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**Find the 3rd MAX salary in the emp table.****select distinct sal from emp e1 where 3 = (select count(distinct sal) from emp e2 where e1.sal <= e2.sal);**

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**Find the 3rd MIN salary in the emp table.**

select distinct sal from emp e1 where 3 = (select count(distinct sal) from emp e2where e1.sal >= e2.sal);
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**Select FIRST n records from a table.**

select * from emp where rownum <= &n;
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**Select LAST n records from a table**

select * from emp minus select * from emp where rownum <= (select count(*) - &n from emp);
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alternate solution: select * from dept a where not exists (select * from emp b where a.deptno = b.deptno);

altertnate solution: select empno,ename,b.deptno,dname from emp a, dept b where a.deptno(+) = b.deptno and empno is null;

**List dept no., Dept name for all the departments in which there are no employees in the department.**

select * from dept where deptno not in (select deptno from emp);alternate solution: select * from dept a where not exists (select * from emp b where a.deptno = b.deptno);

altertnate solution: select empno,ename,b.deptno,dname from emp a, dept b where a.deptno(+) = b.deptno and empno is null;

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**How to get 3 Max salaries ?**

select distinct sal from emp a where 3 >= (select count(distinct sal) from emp b where a.sal <= b.sal) order by a.sal desc;
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**How to get 3 Min salaries ?**

select distinct sal from emp a where 3 >= (select count(distinct sal) from emp b where a.sal >= b.sal);
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select distinct hiredate from emp a where &n = (select count(distinct sal) from emp b where a.sal >= b.sal);

**How to get nth max salaries ?**select distinct hiredate from emp a where &n = (select count(distinct sal) from emp b where a.sal >= b.sal);

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**Select DISTINCT RECORDS from emp table.**

select * from emp a where rowid = (select max(rowid) from emp b where a.empno=b.empno);
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**How to delete duplicate rows in a table?**

delete from emp a where rowid != (select max(rowid) from emp b where a.empno=b.empno);
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**Count of number of employees in department wise.**

select count(EMPNO), b.deptno, dname from emp a, dept b where a.deptno(+)=b.deptno group by b.deptno,dname;
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**Suppose there is annual salary information provided by emp table. How to fetch monthly salary of each and every employee?**
select ename,sal/12 as monthlysal
from emp;

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**Select all record from emp table where deptno =10 or 40.**
select * from emp where deptno=30 or
deptno=10;

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**Select all record from emp table where deptno=30 and sal>1500.**
select * from emp where deptno=30
and sal>1500;

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**Select all record from emp where job not in SALESMAN or CLERK.**
select * from emp where job not in
('SALESMAN','CLERK');

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**Select all record from emp where ename in 'BLAKE','SCOTT','KING'and'FORD'.**
select * from emp where ename
in('JONES','BLAKE','SCOTT','KING','FORD');

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**Select all records where ename starts with ‘S’ and its lenth is 6 char.**
select * from emp where ename
like'S_';

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**Select all records where ename may be any no of character but it should end with ‘R’.**
select * from emp where ename
like'%R';

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**Count MGR and their salary in emp table.**
select count(MGR),count(sal) from
emp;

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**In emp table add comm+sal as total sal .**
select ename,(sal+nvl(comm,0)) as
totalsal from emp;

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**Select any salary <3000 from emp table.**
select * from emp where
sal> any(select sal from emp where sal<3000);

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**Select all salary <3000 from emp table.**
select * from emp where
sal> all(select sal from emp where sal<3000);

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**Select all the employee group by deptno and sal in descending order.**
select ename,deptno,sal from emp
order by deptno,sal desc;

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**How can I create an empty table emp1 with same structure as emp?**
Create table emp1 as select * from
emp where 1=2;

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Select * from emp where sal>=1000 And sal<2000

**How to retrive record where sal between 1000 to 2000?**Select * from emp where sal>=1000 And sal<2000

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select * from emp where exists(select * from dept where emp.deptno=dept.deptno)

**Select all records where dept no of both emp and dept table matches.**select * from emp where exists(select * from dept where emp.deptno=dept.deptno)

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(Select * from emp) Union (Select * from emp1)

**If there are two tables emp1 and emp2, and both have common record. How can I fetch all the recods but common records only once?**(Select * from emp) Union (Select * from emp1)

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(Select * from emp) Intersect (Select * from emp1)

**How to fetch only common records from two tables emp and emp1?**(Select * from emp) Intersect (Select * from emp1)

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(Select * from emp) Minus (Select * from emp1)

**How can I retrive all records of emp1 those should not present in emp2?**(Select * from emp) Minus (Select * from emp1)

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SELECT deptno, sum(sal) As totalsal

FROM emp

GROUP BY deptno HAVING COUNT(empno) > 2

**Count the totalsa deptno wise where more than 2 employees exist.**SELECT deptno, sum(sal) As totalsal

FROM emp

GROUP BY deptno HAVING COUNT(empno) > 2