s s I n t e r n e t a n d M o b i l e B u s i n e s s H o w t o P r o g r a m 1 2 0 0 1

C # H o w T o P r o g r a m 1 2 0 0 2

P y t h o n H o w t o P r o g r a m 1 2 0 0 2 V i s u a l B a s i c . N E T H o w to P r o g r a m 2 2 0 0 2

Fig . 1 9 . 1 4 Tit le s w i t h c o p y r ig h t s a f t e r 1 9 9 9 f r o m t a b le T i t l e s .

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WHEREWHERE ClauseClause

authorID firstName lastName 1 Harvey Deitel

2 Paul Deitel

Fig. 19.15 Authors from the Authors table whose last names start with D.

authorID firstName lastName 3 Tem Nieto

6 Ted Lin

11 Ben Wiedermann

12 Jonathan Liperi

13 Jeffrey Listfield Fig. 19.16 Authors from table Authors whose last names contain i as the

second letter.

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Sorting the ResultsSorting the Results

SQL queries return their data in indeterminate orderSame query may return rows in different order each time

Use the order by clause to arrange results of a queryCan be ascending (asc) or descending (desc) order

Examples:select * from authors order by select * from authors order by lastnamelastname descdescselect * from authors select * from authors

order by order by lastnamelastname, , firstnamefirstname ascasc

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ORDER BYORDER BY ClauseClause

Used to arrange results of a queryCan be ascending or descending order

Uses ASC and DESC respectively

Example:SELECT authorID FROM Authors ORDER BY authorID ASC

Can be used to sort by multiple fields

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ORDER BYORDER BY ClauseClauseauthorID firstName lastName 2 Paul Deitel

1 Harvey Deitel

6 Ted Lin

12 Jonathan Liperi


8 David McPhie 3 Tem Nieto

7 Praveen Sadhu

5 Sean Santry

4 Kate Steinbuhler 11 Ben Wiedermann

9 Cheryl Yaeger

10 Marina Zlatkina Fig. 19.17 Authors from table Authors in ascending order by lastName.

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ORDER BYORDER BY ClauseClauseauthorID firstName lastName 10 Marina Zlatkina

9 Cheryl Yaeger

11 Ben Wiedermann

4 Kate Steinbuhler

5 Sean Santry

7 Praveen Sadhu 3 Tem Nieto

8 David McPhie


12 Jonathan Liperi

6 Ted Lin 2 Paul Deitel

1 Harvey Deitel Fig. 19.18 Authors from table Authors in descending order by lastName.

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ORDER BYORDER BY ClauseClauseauthorID firstName lastName 1 Harvey Deitel

2 Paul Deitel

6 Ted Lin

12 Jonathan Liperi


8 David McPhie 3 Tem Nieto

7 Praveen Sadhu

5 Sean Santry

4 Kate Steinbuhler

11 Ben Wiedermann 9 Cheryl Yaeger

10 Marina Zlatkina Fig. 19.19 Authors from table Authors in ascending order by lastName and

by firstName.

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ORDER BYORDER BY ClauseClausei s b n t i t l e e d i t i o n -

N u m b e r c o p y -r i g h t

p r i c e

0 1 3 0 8 9 5 6 0 1 A d v a n c e d J a v a 2 P l a t f o r m H o w t o P r o g r a m

1 2 0 0 2 $ 6 9 . 9 5

0 1 3 1 1 8 0 4 3 6 C H o w t o P r o g r a m 1 1 9 9 2 $ 6 9 . 9 5

0 1 3 0 8 9 5 7 2 5 C H o w t o P r o g r a m 3 2 0 0 1 $ 6 9 . 9 5

0 1 3 2 2 6 1 1 9 7 C H o w t o P r o g r a m 2 1 9 9 4 $ 4 9 . 9 5

0 1 3 0 6 2 2 2 1 4 C # H o w T o P r o g r a m 1 2 0 0 2 $ 6 9 . 9 5

0 1 3 5 2 8 9 1 0 6 C + + H o w t o P r o g r a m 2 1 9 9 8 $ 4 9 . 9 5 0 1 3 1 1 7 3 3 4 0 C + + H o w t o P r o g r a m 1 1 9 9 4 $ 6 9 . 9 5

0 1 3 0 8 9 5 7 1 7 C + + H o w t o P r o g r a m 3 2 0 0 1 $ 6 9 . 9 5

0 1 3 0 2 8 4 1 9 X e - B u s i n e s s a n d e - C o m m e r c e H o w t o P r o g r a m

1 2 0 0 1 $ 6 9 . 9 5


2 2 0 0 2 $ 6 9 . 9 5


1 2 0 0 0 $ 6 9 . 9 5

0 1 3 0 3 4 1 5 1 7 J a v a H o w t o P r o g r a m 4 2 0 0 2 $ 6 9 . 9 5

0 1 3 6 3 2 5 8 9 0 J a v a H o w t o P r o g r a m 1 1 9 9 8 $ 4 9 . 9 5 0 1 3 0 2 8 4 1 8 1 P e r l H o w t o P r o g r a m 1 2 0 0 1 $ 6 9 . 9 5

0 1 3 0 9 2 3 6 1 3 P y t h o n H o w t o P r o g r a m 1 2 0 0 2 $ 6 9 . 9 5

0 1 3 0 2 9 3 6 3 6 V i s u a l B a s i c . N E T H o w t o P r o g r a m

2 2 0 0 2 $ 6 9 . 9 5

0 1 3 4 5 6 9 5 5 5 V i s u a l B a s i c 6 H o w t o P r o g r a m

1 1 9 9 9 $ 6 9 . 9 5

0 1 3 0 6 2 2 2 6 5 W i r e l e s s I n t e r n e t a n d M o b i l e B u s i n e s s H o w t o P r o g r a m

1 2 0 0 1 $ 6 9 . 9 5

0 1 3 0 2 8 4 1 7 3 X M L H o w t o P r o g r a m 1 2 0 0 1 $ 6 9 . 9 5

F ig . 1 9 . 2 0 B o o k s f r o m t a b le T i t l e s w h o se t i t le s e n d w it h H o w t o P r o g r a m i n a sc e n d in g o rd e r b y t i t l e .

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Merging Data from Multiple Tables: Merging Data from Multiple Tables: INNER JOININNER JOIN

Merges records from multiple tables into a single recordTests for matching values in a common field

General Form:select * from table1 select * from table1 inner join table 2 on table1.field = table2.fieldinner join table 2 on table1.field = table2.field

Example:select select firstnamefirstname, , isbnisbn from from authors inner join authors inner join authorISBNauthorISBNon on authors.authorIDauthors.authorID = = authorsISBN.authorIDauthorsISBN.authorID

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Merging Data from Multiple Tables: Merging Data from Multiple Tables: INNER JOININNER JOIN

fir s t N a m e l a s t N a m e i s b n f i r s t N a m e l a s t N a m e i s b n H a r v e y D e i te l 0 1 3 0 8 9 5 6 0 1 H a r v e y D e i te l 0 1 3 0 8 2 9 2 9 3

H a r v e y D e i te l 0 1 3 0 2 8 4 1 8 1 H a r v e y D e i te l 0 1 3 4 5 6 9 5 5 5

H a r v e y D e i te l 0 1 3 0 2 8 4 1 7 3 H a r v e y D e i te l 0 1 3 0 8 2 9 2 7 7

H a r v e y D e i te l 0 1 3 0 8 5 2 4 7 3 P a u l D e i te l 0 1 3 0 1 2 5 0 7 5


H a r v e y D e i te l 0 1 3 0 8 5 6 1 1 8 P a u l D e i te l 0 1 3 0 1 6 1 4 3 8 H a r v e y D e i te l 0 1 3 0 1 6 1 4 3 8 P a u l D e i te l 0 1 3 0 2 8 4 1 9 x

H a r v e y D e i te l 0 1 3 0 2 8 4 1 9 x P a u l D e i te l 0 1 3 9 1 6 3 0 5 0


H a r v e y D e i te l 0 1 3 5 2 8 9 1 0 6 P a u l D e i te l 0 1 3 5 2 8 9 1 0 6 H a r v e y D e i te l 0 1 3 0 8 9 5 7 1 7 P a u l D e i te l 0 1 3 0 8 9 5 7 1 7



H a r v e y D e i te l 0 1 3 0 1 2 5 0 7 5 T e m N ie to 0 1 3 0 2 8 4 1 8 1

P a u l D e i te l 0 1 3 0 2 8 4 1 8 1 T e m N ie to 0 1 3 0 2 8 4 1 7 3 P a u l D e i te l 0 1 3 0 2 8 4 1 7 3 T e m N ie to 0 1 3 0 8 2 9 2 9 3

P a u l D e i te l 0 1 3 0 8 2 9 2 9 3 T e m N ie to 0 1 3 4 5 6 9 5 5 5



P a u l D e i te l 0 1 3 0 8 5 2 4 7 3 T e m N ie to 0 1 3 0 2 8 4 1 9 x P a u l D e i te l 0 1 3 8 9 9 3 9 4 7

Fig . 1 9 .2 1 A u t h o rs f ro m t a b le A u t h o r s a n d ISBN n u m b e rs o f t h e a u t h o rs’ b o o k s, so rt e d in a sc e n d in g o rd e r b y l a s t N a m e a n d f i r s t N a m e .

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Joining Data from Tables Authors, Joining Data from Tables Authors, AuthorISBNAuthorISBN, Titles and Publishers, Titles and Publishers

Tables produced by INNER JOIN can be used as arguments for another INNER JOIN

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Joining Data from Tables Joining Data from Tables AuthorsAuthors, , AuthorISBNAuthorISBN, , TitlesTitles and and PublishersPublishers

1 SELECT Titles.title, Titles.isbn, Authors.firstName, 2 Authors.lastName, Titles.copyright, 3 Publishers.publisherName4 FROM5 ( Publishers INNER JOIN Titles 6 ON Publishers.publisherID = Titles.publisherID ) 7 INNER JOIN8 ( Authors INNER JOIN AuthorISBN 9 ON Authors.authorID = AuthorISBN.authorID ) 10 ON Titles.isbn = AuthorISBN.isbn11 ORDER BY Titles.title

Fig. 19.22 TitleAuthor query of Books database.

Join Publishers and Titles tables if the publisherID matches

Join Authors and AuthorISBN if authorID matches

Join two created tables if titlesISBN matches authorsISBN

Sort new table by title

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Title i s b n f i r s t -N a m e

l a s t -N a m e

c o p y -r i g h t

p u b l i s h e r -N a m e

A d v a n c e d Ja v a 2 P la tfo rm H o w to P ro g ra m

0 1 3 0 8 9 5 6 0 1 P a u l D e ite l 2 0 0 2 P re n tic e H a ll


0 1 3 0 8 9 5 6 0 1 H a rv e y D e ite l 2 0 0 2 P re n tic e H a ll


0 1 3 0 8 9 5 6 0 1 S e a n S a n tr y 2 0 0 2 P re n tic e H a ll

C H o w to P ro g ra m 0 1 3 1 1 8 0 4 3 6 H a rv e y D e ite l 1 9 9 2 P re n tic e H a ll

C H o w to P ro g ra m 0 1 3 1 1 8 0 4 3 6 P a u l D e ite l 1 9 9 2 P re n tic e H a ll





C # H o w T o P ro g ra m 0 1 3 0 6 2 2 2 1 4 T e m N ie to 2 0 0 2 P re n tic e H a ll

C # H o w T o P ro g ra m 0 1 3 0 6 2 2 2 1 4 P a u l D e ite l 2 0 0 2 P re n tic e H a ll

C # H o w T o P ro g ra m 0 1 3 0 6 2 2 2 1 4 J e ffre y L is t fie ld 2 0 0 2 P re n tic e H a ll

C # H o w T o P ro g ra m 0 1 3 0 6 2 2 2 1 4 C h e r yl Y a e g e r 2 0 0 2 P re n tic e H a ll

C # H o w T o P ro g ra m 0 1 3 0 6 2 2 2 1 4 M a r in a Z la tk in a 2 0 0 2 P re n tic e H a ll

C # H o w T o P ro g ra m 0 1 3 0 6 2 2 2 1 4 H a rv e y D e ite l 2 0 0 2 P re n tic e H a ll

C + + H o w to P ro g ra m 0 1 3 0 8 9 5 7 1 7 P a u l D e ite l 2 0 0 1 P re n tic e H a ll

Fig. 19.23 part 1

45


C++ How to Program 0130895717 Harvey Deitel 2001 Prentice Hall

C++ How to Program 0131173340 Paul Deitel 1994 Prentice Hall



C++ How to Program 0135289106 Paul Deitel 1998 Prentice Hall

e-Business and e-Commerce for Managers

0130323640 Harvey Deitel 2000 Prentice Hall


0130323640 Kate Steinbuhler

2000 Prentice Hall


0130323640 Paul Deitel 2000 Prentice Hall

e-Business and e-Commerce How to Program

013028419X Harvey Deitel 2001 Prentice Hall


013028419X Paul Deitel 2001 Prentice Hall


013028419X Tem Nieto 2001 Prentice Hall

Fig . 19.23 Po rt io n o f the re su lt se t p ro d uc e d b y the q ue ry in Fig . 19.22.

Fig. 19.23 part 2

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The Selection OperationThe Selection Operation

The selection operation is accomplished using wherewhereBasic form:

select * from tableselect * from table--name where criterianame where criteriaExample:

select * from titles where copyright > 1999select * from titles where copyright > 1999Make sure String criteria are inside single quotesCan use expected relational operators

select * from authors where select * from authors where firstnamefirstname > 'B'> 'B'

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SQL and Relational Operators with the Where ClauseSQL and Relational Operators with the Where Clause

SQL supports several relational operators for writing conditional expressions

Operator Meaning

> Greater than

< Less than

>= Greater than or equal to

<= Less than or equal to

= Equal to

<> Not equal to

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SQL String FunctionsSQL String Functions

SQL keywords and clauses are not case-sensitive. But, string comparison are.‘Denim Jeans’, ‘denim jeans’, and ‘Denim jeans’ are considered three different string literals The following three SQL statements will generate three different results:

SELECT * FROM Product WHERE Description = ‘Denim Jeans’SELECT * FROM Product WHERE Description = ‘denim jeans’SELECT * FROM Product WHERE Description = ‘Denim jeans’

You can use the Lower() or Upper() string function before performing the comparison

SELECT * FROM Product WHERE Lower(Description) = ‘denim jeans’SELECT * FROM Product WHERE Upper(Description) = ‘DENIM JEANS’

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Using the LIKE OperatorUsing the LIKE Operator

The LIKE operator allows you to do a search based on a pattern rather than specifying exactly what is desired

“Oxford Cloth Shirt” and “Poplin Shirt” both contains the string “Shirt”Use the string “Shirt” as the pattern with the wildcard character %% represents any sequence of zero or more characters

SELECT * FROM Product WHERE Description LIKE ‘%Shirt%’SELECT * FROM Product WHERE Description LIKE ‘Chino%’SELECT * FROM Product WHERE Description LIKE ‘%jeans’

The underscore (_) wildcard character represents a single character. To search for all rows in which Product_Number begins with “2”, followed by any one character, followed by “-0”, followed by any one character, use

SELECT * FROM Product WHERE Product_Number LIKE ‘2_-0_’

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Sorting the Results of a Select QuerySorting the Results of a Select Query

To sort the results of a SELECT query, use the ORDER BY clauseSELECT * FROM Product ORDER BY PriceSELECT * FROM Product WHERE Price > 20.00 ORDER BY Price

The results will be sorted in ascending orderTo sort in descending order, use the Desc operator

SELECT * FROM Product ORDER BY Price DescSELECT * FROM Product WHERE Price > 20.00 ORDER BY Price Desc

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Insert StatementInsert Statement

Inserts a new record into a tableGeneral form:

insert into tableinsert into table--name(fieldname1, fieldname2,...) name(fieldname1, fieldname2,...) values(value1, value2)values(value1, value2)

Example:insert into insert into authors(authorIDauthors(authorID, , lastnamelastname, , firstnamefirstname))values(15, 'Gilbert', 'Steve')values(15, 'Gilbert', 'Steve')

Values must match field names in order and type

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INSERTINSERT StatementStatementauthorID firstName lastName 1 Harvey Deitel

2 Paul Deitel

3 Tem Nieto

4 Kate Steinbuhler

5 Sean Santry

6 Ted Lin 7 Praveen Sadhu

8 David McPhie

9 Cheryl Yaeger

10 Marina Zlatkina 11 Ben Wiedermann

12 Jonathan Liperi


14 Sue Smith Fig. 19.24 Authors a fte r a n INSERT op era tion to a d d a rec ord .

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The Update StatementThe Update Statement

Modifies data in a tableGeneral Form:

update tableupdate table--name set field1=value1 name set field1=value1 where criteriawhere criteria

Example:update authors set update authors set firstnamefirstname='Stephen' ='Stephen' where where lastnamelastname='Gilbert' and ='Gilbert' and firstnamefirstname='Steve'='Steve'

What happens if you violate an integrity rule?

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UPDATEUPDATE StatementStatementauthorID firstName lastName 1 Harvey Deitel

2 Paul Deitel

3 Tem Nieto

4 Kate Steinbuhler

5 Sean Santry


8 David McPhie

9 Cheryl Yaeger

10 Marina Zlatkina

11 Ben Wiedermann 12 Jonathan Liperi


14 Sue Jones Fig. 19.25 Ta b le Authors a fte r a n UPDATE op era tion to c ha nge a rec ord .

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The Delete StatementThe Delete Statement

Removes data from a tableGeneral Form:

delete from tabledelete from table--name where criterianame where criteriaDon't forget the criteria!!!

Example:delete from authors where delete from authors where lastnamelastname='Gilbert'='Gilbert'

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DELETEDELETE StatementStatementauthorID firstName lastName 1 Harvey Deitel

2 Paul Deitel

3 Tem Nieto

4 Kate Steinbuhler

5 Sean Santry


8 David McPhie

9 Cheryl Yaeger

10 Marina Zlatkina

11 Ben Wiedermann 12 Jonathan Liperi

13 Jeffrey Listfield Fig. 19.26 Table Authors after a DELETE operation to remove a record .

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SQL Math FunctionsSQL Math Functions

SQL provides several functions for performing calculationsAvg(Column): calculates the average value in a particular column

SELECT Avg(Price) FROM Product

Sum(Column): calculates the sum of a column’s valuesSELECT Sum(Price) FROM Product

Min(Column): finds the minimum value of a column.SELECT Min(Price) FROM Product

Max(Column): finds the maximum value of a columnSELECT Max(Price) FROM Product

Count(Column): returns the number of values of the specified columnSELECT Count(Price) FROM Product

To determine the number of rows in a table, use:SELECT Count(*) FROM Product

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Creating a Database in Visual StudioCreating a Database in Visual Studio

A .NET application uses several components, arranged in layers, to connect to a database

Data Source – a source of data with which the application can workTable Adapter – connects to a data source and retrieves data from a table in a data sourceDataset – gets a copy of a table from the table adapter and keeps the copy of the table in memoryBinding Source – a component that can connect user interface controls directly to a dataset

Application

Binding Source

Dataset

Table Adapter

Data Source

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Creating A ServerCreating A Server--Based DatabaseBased Database

Visual Studio provides wizards that make it easy to create and configure the database

The Add New Item window provides a Service-based Database option for creating an empty SQL Server databaseThe default name of the SQL Server database is Database1.mdfThis book uses SQL Server database as examples

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The Database File’s LocationThe Database File’s Location

When you use Visual Studio to create a SQL server database, the database file will be created in the project’s folder

The “project’s folder” is where the Form1.cs, Form1.Designer.cs, and Program.cs files are storedThe file extension is .mdf. For example, Phonelist.mdf.The server will also create a file that ends with the .LDF extension. For example, Phonelist_log.LDF.

This is a transaction log file used to keep a log of all the operations that you perform on the database

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