1 Chapter Ten Multiple Row Functions/Join: Objectives: -Multiple row functions -Ordering -Grouping -Concept of JOIN

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Chapter TenMultiple Row Functions/Join:Objectives:

-Multiple row functions

-Ordering-Grouping-Concept of JOIN

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Aggregate Functions:

• MAX (DISTINCT | ALL) (value)

• MIN (DISTINCT | ALL) (value)

• AVG (DISTINCT | ALL) (value)

• SUM (DISTINCT | ALL) (value)

• COUNT (DISTINCT | ALL) (value)*

• STDDEV (DISTINCT | ALL) (value)

• VARIANCE (DISTINCT | ALL) (value)

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• COUNT (*)

• COUNT (id)

• COUNT (DISTINCT ID)

• MAX (Birth_date)

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SUM (exp)

• SUM (exp) [ OVER (analytic_clause) ]

SELECT ID, name, salary,SUM (Salary)

OVER (ORDER BY salary) “Cumulating sum”

FROM Faculty;• NAME SALARY DEPT Cumulating sum

• -------------------------------------------------------------

• Hook 25000 MATH 25000

• Johnson 30000 MATH 55000

• Williams 34000 COSC 89000

• Jackson 45000 COSC 134000

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SUM (exp)

SELECT ID, name, salary, SUM (Salary) OVER (PARTITION BY Dept ORDER BY salary) “Cumulating sum”

FROM Faculty;• NAME SALARY DEPT Cumulating sum

• ------------------------------------------------------------------

• William 34000 COSC 34000

• Jackson 45000 COSC 79000

• Hook 25000 MATH 25000

• Johnson 30000 MATH 55000

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• List the highest GPA

SELECT MAX (GPA)

FROM Student;

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• List average, max, min, and total salary of cosc faculty

SELECT AVG(salary), MIN(salary),

MAX(salary), SUM(salary)

FROM faculty

WHERE dept = ‘COSC’;

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• List average salary of cosc faculty:

SELECT AVG(NVL(salary,0)),

AVG (salary), COUNT(*)

FROM faculty

WHERE dept = ‘COSC’;

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• LEAD: Access to more than one row• List faculty with the hired date and the

next hired date after each one• SELECT name, hired_date,

LEAD(hired_date,1) OVER(ORDER BY

hired_date) AS “next hired”

FROM faculty;

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• RANK (exp, exp, …) WITHIN GROUP• RANK ( ) OVER ( [partition] ORDER BY)

SELECT RANK(24000) WITHIN GROUP(ORDER BY Salary DESC) “Rank of $24,000

Salary”FROM Faculty;

SELECT RANK(24000, ‘PROFESSOR’) WITHIN GROUP(ORDER BY Salary, P_Rank) “Rank”

FROM Faculty;

SELECT Name, Salary, RANK() OVER (PARTITION BY Dept_Name

ORDER BY Salary, P_Rank) “Rank”FROM FacultyWHERE Dept = ‘COSC’;

Rank:

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Distinct:

SELECT DISTINCT (dept)FROM Faculty;

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User:

SELECT USER, UIDFROM DUAL;

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USERENV:• USERENV (‘Parameter’)

parameters:ENTRYID -- current audit entry numberISDBA -- True if s/he in DBA privilegeLANG -- Language used SESSIONID --Session IDTERMINAL --Operating System ID --for the Terminal of current

session

SELECT USERENV(‘LANG’) ‘Language’FROM DUAL;

LANGUAGE----------------------------AMERICAN_AMERICA.WE8ISO8859P1

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Ordering

• ORDERING: (Default is Ascending ASC)

• List students name in an alphabetic order

SELECT nameFROM studentORDER BY name;

ORDER BY Name , GPA DESC, Major;

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Ordering

• List of the faculty salary for the next year with 5% increase order by new salary.

SELECT name,

salary pay, salary+salary*0.05 AS new_salary

FROM facultyORDER BY new_salary;

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Grouping

SELECT

FROM

[WHERE]

[GROUP BY]

[ORDER BY]

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Grouping

• Average Salary of faculty members by department

SELECT dept, AVG(Salary)

FROM Faculty

GROUP BY dept;

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Grouping

• List number of courses taken by each student

SELECT ID, COUNT(*)

FROM Student_Course

GROUP BY ID;

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Grouping by multiple attributes

• List total number of credits taken by each student

SELECT ID, SUM(Cr)

FROM Student_CourseGROUP BY ID;

SELECT ID, semester, SUM(Cr)FROM Student_CourseGROUP BY ID, semester;

SELECT dept, count(name)FROM facultyGROUP BY dept;

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Having

• Condition on Group:

SELECT

FROM

[WHERE]

[GROUP BY]

[HAVING]

[ORDER BY]

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Having

List ID of students who have more than 20 credits and majoring in COSC.

SELECT ID, SUM (Cr)

FROM Student_Course

WHERE Major = 'COSC'

GROUP BY ID

HAVING SUM(Cr) > 20 ;

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Having

• SELECT dept, MAX(salary)

FROM faculty

GROUP BY Department

HAVING MAX(salary)>50000;

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Having

• SELECT dept, MAX(salary) a

FROM faculty

GROUP BY Dept

HAVING a >50000

ORDER BY MAX(salary);

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Having

• SELECT dept, MAX(SUM(salary))

FROM faculty

GROUP BY dept;

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Illegal Queries:

• SELECT name, count(*) FROM Department;

SELECT name, count(*) FROM Department GROUP BY name;

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Illegal Queries:

SELECT name, AVG(salary) FROM Department WHERE AVG(salary) >5000;

SELECT name, AVG(salary) FROM Department GROUP BY name HAVING AVG(salary) >5000;

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JOIN:

• Definition

• General Format:

• SELECT col1,col2,….

FROM table1, table2,…

WHERE conditions;

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JOIN:

• List of students’ name with the grade = 'A' • SELECT Name

FROM Student_Course, StudentWHERE Student.ID =

Student_Course.ID AND Grade

=‘A’;

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JOIN:

• Aliases:

SELECT Name

FROM Student_Course sc,

Student s

WHERE s.ID = sc.ID AND Grade =‘A’;

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CARTESIAN PRODUCT:

– Join condition is omitted– Join condition is invalid– All rows in table one are joined to all rows in

table two

SELECT *

FROM Student, faculty;

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JOIN

• Equijoin/Natural:

SELECT NameFROM Student_Course, StudentWHERE Student.ID = Student_Course.ID ;

SELECT NameFROM Student_Course

NATURAL JOIN Student ;

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JOIN

• Equijoin/Natural:

SELECT Name

FROM Student_Course

INNER JOIN Student ;

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JOIN

• Inner Join:

SELECT a.Name

FROM Student_Course b

INNER JOIN Student a

ON a.ID = b.ID ;

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JOIN

• Equijoin:

SELECT department.num_faculty,faculty.nameFROM department, facultyWHERE department.name=faculty.dept;

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JOIN

• Non-Equijoin:

Faculty (name, salary)Status (rank, low_salry, high_salary)

• Get the name, salary and rank of faculty members

• SELECT name, salary, rankFROM faculty, statusWHERE salary BETWEEN low_salary AND high_salary;

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JOIN

• Outer Join:

List of books that have been checked out:

SELECT DISTINCT title

FROM CheckedBook ;

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JOIN

• Outer Join:

List of books that have not been checked out:


FROM ShelfBook ;

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JOIN

• Outer Join:

List of all books:??SELECT DISTINCT title FROM ShelfBook a,

CheckedBook bWHERE a.ID=b.ID ;

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JOIN

• Outer Join:

List of all books:

SELECT title, MAX(b.R_date-b.C_date)

FROM ShelfBook a,

CheckedBook b

WHERE a.ID (+) = b.ID ;

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JOIN

• ANSI SQL Outer Join:

List of all books:


FROM

ShelfBook b RIGHT OUTER JOIN CheckedBook a ON

a.ID = b.ID ;

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JOIN


List of all books:


FROM

CheckedBook a LEFT OUTER JOIN ShelfBook b ON

a.ID = b.ID ;

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JOIN


List of all books:


FROM

CheckedBook a FULL OUTER JOIN ShelfBook b ON

a.ID = b.ID ;

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JOIN

• Outer Join:

• SELECT department.num_faculty, faculty.name

FROM department, faculty

WHEREdepartment.name(+)=faculty.dept

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JOIN

• Outer Join:

• SELECT department.num_faculty, faculty.name

FROM

department LEFT OUTER JOIN faculty ON department.name=faculty.dept;

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JOIN

• Self Join

SELECT a.Name

FROM Student a, Student b

WHERE a.ID > b.ID AND

b.Name = 'SMITH';

What is the output of this query

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JOIN

• Self Join• List of Faculty member with salary higher than

salary of Mary and less than salary of John SELECT a.Name

FROM Faculty a, Faculty b, Faculty cWHERE a.Salary > b.Salary AND

a.Salary < c.Salary ANDb.Name = 'MARY' ANDc.Name = 'JOHN’;

Documents

1 Chapter Ten Multiple Row Functions/Join: Objectives: -Multiple row functions -Ordering -Grouping -Concept of JOIN