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Objectives
Aftercompletingthislesson,youshouldbeabletodo
thefollowing:
•Limittherowsthatareretrievedbyaquery
•Sorttherowsthatareretrievedbyaquery
•UseampersandsubstitutioniniSQL*Plusto
restrictandsortoutputatruntime
LimitingRowsUsingaSelection
EMPLOYEES
…
“retrieveall
employeesin
department90”
LimitingtheRowsThatAreSelected
•Restricttherowsthatarereturnedbyusingthe
WHEREclause:
SELECT*|{[DISTT]column|expression[alias],...}
FROMtable
[WHEREcondition(s)];
•TheWHEREclausefollowstheFROMclause.
UsingtheWHEREClause
SELECTemployee_id,last_name,job_id,department_id
FROMemployees
WHEREdepartment_id=90;
CharacterStringsandDates
•Characterstringsanddatevaluesareenclosedby
singlequotationmarks.
•Charactervaluesarecase-sensitive,anddate
valuesareformasitive.
•ThedefauateformatisDD-MON-RR.
SELECTlast_name,job_id,department_id
FROMemployees
WHERElast_name=King;
ComparisonConditions
OperatorMeaning
=Equalto
Greaterthan
=Greaterthanorequalto
Lessthan
=Lessthanorequalto
Notequalto
BETWEENBetweentwovalues
...AND...(lusive)
IN(set)Matchanyofalistofvalues
LIKEMatchacharacterpattern
ISNULLIsanullvalue
UsingComparisonConditions
SELECTlast_name,salary
FROMemployees
WHEREsalary=3000;
UsingthWEENCondition
UsethWEENconditi
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