Cornea Madalina - Tema2

8/12/2019 Cornea Madalina - Tema2

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Section 2 Lesson 1: Using Variables in PL/SQL

Vocabulary

Identify the vocabulary word for each definition below:Use variables-Used for storage of data and manipulation of stored values.

Parameters- values passed to a program by a user or by another program to customize the

program.

Try It / Solve It

1. Fill in the blanks.

A. ariables can be assigned to the output of aPL/SQL subprogram

!. ariables can be assigned values in the declarative section of a "#$% block

'. ariables can be passed asparameters to PL/SQLto subprograms.

(. Identify valid and invalid variable declaration and initialization

number)of)copies "#%)I*+,-,/

printer)name '0*%+A*+ A'A(2134/

deliver)to A'A(2134:56ohnson/

by)when 7A+,:5 %8%7A+,91/

. ,;amine the following anonymous block and choose the appropriate statement.

7,'#A,

fname A'A(2(34/

lname A'A(21%)0U+"U+."U+)#I*,2 F*A>, ??= = ??lname4/

,*7/

A. +he block will e;ecute successfully and print @fernandez.

!. +he block will give an error because the fname variable is used without initializing.

'. +he block will e;ecute successfully and print @null fernandez .

7. +he block will give an error because you cannot use the 7,FAU#+ keyword to initialize a variable

of the A'A( type.

,. +he block will give an error because the F*A>, variable is not declared.


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B. In Application ,;press:

A. 'reate the following function:

',A+, FU*'+I0* num)characters 2p)string I* A'A(4,+U* I*+,-, A%

v)num)characters I*+,-,/

!,-I*

%,#,'+ #,*-+2p)string4 I*+0 v)num)characters

F0> dual/

,+U* v)num)characters/

,*7/

!. 'reate and e;ecute the following anonymous block:

7,'#A,

v)length)of)string I*+,-,/

!,-I*

v)length)of)string :5 num)characters2=0racle 'orporation=4/

7!>%)0U+"U+."U+)#I*,2v)length)of)string4/

,*7/


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Section 2 Lesson 2: Recogniing PL/SQL Le!ical Units

VocabularyIdentify the vocabulary word for each definition below:

LiteralE An e;plicit numericD character stringD dateD or !oolean value that is not represented by

an identifier

"elimitersE %ymbols that have special meaning to an 0racle database.

Reserve# $or#sE Cords that have special meaning to an 0racle database and cannot be used

as identifiers.

%ommentsE 7escribe the purpose and use of each code segment and are ignored by "#$%.

Le!ical unitsE !uilding blocks of any "#$% block and are seuences of characters including

lettersD digitsD tabsD returnsD and symbols.

I#enti&iers E A nameD up to 3 characters in lengthD given to a "#$% obGect.

Try It / Solve It Questions

1. Fill in the blanks.

A. An identifieris the name given to a "#$% obGect.

!. A reserved word is a word that has special meaning to the 0racle database.

'. A delimiters is a symbol that has special meaning to the 0racle database.

7. A literal is an e;plicit numericD character stringD dateD or !oolean value that is not

represented by an identifier.

,. A comments e;plains what a piece of code is trying to achieve.

(. Identify each of the following identifiers as valid or invalid. If invalidD specify why.

Identifier alid 2H4 Invalid2H4 Chy Invalid

+oday ;

#ast name ; 'ontine un spatiu

+odays)date H

number)of)days)in)february)this) year ; >ai mult de 3 de caractere

IsleapJyear H

Knumber H

*U>!,K H

*umber1toL H


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. Identify the reserved words in the following list.

Cord eserved

8$*

create 7a

make *u

table 7a

seat *u

alter 7a

rename 7a

row 7a

number 7a

web *u

B. Chat kind of le;ical unit 2for e;ample eserved wordD 7elimiterD #iteralD 'omment4 is each of the

following

alue #e;ical Unit

%,#,'+ eserved word

:5 'ompound 7elimiter

=+,%+= 'ommentFA#%, !oolean #iteral

EE new process 'omment

F0> eserved word

$Mselect the country with the highest elevation M$ 'omment

)test

B.3N *umeric comment


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Section 2 Lesson ': Recogniing "ata Ty(es

Vocabulary

Identify the vocabulary word for each definition below:

Large ob)ectE old valuesD called locatorsD that specify the location of large obGects 2such as

graphic images4 that are stored out of line.

Scalar E old a single value with no internal components.

%om(ositeE 'ontain internal elements that are either scalar 2record4 or composite 2record and

table4

Re&erenceE old valuesD called pointersD that point to a storage location.

*b)ect E A schema obGect with a nameD attributesD and methods.

Try It / Solve It

1. In your own wordsD describe what a data type is and e;plain why it is important.

Rezolvare :specificO ce tip i ce dimensiune de date poate fi utilizatD precum i modul Pn care

acesta este stocat


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Section 2 Lesson 4: Using Scalar Data Types

Vocabulary

Identify the vocabulary word for each definition below:

+ooleanEA datatype that stores one of the three possible values used for logicalcalculations: TRUE, FALE, or !ULL"

,TP. -Attribute used to declare a variable according to another previouslydeclared variable or database colu#n"

Try It / Solve It

1. $eclarations:A" %hich of the following variable declarations are valid&

Declaration Valid or

Invalid

anu#ber'of'students (L'I!TE)ER* Valid

b TU$E!T'!A+E AR-.AR/012345ohnson*Invalid

c stu'per'class -6!TA!T !U+7ER*Invalid

d to#orrow $ATE :4 8$ATE91* Valid

!. For those declarations in 1"A" that are invalid, describe why they are invalid"

Rezolvare :c" constanta nu are nicio valoare atribuita

'. %rite an anony#ous bloc in which you declare and print each of the variables in 1"A,correcting the invalid declarations"

Rezolvare:

7,'#A,number)of)students "#%)I*+,-,/%+U7,*+)*A>, A'A(2134:56ohnson/

stu)per)class '0*%+A*+ *U>!,2D(4 :5Q.(%)0U+"U+."U+)#I*,2= number)of)students 5 =?? number)of)students4/7!>%)0U+"U+."U+)#I*,2= %+U7,*+)*A>, 5 =?? %+U7,*+)*A>,4/

7!>%)0U+"U+."U+)#I*,2= stu)per)class 5 =?? stu)per)class4/7!>%)0U+"U+."U+)#I*,2= tomorrow 5 =?? tomorrow4/

,*7/

(. Evaluate the variables in the following code" Answer the following ;uestions about eachvariable" Is it na#ed well& %hy or why not& If it is not na#ed well, what would be a betterna#e and why&

$E-LARE

country'na#e AR-.AR/ 0


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7E)I!

ELE-T country'na#e, #edian'age I!T6 country'na#e, #edian'ageFR6+ wf'countries

%.ERE country'na#e 4 >United tates of A#erica>*$7+'6UT(UT"(UT'LI!E0> The #edian age in >??country'na#e??> is

>??#edian'age??>">3*E!$*

Rezolvare:variabilele country'na#e si #edian'age sunt folosite ca identificatori, desidesfinesc si nu#ele a doua ca#puri din tabela wf'countries

. E@a#ine the declarations in ;uestion /" -hange the declarations so that they use theT8(E attribute"

Rezolvare:

$E-LARE

v)country)name wf)countries.country)nameR+8",/

v)median)age wf)countries.median)ageR+8",:

B. In your own words, describe why using the T8(E attribute is better than hardBcoding data types" -an you e@plain how you could run into proble#s in the future byhardBcoding the data types of the country'na#e and #edian'age variables in;uestion /&

Rezolvare:Este folosit pentru a oferi Cn #od auto#at o variabilD cu acelea i datetipu i di#ensiuneca defini iea coloanei de bae de date,o altD variabilD declaratD

.ello %orld>3*E!$*

A" Add a declarative section to this (LGL bloc" In the declarative section, declarethe following variables:

S A variable na#ed T6$A8 of datatype $ATE" Initialie T6$A8 with 8$ATE"

S A variable na#ed T6+6RR6% with the sa#e datatype as T6$A8" Use theT8(E attribute to declare this variable"

Rezolvare:

$E-LARET6$A8 $ATE:48$ATE*T6+6RR6% T6$A8T8(E*

! " In the e@ecutable section, initialie the T6+6RR6% variable with an e@pressionthat calculates to#orrowHs date 0add 1 to the value in T6$A83" (rint the value of T6$A8and T6+6RR6% after printing .ello %orldH"

Rezolvare:

7E)I!T6+6RR6% :4 T6$A8 91*$7+'6UT(UT"(UT'LI!E0>.ello %orld>??> >??T6$A8??> >??T6+6RR6%3*


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E!$*

Hello World 03/Mar/2014 04/Mar/2014

Statement processed.

Section 2 Lesson 5: Writing L/S!L "#ecutable State$ents


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Vocabulary

Identify the vocabulary word for each definition below:.!(licit %onversions- 'onverts values from one data type to another by using builtEin

functions.Im(licit conversionsE 'onverts data types dynamically if they are mi;ed in a

statement.

Try it/solve it

1" E@a#ine the following code and then answer the ;uestions"

$E-LARE

@ AR-.AR/0/23*7E)I!

@:4 >1/J> 9 >K *

$7+'6UT(UT"(UT'LI!E0@3*E!$*

3 A" %hat do you thin the output will be when you run the above code&Rezolvare:


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+onth dd, yyyyH" tore the date in a $ATE variable called #y'date" -reate anothervariable of the $ATE type called v'last'day" Assign the last day of this #onth tov'last'day" $isplay the value of v'last'day"

Rezolvare:

$E-LARE#y'date $ATE:48$ATE*v'last'day $ATE :4 LAT'$A80#y'date3*

7E)I!$7+'6UT(UT"(UT'LI!E0T6'-.AR0#y'date,>+onth dd,8888>33*$7+'6UT(UT"(UT'LI!E0'LAT'$A83*

E!$*

March 03, 2014

31/Mar/2014

Statement processed.

B. +odify the progra# created in ;uestion J to add K< days to todayHs date and thencalculate and display the nu#ber of #onths between the two dates"

Rezolvare:

$E-LARE#y'date $ATE:48$ATE*v'last'day $ATE :4 #y'date9K


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$E-LARE

v'nu#ber !U+7ER*v'boolean 766LEA!*

7E)I!v'nu#ber :4 /


12/14

Identify the vocabulary word for each definition below.QULI3I.R-A label given to a block.Variable Sco(eE'onsists of all the blocks in which the variable is either local 2the declaring

block4 or global 2nested blocks within the declaring block4 .Variable VisibilityE+he portion of the program where the variable can be accessed without

using a ualifier.

Try It / Solve It

1. ,valuate the "#$% block below and determine the value of each of the followingvariables according to the rules of scoping.

7,'#A,weight *U>!,24 :5 Q33/

message A'A(2( employeesC,, employee)id 5 133/


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7,'#A,

v)employee)id employees.employee)idR+8",/v)Gob employees.Gob)idR+8",/

!,-I*

%,#,'+ employee)idD Gob)id I*+0 v)employee)idD v)GobF0> employees

C,, employee)id 5 13/7!>%)0U+"U+."U+)#I*,2v)employee)id?? = is a =??v)Gob4/

,*7/

7!>%)0U+"U+."U+)#I*,2v)employee)id?? = is a =??v)Gob4/,*7/

A. Chy does the inner block display the Gob)id of employee 13D not employee 1333 Rezolvare: pentru ca se afiseaza in blocul unde se e;trage valare 13

!. Chy does the outer block display the Gob)id of employee 133D not employee 13Rezolvare:pentru ca valoarea variabilei este cea din blocul e;tern

'. >odify the code to display the details of employee 133 in the inner block. Use block labels.TTouter

Section 2 Lesson %: &ood rogra$$ing ractices

Try It / Solve It

1"Enter and run the following (LGL bloc" It will e@ecute correctly if you have entered it


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correctly, but it contains so#e e@a#ples of bad progra##ing practice"

$E-LARE

#yvar1 AR-.AR/0/23* #yvar/nu#ber0K3*7E)I!ELE-T country'na#e I!T6 #yvar1

FR6+ wf'countries %.ERE country'id 4 1/K=*#yvar/ :4>1/JK>*

+8AR/ :4 #yvar/ N /*$7+'6UT(UT"(UT'LI!E0#yvar13* End*B

< A" +odify the bloc to use good progra##ing practice, and reBrun the bloc"

Q 7" 8our #odified bloc should contain e@a#ples of the following good progra##ingpractices: e@plicit data type conversions, #eaningful and consistent variable na#es, use ofT8(E, upper and lowercase conventions, single and #ultiBline co##ents, and clearindentation"

$E-LARE

#yvar1 AR-.AR/0/23*#yvar/ !U+7ER0K3*

7E)I!ELE-T country'na#e I!T6 #yvar1

FR6+ wf'countries %.ERE country'id 4 1/K=*

#yvar/ :4 >1/JK>*+8AR/ :4 #yvar/ N /*$7+'6UT(UT"(UT'LI!E0#yvar13*

E!$*

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Cornea Madalina - Tema2