The document describes a series of SQL commands used to create, alter, insert data into, and query tables named EMP_TAB and DEPT_TAB. The commands create the tables with various columns and constraints, insert sample data, and add, modify and delete columns. Queries are written to find matching records and aggregate data from the tables.

1. 1) Create a table called Employ with the following structure.
Name Type
empno Number(6)
ename VARCHAR2(20)
Job VARCHAR2(20)
MGR NUMBER(4)
SAL NUMBER(7,2)
SQL> create table emp_tab(empno number(6), ename varchar2(20),
job varchar2(20), mgr number(4), sal number(7,2));
2)Add a column commission to the Employ table ‘deptno‘, numeric null allowed.
SQL> alter table emp_tab add (comm number,deptno number);
Table altered.
SQL> desc emp_tab;
Name Null? Type
----------------------------------------- -------- ------------
EMPNO NUMBER(6)
ENAME VARCHAR2(20)
JOB VARCHAR2(20)
MGR NUMBER(4)
SAL NUMBER(7,2)
COMM NUMBER
DEPTNO NUMBER
3)Modify the column width of the job field of Employ table.
SQL> alter table emp_tab modify (job varchar2(22));
Table altered.
SQL> desc emp_tab;
Name Null? Type
----------------------------------------- -------- ------------
EMPNO NUMBER(6)
ENAME VARCHAR2(20)
JOB VARCHAR2(22)
MGR NUMBER(4)
SAL NUMBER(7,2)
COMM NUMBER
DEPTNO NUMBER
4) Create dept table with the fields deptno,dname,loc.
SQL> create table dept_tab(deptno number(3),dname varchar2(15),loc
varchar2(15));
5) Add constraints to the Employ table that empno as the primary key
SQL> alter table emp_tab add primary key(empno);
Table altered.
SQL> desc emp_tab;
Name Null? Type
----------------------------------------- -------- -------------

2. EMPNO NOT NULL NUMBER(6)
ENAME VARCHAR2(20)
JOB VARCHAR2(22)
MGR NUMBER(4)
SAL NUMBER(7,2)
COMM NUMBER
DEPTNO NUMBER
7) Add constraints to the Department table that deptno as the primary key
SQL> alter table dept_tab add primary key(deptno);
Table altered.
SQL> desc dept_tab;
Name Null? Type
----------------------------------------- -------- -------------
DEPTNO NOT NULL NUMBER(3)
DNAME VARCHAR2(15)
LOC VARCHAR2(15)
8) Add deptno as the foreign key in Employ table.
SQL> alter table emp_tab add constraint foreign key references dept_tab(deptno);
9) Add constraints to the Employ table to check the empno value while entering
(i.e) empno > 100.
SQL> alter table emp_tab add check (empno>100);
10) Add columns Dob to the Employ table
SQL> alter table emp_tab add (dob date);
11) Add and drop a column bloodgroup to the Employ table
SQL> alter table emp_tab drop (key,blood_grp);
Table altered.
SQL> desc emp_tab;
Name Null? Type
----------------------------------------- -------- ------------
EMPNO NOT NULL NUMBER(6)
ENAME VARCHAR2(20)
JOB VARCHAR2(22)
MGR NUMBER(4)
SAL NUMBER(7,2)
COMM NUMBER
DEPTNO NUMBER
DOB DATE
12) Insert the any three records in the Department table as shown below and use
rollback? Check the result?
SQL> insert into dept_tab values(&deptno,'&dname','&loc');
Enter value for deptno: 111
Enter value for dname: Finance
Enter value for loc: unit 1
old 1: insert into dept_tab values(&deptno,'&dname','&loc')
new 1: insert into dept_tab values(111,'Finance','unit 1')

3. 1 row created.
SQL> /
Enter value for deptno: 222
Enter value for dname: Admin
Enter value for loc: unit 1
old 1: insert into dept_tab values(&deptno,'&dname','&loc')
new 1: insert into dept_tab values(222,'Admin','unit 1')
1 row created.
SQL> /
Enter value for deptno: 333
Enter value for dname: Production
Enter value for loc: unit 2
old 1: insert into dept_tab values(&deptno,'&dname','&loc')
new 1: insert into dept_tab values(333,'Production','unit 2
1 row created.
SQL> /
Enter value for deptno: 444
Enter value for dname: Welding
Enter value for loc: unit 2
old 1: insert into dept_tab values(&deptno,'&dname','&loc')
new 1: insert into dept_tab values(444,'Welding','unit 2')
1 row created.
SQL> /
Enter value for deptno: 555
Enter value for dname: Shipping
Enter value for loc: unit 3
old 1: insert into dept_tab values(&deptno,'&dname','&loc')
new 1: insert into dept_tab values(555,'Shipping','unit 3')
1 row created.
SQL> select * from dept_tab;
DEPTNO DNAME LOC
---------- --------------- ---------------
111 Finance unit 1
222 Admin unit 1
333 Production unit 2
444 Welding unit 2
555 Shipping unit 3
SQL> roll back;
Rollback complete.
SQL> select * from dept_tab;
no rows selected
13) Insert the any three records in the dept table shown below and use commit?
Check the result?
SQL> insert into dept_tab values(&deptno,'&dname','&loc');
Enter value for deptno: 111
Enter value for dname: Finance
Enter value for loc: Unit 1
old 1: insert into dept_tab values(&deptno,'&dname','&loc')
new 1: insert into dept_tab values(111,'Finance','Unit 1')

4. 1 row created.
SQL> /
Enter value for deptno: 222
Enter value for dname: Admin
Enter value for loc: Unit 1
old 1: insert into dept_tab values(&deptno,'&dname','&loc')
new 1: insert into dept_tab values(222,'Admin','Unit 1')
1 row created.
SQL> /
Enter value for deptno: 333
Enter value for dname: Production
Enter value for loc: Unit 2
old 1: insert into dept_tab values(&deptno,'&dname','&loc')
new 1: insert into dept_tab values(333,'Production','Unit 2')
1 row created.
SQL> /
Enter value for deptno: 444
Enter value for dname: Welding
Enter value for loc: Unit 2
old 1: insert into dept_tab values(&deptno,'&dname','&loc')
new 1: insert into dept_tab values(444,'Welding','Unit 2')
1 row created.
SQL> /
Enter value for deptno: 555
Enter value for dname: Packing
Enter value for loc: Unit 3
old 1: insert into dept_tab values(&deptno,'&dname','&loc')
new 1: insert into dept_tab values(555,'Packing','Unit 3')
1 row created.
SQL> /
Enter value for deptno: 666
Enter value for dname: Shipping
Enter value for loc: Unit 3
old 1: insert into dept_tab values(&deptno,'&dname','&loc')
new 1: insert into dept_tab values(666,'Shipping','Unit 3')
1 row created.
SQL> commit;
Commit complete.
SQL> select * from dept_tab;
DEPTNO DNAME LOC
---------- --------------- ---------------
111 Finance Unit 1
222 Admin Unit 1
333 Production Unit 2
444 Welding Unit 2
555 Packing Unit 3
666 Shipping Unit 3
6 rows selected.

5. SQL> roll back;
Rollback complete.
SQL> select * from dept_tab;
DEPTNO DNAME LOC
---------- --------------- ---------------
111 Finance Unit 1
222 Admin Unit 1
333 Production Unit 2
444 Welding Unit 2
555 Packing Unit 3
666 Shipping Unit 3
6 rows selected.
14) Delete one row with deptno=333 from dept table and display the table. Now
use undo the changes by using appropriate command.
SQL> delete from dept_tab where deptno=333;
1 row deleted.
SQL> select * from dept_tab;
DEPTNO DNAME LOC
---------- --------------- ---------------
111 Finance Unit 1
222 Admin Unit 1
444 Welding Unit 2
555 Packing Unit 3
666 Shipping Unit 3
SQL> roll back;
Rollback complete.
SQL> select * from dept_tab;
DEPTNO DNAME LOC
---------- --------------- ---------------
111 Finance Unit 1
222 Admin Unit 1
333 Production Unit 2
444 Welding Unit 2
555 Packing Unit 3
666 Shipping Unit 3
6 rows selected.
15) Insert rows into Employ table
SQL> insert into emp_tab values(&empno,'&ename','&job',&mgr,&sal,&comm,&deptno,'
&dob');
SQL> /
Enter value for empno: 121
Enter value for ename: Chang
Enter value for job: Analyst
Enter value for mgr: 5
Enter value for sal: 45000
Enter value for comm: 500
Enter value for deptno: 333
Enter value for dob: 12-Jan-1990
old 1: insert into emp_tab values(&empno,'&ename','&job',&mgr,&sal,&comm,&dept
no,'&dob')

6. new 1: insert into emp_tab values(121,'Chang','Analyst',5,45000,500,333,'12-Ja
n-1990')
1 row created.
SQL> /
Enter value for empno: 122
Enter value for ename: Marroou
Enter value for job: Auditor
Enter value for mgr: 131
Enter value for sal: 67000
Enter value for comm: 111
Enter value for deptno: 111
Enter value for dob: 23-Mar-1981
old 1: insert into emp_tab values(&empno,'&ename','&job',&mgr,&sal,&comm,&dept
no,'&dob')
new 1: insert into emp_tab values(122,'Marroou','Auditor',131,67000,111,111,'2
3-Mar-1981')
1 row created.
SQL> /
Enter value for empno: 131
Enter value for ename: Sheeshoo
Enter value for job: Manager
Enter value for mgr: 999
Enter value for sal: 90000
Enter value for comm: 700
Enter value for deptno: 111
Enter value for dob: 13-May-1972
old 1: insert into emp_tab values(&empno,'&ename','&job',&mgr,&sal,&comm,&dept
no,'&dob')
new 1: insert into emp_tab values(131,'Sheeshoo','Manager',999,90000,700,111,'
13-May-1972')
1 row created.
SQL> /
Enter value for empno: 132
Enter value for ename: Kiyow
Enter value for job: Manager
Enter value for mgr: 999
Enter value for sal: 90000
Enter value for comm: 700
Enter value for deptno: 333
Enter value for dob: 25-Jul-1978
old 1: insert into emp_tab values(&empno,'&ename','&job',&mgr,&sal,&comm,&dept
no,'&dob')
new 1: insert into emp_tab values(132,'Kiyow','Manager',999,90000,700,333,'25-
Jul-1978')
1 row created.
SQL> /
Enter value for empno: 999
Enter value for ename: Jangchee
Enter value for job: BusinesHead
Enter value for mgr: 0
Enter value for sal: 99999
Enter value for comm: 0
Enter value for deptno: 222
Enter value for dob: 30-Sep-1969
old 1: insert into emp_tab values(&empno,'&ename','&job',&mgr,&sal,&comm,&dept
no,'&dob')

7. new 1: insert into emp_tab values(999,'Jangchee','BusinesHead',0,99999,0,222,'
30-Sep-1969')
1 row created.
SQL> select * from emp_tab;
EMPNO ENAME JOB MGR SAL
---------- -------------------- ---------------------- ---------- ----------
COMM DEPTNO DOB
---------- ---------- ---------
121 Chang Analyst 132 45000
500 333 12-JAN-90
122 Marroou Auditor 131 67000
111 111 23-MAR-81
131 Sheeshoo Manager 999 90000
700 111 13-MAY-72
EMPNO ENAME JOB MGR SAL
---------- -------------------- ---------------------- ---------- ----------
COMM DEPTNO DOB
---------- ---------- ---------
132 Kiyow Manager 999 90000
700 333 25-JUL-78
999 Jangchee BusinesHead 0 99999
0 222 30-SEP-69
16) Issue a query to find all the employees who work in the same job as Sheeshoo
SQL> select * from emp_tab where job=(select job from emp_tab where ename='Shees
hoo');
EMPNO ENAME JOB MGR SAL
---------- -------------------- ---------------------- ---------- ----------
COMM DEPTNO DOB
---------- ---------- ---------
131 Sheeshoo Manager 999 90000
700 111 13-MAY-72
132 Kiyow Manager 999 90000
700 333 25-JUL-78
17) Issue a query to display information about employees who earn more than any
employee in dept 333.
SQL> select * from emp_tab where sal=(select max(sal) from emp_tab where deptno=
333) and deptno=333;
EMPNO ENAME JOB MGR SAL
---------- -------------------- ---------------------- ---------- ----------
COMM DEPTNO DOB
---------- ---------- ---------
132 Kiyow Manager 999 90000
700 333 25-JUL-78