Rollup function in group by clause

Rollup function in group by clause

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Create Table:
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create table Employee(
ID VARCHAR2(4 BYTE) NOT NULL,
First_Name VARCHAR2(10 BYTE),
Last_Name VARCHAR2(10 BYTE),
Start_Date DATE,
End_Date DATE,
Salary Number(8,2),
City VARCHAR2(10 BYTE),
Description VARCHAR2(15 BYTE)
);
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Insert values into table::
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insert into Employee (ID, First_Name, Last_Name, Start_Date,End_Date,Salary,City,Description)
values ('01','Jason','Martin', to_date('19960725','YYYYMMDD'), to_date('20060725','YYYYMMDD'), 1234.56, 'Toronto', 'Programmer');



insert into Employee (ID, First_Name, Last_Name, Start_Date,End_Date,Salary,City,Description)
values ('02','Alison', 'Mathews', to_date('19760321','YYYYMMDD'), to_date('19860221','YYYYMMDD'), 6661.78, 'Vancouver','Tester');



insert into Employee (ID, First_Name, Last_Name, Start_Date,End_Date,Salary,City,Description)
values ('03','James','Smith', to_date('19781212','YYYYMMDD'), to_date('19900315','YYYYMMDD'), 6544.78, 'Vancouver','Tester');



insert into Employee (ID, First_Name, Last_Name, Start_Date,End_Date,Salary,City,Description)
values ('04','Celia','Rice',to_date('19821024','YYYYMMDD'), to_date('19990421','YYYYMMDD'), 2344.78, 'Vancouver','Manager');


insert into Employee (ID, First_Name, Last_Name, Start_Date,End_Date,Salary,City,Description)
values ('05','Robert', 'Black', to_date('19840115','YYYYMMDD'), to_date('19980808','YYYYMMDD'), 2334.78, 'Vancouver','Tester');


insert into Employee (ID, First_Name, Last_Name, Start_Date,End_Date,Salary,City,Description)
values ('06','Linda','Green', to_date('19870730','YYYYMMDD'), to_date('19960104','YYYYMMDD'), 4322.78,'New York', 'Tester');


insert into Employee (ID, First_Name, Last_Name, Start_Date,End_Date,Salary,City,Description)
values ('07','David','Larry', to_date('19901231','YYYYMMDD'), to_date('19980212','YYYYMMDD'), 7897.78,'New York', 'Manager');


insert into Employee (ID, First_Name, Last_Name, Start_Date,End_Date,Salary,City,Description)
values ('08','James','Cat', to_date('19960917','YYYYMMDD'), to_date('20020415','YYYYMMDD'), 1232.78,'Vancouver', 'Tester');
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Operation :
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1) Seclect * from employee;
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Output:


ID FIRST_NAME LAST_NAME START_DATE END_DATE SALARY CITY DESCRIPTION
---- ---------- ---------- ----------- ----------- ---------- ---------- ---------------
01 Jason Martin 1996-JUL-25 2006-JUL-25 1234.56 Toronto Programmer
02 Alison Mathews 1976-MAR-21 1986-FEB-21 6661.78 Vancouver Tester
03 James Smith 1978-DEC-12 1990-MAR-15 6544.78 Vancouver Tester
04 Celia Rice 1982-OCT-24 1999-APR-21 2344.78 Vancouver Manager
05 Robert Black 1984-JAN-15 1998-AUG-08 2334.78 Vancouver Tester
06 Linda Green 1987-JUL-30 1996-JAN-04 4322.78 New York Tester
07 David Larry 1990-DEC-31 1998-FEB-12 7897.78 New York Manager
08 James Cat 1996-SEP-17 2002-APR-15 1232.78 Vancouver Tester

8 rows selected.

ROLLUP operation:
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SELECT city, SUM(salary)
FROM employee
GROUP BY ROLLUP(city) ;
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Output :

CITY SUM(SALARY)
---------- -----------
New York 12220.56
Toronto 1234.56
Vancouver 19118.9
32574.02


To view one record from table:
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SELECT ID, First_Name, Last_Name, Start_Date,End_Date,Salary,City,Description
FROM employee
WHERE ID=2;
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