analytics-The-KEEP-clause.sql

REM Script: Analytics - The KEEP clause
REM SQL from the KISS (Keep It Simply SQL) Analytic video series by Developer Advocate Connor McDonald. This script is demonstrates the KEEP clause, a great way of picking up attributes related to an aggregate, but not within the GROUP BY clause. For exmaple, finding the lowest salary per department, but also collecting the details of the employee with that salary as well

droptable emp;

createtableemp ( 
EMPNO NUMBER(4) , 
ENAME VARCHAR2(10) , 
JOB VARCHAR2(9) , 
MGR NUMBER(4) , 
HIREDATE DATE , 
SAL NUMBER(7,2) , 
COMM NUMBER(7,2) , 
DEPTNO NUMBER(2) 
) ;

Insert into emp (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7369,'SMITH','CLERK',7902,to_date('17/DEC/80','DD/MON/RR'),800,null,20) ;

Insert into emp (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7499,'ALLEN','SALESMAN',7698,to_date('20/FEB/81','DD/MON/RR'),1600,300,30) ;

Insert into emp (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7521,'WARD','SALESMAN',7698,to_date('22/FEB/81','DD/MON/RR'),1250,500,30) ;

Insert into emp (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7566,'JONES','MANAGER',7839,to_date('02/APR/81','DD/MON/RR'),2975,null,20) ;

Insert into emp (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7654,'MARTIN','SALESMAN',7698,to_date('28/SEP/81','DD/MON/RR'),1250,1400,30) ;

Insert into emp (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7698,'BLAKE','MANAGER',7839,to_date('01/MAY/81','DD/MON/RR'),2850,null,30) ;

Insert into emp (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7782,'CLARK','MANAGER',7839,to_date('09/JUN/81','DD/MON/RR'),2450,null,10) ;

Insert into emp (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7788,'SCOTT','ANALYST',7566,to_date('09/DEC/82','DD/MON/RR'),3000,null,20) ;

Insert into emp (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7839,'KING','PRESIDENT',null,to_date('17/NOV/81','DD/MON/RR'),5000,null,10) ;

Insert into emp (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7844,'TURNER','SALESMAN',7698,to_date('08/SEP/81','DD/MON/RR'),1500,null,30) ;

Insert into emp (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7876,'ADAMS','CLERK',7788,to_date('12/JAN/83','DD/MON/RR'),1100,null,20) ;

Insert into emp (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7900,'JAMES','CLERK',7698,to_date('03/DEC/81','DD/MON/RR'),950,null,30) ;

Insert into emp (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7902,'FORD','ANALYST',7566,to_date('03/DEC/81','DD/MON/RR'),3000,null,20) ;

Insert into emp (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7934,'MILLER','CLERK',7782,to_date('23/JAN/82','DD/MON/RR'),1300,null,10) ;

commit


select deptno, min(sal) 
from emp 
group by deptno;

selectd.deptno, d.min_sal, e.empno
from emp e, 
 ( select deptno, min(sal) min_sal 
from emp 
group by deptno 
 ) d 
whered.deptno=e.deptno
ande.sal=d.min_sal;

select deptno, min(sal), 
min(empno) KEEP ( dense_rank FIRST order by sal) empno 
from emp 
group by deptno;