1-SQL-Basics.ppt

8/9/2019 1-SQL-Basics.ppt

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Database Access using SQL

A basic introduction

James Brucker


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Database Management System

Database: astructured, self-describing collectionof data.

Control access tothe database.

• authentication

• enforcepermissions

• data integrity

• access services

Databas

eManage

r

User

Interface communication protocol

SELECT * FROMcity WHERE nameLIKE Ban%

Client


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Client - Server Databases

Database Server is a separate process on a host

Clients can be on any machine

Many programs may be clients using a standard A!"

Server mysqld

#mys$l# utility

Java App%JDBC client

&'cel client

Server sideClient side

server controlsaccess todatabase


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"nstall Client So(t)are

*or this lab+ you )ill access MySQL server on thenet)ork All you need is a client application ,ou dontneed to run a MySQL server on your computer

Client .ools

mysql!"r#$enc&'l())y!in+,)msi

"r -se "lder ./I T""ls0

mysql&-it""ls()1)2!in+,)msi

*rom/ secpekuacth0do)nload0mys$l


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Add MySQL #bin# to your !ath

.his is so you can run the #mys$l# command line

1n 2indo)s/

3 4ight-click My Computer

5 Choose !roperties

6 Click # Advanced#

7 Click #&nvironment 8ariables#

9 &dit !A.: variable and add/

C/;2indo)s;blah3C045r"&ram Files4MySql4$in


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&'ercise


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&'ercise

Connect to MySQL server on host #secpekuacth#

user/ student pass)ord/ student

2hat MySQL version is the server >

d"s6 mysql se)c'e)#-)ac)t - st-dent '

Enter 'ass!"rd0 nisit

mysql6 SELECT versi"n>?3


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Structure o( a Database

A database system may contain many databases &ach database is composed o( schema and tables

sql6 /SE $an#3

sql6SHOW ta$les3@@

A Ta$lesin$an# A@@A acc"-nts AA clients A

@@

sql6 SHOW data$ases3

@@A 9ata$ase A

@@

A mysql A

A test A

A $an# AA !"rld A

@@

MySQL only shows databases thata user has permission to access.


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A Database Structure

Database

Schema

.able(ield3/ t3(ield5/ t5(ield6/ t6

inde'es

Schema


inde'es


inde'es


inde'es

A database contains schema+)hich describe theorgani?ation o( the database

A schema can contain/

tables - containing data

inde' (iles - (or (ast lookup o(data

stored procedures+constraints+ triggers+ andmore


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Contents o( a .able

A table contains the actual data in records @ro)s A record is composed o( (ields @columns

&ach record contains one set o( data values

@@@@@@

A I9 A ame A CC"de A 9istrict A 5"'-latn

@@@+@A ++,: A Ban"# A THD A Ban"# A ;+,:128 A

A ++,1 A "nta$-ri A THD A "nta$-ri A ,,1:: AA ++,+ A Cian& Mai A THD A Cian& Mai A 1211:: A@@@@@@

records

(rows)

fields (columns)


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ey (ield (or "denti(ying 4o)s

A table contains a primary key that uni$uely identi(iesa ro) o( data

&ach record must have a distinct value o( primary key

.he primary key is used to relate @ oin tables

@@@@@@

A I9 A ame A CC"de A 9istrict A 5"'-latn

@@@+@A ++,: A Ban"# A THD A Ban"# A ;+,:128 AA ++,1 A "nta$-ri A THD A "nta$-ri A ,,1:: AA ++,+ A Cian& Mai A THD A Cian& Mai A 1211:: A@@@@@@

ID is the primary key in ity table.


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Structure o( a .able

&very (ield has/

a name

a data type and length

.o vie) the structure o( a table use/DESCRIBE tablename

sql6 9ESCRIBE City3@@@@@@@A Field A Ty'e A -llA Key A 9e=a-lt A Etra A@@@@@@@A I9 A int>11? A O A 5RI A A a-t"increment AA ame A car>+(? A O A A A AA C"-ntryC"de A car>+? A O A A A AA 9istrict A car>,:? A O A A A AA 5"'-lati"n A int>11? A O A A : A A

@@@@@@@


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Structure o( a .able

#SHOW columns FROM tablename#

sho)s the same in(ormation

sql6 SHOW c"l-mns FROM City3@@@@@@@A Field A Ty'e A -llA Key A 9e=a-lt A Etra A@@@@@@@A I9 A int>11? A O A 5RI A A a-t"increment AA ame A car>+(? A O A A A AA C"-ntryC"de A car>+? A O A A A AA 9istrict A car>,:? A O A A A AA 5"'-lati"n A int>11? A O A A : A A@@@@@@@

!ields may have a defaultvalue to use if a value is

not assi"ned e#plicitly.


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Structured Query Language

Structured Query Language @SQL is the standardlanguage (or accessing in(ormation a database

SQL is case-insensitive and (ree (ormat

&nter commands interactively or in a script (ile

SQL statements can use multiple lines end each statement )ith a semi-colon ;

sql> /SE !"rld3

database changed.

sql> SHOW ta$les3

sql> SHOW c"l-mns FROM city3

sql> 9ECRIBE c"-ntry3

!"# statements end $ith semi-colon.


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&'ercise

3 Connect to MySQL server on host #secpekuacth#

user/ student pass)ord/ nisit

5 2hat databases are on the server>

6 2hat tables are in the !"rld database>

d"s6 mysql se)c'e)#-)ac)t - st-dent '

Enter 'ass!"rd0 nisit

mysql6 SHOW data$ases3

mysql6 /SE !"rld3

mysql6 SHOW ta$les3


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mysql6 SHOW ta$les

FROM

!"rld

3

&'ercise

%o semi-colon.

1mit the semi-colon 2hat happens> &nter a command on several lines


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D&SC4"B&

D&SC4"B& sho)s the structure o( a table same as #S:12 columns *41M tablename#

sql6 9ESCRIBE city3@@@@@@@A Field A Ty'e A -llA Key A 9e=a-lt A Etra A@@@@@@@A I9 A int>11? A O A 5RI A A a-t"increment AA ame A car>+(? A O A A A A

A C"-ntryC"de A car>+? A O A A A AA 9istrict A car>,:? A O A A A AA 5"'-lati"n A int>11? A O A A : A A@@@@@@@


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&'ercise

*or the !"rld database/

)hat (ields does the Country table have>

)hat in(ormation is in the (ields>

)hich (ields contain strings> @char or varchar

)hich (ields contain (loating point values> )hat is the primary key o( the Country table>


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&'ercise/ Case Sensitivity

"s SQL case sensitive>

Are names o( databases and tables case sensitive>

mysql6 9ESCRIBE city 3

mysql6 descri$e city 3

mysql6 -se !"rld3

mysql6 -se WORL93

mysql6 descri$e city3

mysql6 descri$e City3


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&'ercise/ 1-1 Analogy o( a .able>

Database Object Oriented

table

record @ro)

(ields @columns

@@@@@

A I9 A ame A 9istrict A 5"'-la))

@@@+@

A ++,: A Ban"# A Ban"# A ;+,:128 AA ++,1 A "nta$-ri A "nta$-ri A ,,1:: AA ++,+ A Cian& Mai A Cian& Mai A 1211:: A@@@@@

fields (columns)

records (rows)


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Quali(ying Eames

SQL uses ## to $uali(y elements o( a hierarchy

ust like most 1-1 languages

Wold.cit! #city# table in 2orld db

cit!.namename (ield in city table

Wold.cit!.name (ully $uali(ied name

sql6 9ESCRIBE W"rld)c"-ntry3)))sql6 SELECT c"-ntry)name =r"m c"-ntry3


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7 Basic Database 1perations

.he 7 most common operations/

S&L&C. $uery @search the data

"ES&4. add ne) records to a table@s


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Querying Data in a .able

S&L&C. displays (ield values (rom a table/

SELECT =ield1< =ield,< =ield+ FROM ta$le 3

displays ALL ro)s (rom the table

use L"M". number to limit ho) many results

sql6 SELECT acc"-nt-m$er< $alance FROM acc"-nts3

@@@@@

A acc"-nt-m$er A acc"-ntame A clientI9 A $alance A@@@@@

A 1111111+ A 5)Watana'"n& A ::::1::1 A +::::: A

A 11111118 A C5E F-nd A ::::1::, A 1G8:::: A

@@@@@


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S&L&C. statement )ith F

Display values (or all (ields in table/

SELECT * FROM ta$lename 3

sql6 SELECT * =r"m acc"-nts3

@@@@@

A acc"-nt-m$er A acc"-ntame A clientI9 A $alance A

@@@@@

A 1111111+ A 5)Watana'"n& A ::::1::1 A +::::: AA 11111118 A C5E F-nd A ::::1::, A 1G8:::: A

@@@@@


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Quali(ying S&L&C.

Select columns (rom a table that match some criteria/

SELECT =ield1< =ield,< =ield+

FROM ta$le

WHERE c"nditi"nOR9ER B =ield1


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Strings in SQL


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&'ercises

3 2hat are the (irst 6 cities in the database>5 2hat are the 6 most populous countries in the )orld>

6 2hat is the smallest country in the )orld> :o) big>


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&'ercises (or .hailand

3 2hat is the country code (or .hailand>S&L&C. F (rom WHERE name Tailand

5 List the cities in .hailand+ sorted by largest population

to smallest


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2:&4& conditions

name Ban"# e$uality testname LIKE Ban&% pattern match

'"'-lati"n 6 1:::::

'"'-lati"n (:::::&n' 6 :

relations

GH is not e$uals

&rade I >D


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&'ercise )ith 2:&4& I 14D&4

3 2hat is the most populous country in &urope> use WHERE c"ntinent )))

5 2hat countries have name beginning )ith >

6 "n .hailand )hat cities have names like Ban


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Count *unction

Select can be used )ith (unctions+ such as C1*? FROM acc"-nts WHERE $alance:3

sql6 SELECT CO/T>*? =r"m acc"-nts3@@

A c"-nt>*? A

@@

A 8 A

@@

sql6 SELECT CO/T>*? =r"m acc"-nts

WHERE $alance 6 1::::::3


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&'ercise

3 :o) many countries are in the database>

5 :o) many cities are in China>

6 :o) many countries are in &urope>


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1ther *unctions in SQL

*unctions can have arguments+ ust like C+ Java+ etc

S/M > expression ?

MDN> expression ?

MI> expression ?CO/T> e'ressi"n ?

sql6 SELECT MDN>S-r=aceDrea? FROM c"-ntry3

1:2(8::):: >sq)#m)?

241E=/ This will NOT find the largest country!

sql6 SELECT MDN>S-r=aceDrea?


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S&L&C. (unctions

:o) many people are in the )orld>

SELECT S/M >5"'-lati"n? FROM C"-ntry3

:o) big is the largest country in Asia>

SELECT MDN>S-r=aceDrea?

FROM C"-ntry WHERE c"ntinentDsia3

2hat is the version o( MySQL>

SELECT versi"n>?3


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&'ercise

3 2hat is the total =E! o( the entire )orld>

sql> SE#EC$ sum%&'() FROM count!

3 2hat are the richest countries @=E! per person in the

)orld>

sql> SE#EC$ name* &'(+,o,ulation

FROM count!

ORDER B" &'(+,o,ulation DESC

#IMI$ -/

2hat are the most cro)ded countries @people per sur(acearea in Asia>


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&'ercise (or *unctions

:arder /

2hat are total population and total =E! o( eachcontinent>

:int/ use .RO/5 B c"ntinent


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&'pressions and Arithmetic

,ou can use expressions in SQL

Arithmetic/ @ * % sqrt>?

=rouping/ > ?

String ops/ s-$strin&> ?< -''er>?< len&t> ?

&'ample/ display GNP per person for each country

sql6 SELECT name< &n''"'-lati"n DS ca'ita&n'

FROM c"-ntry

OR9ER B ca'ita&n' 9ESC3

*alue of +, is in millions of &S Dollars.

-ow can you show per capita +, in dollars'''

alias


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&'ercise

3 2hat countries are the richest> !oorest>

Sho) the GNP per capita @in

Cro)ding re(ers to population per surface area


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2ildcards to match patterns

!attern matches/ =ield LIKE 'attern

SELECT * FROM city

WHERE name LIKE Ban%3

K means #match anything#


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Adding Ee) 4ecords

"ES&4. adds a ne) record to a table

ISERT ITO ta$le

7DL/ES > data1< data,< )))?3

sql6 ISERT ITO Dcc"-nts 7DL/ES

>,,,,,,,,< Dm'le Ric< :::::::1 1:::::::?3

P-ery OK< 1 r"! a==ected )

@@@@@

A acc"-nt-m$er A acc"-ntame A clientI9 A $alance A@@@@@

A ,,,,,,,, A Dm'le Ric A :::::::1 A1::::::: A

@@@@@


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"ES&4. into columns by name

ISERT ITO ta$le >=ield1< =ield,< )))?

7DL/ES > data1< data,< )))?3

sql6 ISERT ITO Dcc"-nts

>acc"-nt-m$er< $alance< acc"-ntame?

7DL/ES

>,,,,,,,,< 1:::::::< Dm'le Ric?3


@@@@@A acc"-nt-m$er A acc"-ntame A clientI9 A $alance A

@@@@@

A ,::::::: A Dm'le Ric A A1::::::: A

@@@@@


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&'ercise

Add your home to)n to the City table

or+ add another city to the City table

sql6 ISERT ITO city

>name< c"-ntryC"de< district< '"'-lati"n?

7DL/ES

>Ban&saen< THD< C"n$-ri< +::::?3P-ery OK< 1 r"! a==ected )

he ID field has a /ualifier 0&12I,%3M3,.

(see4 D3S%I53 ity)

his means MySQL will assi"n the ID value itself.


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&'ercise

8ie) the City data that you ust added

Correct any errors using

sql6 SELECT * FROM City

WHERE City)name Ban&saen3

sql6 /59DTE City SET '"'-lati"n ++:::

WHERE City)name Ban&saen3



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2arning/ "ES&4. is immediate

Change occurs immediately

unless you are using transactions

Duplicate data is possible


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6 )ays to add data to a table

3 "ES&4. command @boring

5 2rite "ES&4. commands in a te't (ile and #source#the (ile @better

sql6 SO/RCE mydata)sql

6 "M!14. command @synta' depends on DBMS/

sql6 LOD9 9DTD IFILE filename ITO table )))


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Copying Data Bet)een .ables

Suppose )e have another table named Ee)Accts Ee)Accts has accountEumber+ accountEame+

ISERT ITO table >=ield1< =ield,< )))?

SELECT =ield1< =ield,< =ield+

FROM other_table

WHERE condition3

sql6 ISERT ITO Dcc"-nts

SELECT * FROM e!Dcc"-nts

WHERE acc"-nt-m$er OT /LL3


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Change values in one or more records/

/59DTE ta$le

SET =ield1val-e1< =ield,val-e, WHERE c"nditi"n3

sql6 /59DTE citySET '"'-lati"n8::::

WHERE nameBan&saen D9 c"-ntryc"deTHD3

P-ery OK< 1 r"! a==ected >:): sec?

A name A c"-ntryc"de A district A '"'-lati"n A@@@@@A 11111111 A THD A C"n$-ri A 8:::: A


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,ou can change multiple columns/

/59DTE ta$le

SET =ield1val-e1< =ield,val-e, WHERE c"nditi"n3

sql6 /59DTE c"-ntrySET '"'-lati"n;G1:::::< &n'+8(;::

WHERE c"deTHD3

P-ery OK< 1 r"! a==ected >:): sec?

&'ample: Update population and (%) of *hailand

!ource: CI+ orld actboo /on the $eb0


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2arning/ dont (orget 2:&4&

Ma#e s-re tat y"-r WHERE cla-se selects"nly rec"rds y"- !ant t" can&eQ

sql6 /59DTE c"-ntry

SET '"'-lati"n;G1:::::< &n'+8(;:: 3

Query 1+ 57 ro)s a((ected @37 sec

han"ed every countryin the database66

1ops6

I for"ot $-3%3 ...


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2arning/

Changes occur immediately @Cant undo )0o transBe Careful! "( you (orget the 2:&4& clause it )ill

change all the ro)s in the table

sql6 /59DTE c"-ntry SET HeadO=StateO$ama3

* O"'sQ I ="r&"t WHERE ))) *@@@@@A C"de A ame A C"ntinent A HeadO=State A@@@@@A DF. A D=&anistan A Dsia A O$ama A

A L9 A eterlands A E-r"'e A O$ama AA DLB A Dl$ania A E-r"'e A O$ama AA 9D A Dl&eria A D=rica A O$ama AA DSM A Dmerican Sam"a A Oceania A O$ama AA D9 A Dnd"rra A E-r"'e A O$ama AA D.O A Dn&"la A D=rica A O$ama A

1bama rules6


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&'ercise


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Deleting 4ecords

D&L&.& one or more records

9ELETE FROM tablename WHERE condition3

&'ample/ Delete all cities )ith ?ero population

sql6 9ELETE FROM City WHERE '"'-lati"n :3

P-ery OK< ( r"!s deleted )


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2arning/ D&L&.& can delete all

D&L&.& a((ects all ro)s that match

9ELETE FROM tablename WHERE condition3

&'ample/ Delete all cities )ith ?ero population

sql6 9ELETE FROM City

WHERE '"'-lati"n :3P-ery OK< ( r"!s deleted )


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Sa(er Delete

*irst S&L&C. the key o( the ro) you )antsql> SELECT id FROM City WHERE nameBan&saen3

;8:,

"( only one match+ then delete using primary key

sql> 9ELETE FROM City WHERE id;8:,3


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4elating .ables

.he po)er o( a relational database is theability to selectively combine data (rommany tables

select data (rom multiple tables by matching values

4elationship can be/

3-to-3 student -H photograph

3-to-many country -H city

many-to-3 city -H country

many-to-many language -H country


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eys

&very table should have a primary key that uni$uely identi(ies each ro)

City

I9 >5K? ameC"-ntryC"de >FK?5"'-lati"n9istrict

C"-ntry

C"de >5K? ameC"ntinentCa'ital)))

C"-ntryC"de

sql6 9ESCRIBE C"-ntry3@@@@@@@A Field A Ty'e A -llA Key A 9e=a-lt A Etra A

@@@@@@@A C"de A car>+? A O A 5RI A A AA ame A car>(,? A O A A A AA ))) A A A A A A


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Joining .ables

4elate or # oin# tables using a condition


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&'ample/ Join Country and City

SELECT C"-ntry)ame< City)ameFROM C"-ntry< City

WHERE C"-ntry)C"de City)C"-ntryC"de D9 C"ntinent S"-t Dmerica3

C"-ntryC"de ameC"ntinentRe&i"n

S-r=aceDrea5"'-lati"n.5L"calameCa'ital

CityI9 ameC"-ntryC"de9istrict

5"'-lati"n

CountryCode N CityCountryCode


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&'ercise/ Cities in Laos

SELECT c")ame< c)ame< c)5"'-lati"n

FROM C"-ntry c"< City c WHERE ))) D9 )))3

List the city names and city populations in Laos


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&'ercise

3 :o) can )e (ind the name o( the capital city (or eachcountry>

C"-ntryC"de >5K?

ameC"ntinentRe&i"nS-r=aceDrea5"'-lati"n.5L"calameCa'ital

CityI9 >5K?

ameC"-ntryC"de9istrict5"'-lati"n


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&'ercise Solution

List the country name and capital city name+ (or allcountries in Asia

SELECT c")name< c)name DS Ca'italCity FROM C"-ntry c"< City c

WHERE )))

D9 ))) 3


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&'ercise

3 "n )hat countries is the .hai language spoken>5 By )hat percentage o( the people>

&'ample/

SELECT CO)name< L)lan&-a&e< L)'ercenta&e

FROM C"-ntry CO< C"-ntryLan&-a&e L WHERE )))

D9 ))) 3


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Ans)er using Aliases

"n )hat countries is Chinese the o((icial language>

SELECT C)name< L)lan&-a&e< L)'ercenta&e

FROM C"-ntry C< C"-ntryLan&-a&e L

WHERE C)c"de L)c"-ntryc"de D9 L)lan&-a&e LIKE %Cinese

D9 isO==icial T3

alias (orCountryLanguageyou can omit table name

)hen there is no ambiguity


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&'ercise

3 2hat countries use &nglish>

14D&4 the results by percentage spoken+ (romlargest to smallest K

5 "n ho) many countries is &nglish the o((iciallanguage>

Harder

6 "n the )orld+ appro'imately ho) many people speak&nglish>

sum@ Cpopulation F Lpercentage 0 3


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J1"E

Joins tables

Many (orms/

"EE&4 J1"E @include only matching columns

1


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&'ample o( a Condition Join

J1"E the CountryLanguage and Language tablesusing the country code/

SELECT CO)ame< L)lan&-a&e< L)'ercenta&e

FROM C"-ntry COOI C"-ntryLan&-a&e L

O CO)c"de L)c"-ntryc"de

WHERE )))3


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Multiple .able Join

,ou can oin many tables at one time/

SELECT CO)name< C)*< L)lan&-a&e

FROM C"-ntry COOI C"-ntryLan&-a&e L

O CO)c"de L)c"-ntryc"de

OI City C

O CO)c"de C)c"-ntryc"de WHERE )))3 * m"re c"nditi"ns *


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More S&L&C. Synta'


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=41

.RO/5 B ))) is used )hen you )ant to apply a(unction @count+ sum+ avg to a group o( ro)s having acommon characteristic

&'ample/ :o) many countries are in each continent>

SELECT c"ntinent< c"-nt>*? FROM c"-ntry

.RO/5 B c"ntinent


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=41

FROM )))

.RO/5 B )))


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Logical operations

14 SELECT * FROM City WHERE

9istrictS"nla OR 9istrictBan"#3

AED

SELECT ame< S-r=aceDrea FROM C"-ntry WHERE

C"ntinent D=rica D9 S-r=aceDrea 6 1::::::3

E1.

SELECT * FROM Dcc"-nts WHERE

OT Dvaila$leBalance :3


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Set operations

"E

SELECT * FROM City WHERE

9istrict I >S"nla< Ban"#?3


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&'ercise (or matching

3 :o) many countries have a government that is anyform o( monarchy>

match any government containing Monarchy

:o) many are some (orm o( monarchy+ but not aConstitutional Monarchy @like .hailand>


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=41lan&-a&e?

FROM c"-ntrylan&-a&e

UUU


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=41lan&-a&e?


WHERE isO==icialT

.RO/5 B c"-ntryc"de

=41


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=41

SELECT c"-ntryc"de< c"-nt>lan&-a&e?


WHERE isO==icialT

.RO/5 B c"-ntryc"de

HD7I. c"-nt>lan&-a&e? 6 1

= tti : l


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=etting :elp

1nline help (or :&L! (or the mysql command

:&L! (or SQL statements

mysql6 HEL5

mysql6 HEL5 SELECT

f "y#$l doesnt have help on #%& commands' then load the (help

tables( data onto your server) *ownload help table data from+

htt,2++de3.m!sql.com+do4nloads in the #Documentation# section

S b i


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Sub$ueries

SELECT ma>'"'-lati"n? FROM c"-ntry?3

To use sub$ueries in "y#%& you need version ,)- or newer)

Subquery

& i


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&'ercise

"n )hich country do people live the longest> :o) long to they live>

SELECT ame< Li=eE'ectancy

FROM c"-ntry

WHERE Li=eE'ectancy > insert s-$q-ery ere ?

3

L"M". i t d ( b


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L"M". instead o( sub$uery

Another )ay to get a #most# or #least# result/

14D&4 results by )hat you )ant


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&'ercise

2hich nation is the most cro)ded> *ind the country )ith ma'imum population density

@population per s$ km

Sho) the name and the population density

:int/ create an alias (or a computed (ield/

sql6 SELECT name< '"'-lati"ns-r=aceDrea DS density WHERE )))

Alias/ density /N population0sur(aceArea

& i


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&'ercise

"s .hailand richer than other countries in Southest Asia> List the name and =E!0population @N)ealth

o( countries in the same region as .hailand

use a sub$uery (or #the region of Thailand #/

SELECT )))

FROM C"-ntry

WHERE re&i"n >SELECT re&i"n WHERE )))? OR9ER B )))3

order the results by wealth

& i i i lth


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&'ercise/ increasing )ealth

*hailand has decided to anne' /invade0 eitherCambodia, #aus, 1ietnam, or Malaysia.

*he invaded country $ill become part of the ne$

*hailand.

*he government $ants the combined country to bewealthier than *hailand is no$. 2$ealth2 means(%)3population.

What country should Thailand invade?

D t D (i iti C d


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Data De(inition Commands

These commands alter the structure of a database

CREATE create a .able+ "nde'+ or Database

ATER modi(y structure o( a Database or .able

DRO delete an entire .able+ "nde'+ or Database

RE"A#E rename a .able

C ti . bl


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Creating a .able

.o add a ne) table to a database/

CREDTE TDBLE ta$lename

>=ield1< =ield,< ))) ?

"'ti"ns 3

sql6 CREDTE TDBLE C/STOMER >

acc"-nt-m$er 7DRCHDR>G? OT /LL<

clientI9 7DRCHDR>8:? OT /LL< $alance 9O/BLE 9EFD/LT :<

availa$leBalance 9O/BLE 9EFD/LT :

? 3

P-ery OK< : r"!s a==ected)

!rod cti it :int


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!roductivity :int

.ype the #C4&A.& .ABL statement into a (ile #source# the (ile in mys$l/ s"-rce =ilename3

CREDTE TDBLE C/STOMER >

acc"-nt-m$er CHDR>1:? OT /LL<clientI9 7DRCHDR>8:? OT /LL<

$alance 9O/BLE 9EFD/LT :<

availa$leBalance 9O/BLE 9EFD/LT :<

5RIMDR KE> clientI9 ?

? 3

*ile/ tem'createta$le)sql

sql6 SO/RCE tem'createta$le)sql3


Deleting 4ecords a .able


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Deleting 4ecords a .able

,ou must speci(y a #2:&4 clause (or ro)s to delete

"( there is no #2:&4+ it deletes all rows

9ELETE FROM ta$lename

WHERE condition 3

first use SELECT to verify condition

sql6 SELECT * FROM city

WHERE nameBan&saen3

sql6 9ELETE FROM city

WHERE nameBan&saen3

P-ery OK< 1 r"! a==ected)

&'ercise


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&'ercise

Delete the city you added to the City table

1n a (riends machine+ is it deleted immediately >

Deleting a .able


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Deleting a .able

4emove a table (rom the database

9RO5 TDBLE ta$lename 3

sql6 9RO5 TDBLE C/STOMER 3

8ie)s


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8ie)s

A 8ie) is like a #virtual table# containing selected data(rom one or more real tables

C"-ntry

ame

C"ntinentC"de

)))

C"-ntryLan

&-a&eLan&-a&e

5ercenta&e

isO==icial

)))

MyView

ame

Lan&-a&e

5ercenta&e

CREDTE 7IEW My7ie! DS )))

8ie) &'ample


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8ie) &'ample

Create a vie) (or country name+ languages+ andpercentage

sql6 CREDTE 7IEW lang

DS

SELECT name< lan&-a&e< 'ercenta&e


WHERE C)c"de L)c"-ntryc"de

OR9ER B lan&-a&e DSC3P-ery OK< : r"!s a==ected)

sql6 SELECT * FROM lang WHERE lan&-a&eTai3


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!roductivity :int

.ype the #C4&A.& 8"&2# statement into a (ile 4ead the (ile into mys$l/ s"-rce =ilename3

CREDTE 7IEW lang DS

SELECT name< lan&-a&e< 'ercenta&e


WHERE C)c"de L)c"-ntryc"de3

*ile/ lan&vie!)sql

sql6 SO/RCE lan&vie!)sql3


&'ercise


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&'ercise

Create a vie) that sho)s these (ields/City)name as name

C"-ntry)name as c"-ntry

Re&i"n

5"'-lati"n o( the cityO==icial lan&-a&e

id "= te city

&ach person should use a di((erent name (or his vie)+ toavoid inter(ering )ith each other

List the tables in )orld @ s"! ta$les

&'ercise


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&'ercise

List the cities in Southest Asia )here &nglish is theo((icial language and population is over 3+

&'ercise


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&'ercise

Ask MySQL to #describe# your vie)

Delete your vie)/

9RO5 7IEW viewname 3

4evie)


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4evie)

2hat is the command to

3 list all the databases that you have access to>

5 use the Bank database>

6 vie) a list o( tables in Bank>

7 vie) the structure o( the Accounts table>


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SQL Qui?

Database =ame

8ocabulary


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8ocabulary

#largest # and #smallest # re(er to si?e @sur(aceArea

#most populous#+ #least populous# re(er to populationand population H @e'clude unpopulated nations

#richest #+ # poorest # means GNP per capita not total =E!+and =E! H @=E! N means no data

#most crowded # re(ers to population0sur(aceArea

Language :ints


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Language :ints

#.ortran is an official language# means its an o((iciallanguage o( the country

#Pascal is spoken unofficially # means it is spoken+ but

not an o((icial language

#/O0O& is spoken# means C1B1L is a languageand percentage H

2hat is the 2orlds Smallest Eation>


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2hat is the 2orld s Smallest Eation>

:o) big is it>

2hat is the Largest Country in A(rica>


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2hat is the Largest Country in A(rica>

Sho) the SQL :o) big is it>

2hat are the !oorest Countries inAsia>


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Asia>

must have =E! data @=E! H

List 6 poorest nations

2hat is the =E! per person>

E1.&/ =E! is measured in O3++ Multiply yourans)er by 3++ to get


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Middle &ast @region>

2hat is the =E! per person> Sho) result is


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"n )hat countries is .hai spoken>

SE#EC$ ...

FROM Count! C

5OI' Count!#anguage #

O' C.code 6 #.count!code

WHERE ...

:o) many people speak &nglish>


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:o) many people speak &nglish>

5 $ueries/ ho) many in each country

total (or )orld

SE#EC$ ...

FROM Count! C


O' C.code 6 #.count!code

WHERE ...

:istory o( &mpires through Language


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Empires are cultures that spread over many countries

2e can detect past &mpires by the spread of language

2hat languages are spoken in greatest number o( countries>

Can you name the &mpire>



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2e can detect past &mpires by the spread of language

2hat languages are spoken in greatest number o(countries>

SELECT #.language*sum%#.,ecentage7C.,o,ulation) 8S sum

FROM Count! C

OI Count!#anguage #

O C.code 6 #.count!code

.RO/5 B #.language

OR9ER B sum DESC

2hat cities have a population H PM >


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2hat cities have a population PM >

!rint city name+ population+ and country name Sort by population -- largest (irst

9:::::::::::::::::9::::::::::::9:::::::::::::::::::::::::9

; name ; ,o,ulation ; count!


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2here is Dari the 1((icial Language>

"n )hat country is Dari the o((icial language>

7 o((icial languages>


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7 o((icial languages>

2hat country in &urope has 7 o((icial languages>

SE#EC$ ...

FROM Count! C


O' C.code 6 #.count!code WHERE ...

&RO1( B" C.code :: gou, b! count!

H8I'& ...

4esources


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4esources

MySQL http/00devmys$lcom0tech-resources0articles0

Learning SQL

http/00))))6schoolscom0s$l0nice tutorial and command re(erence

Documents

1-SQL-Basics.ppt