Oracle basics and opearators

Oracle basics and opearators
selecting all column
select * from emp;
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sql*plus command

sql>SET AUTOCOMMIT on
sql>SET AUTOCOMMIT 10
sql>set linesize 120
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sql>COLUMN ENAME HEADING 'EMPLOYEE |NAME'
sql>COLUMN SAL FORMAT $9,999,990.99
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****ACCOMODATING SQL COMMAND TO A FILE********

SQL>select empno,ename,sal from emp where job='&1'
SQL>save c:/job1.sql
SQL>START c:/job1.sql
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*****define a variable ************
sql>define rem='sal*12+nvl(comm,0)';
sql>select ename,job,&rem from emp order by &rem;
sql>undefine rem
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!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!operators!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

ARITHMETIC
select 12+3,13*4,14-5,16/4 from dual;
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CONCATENATION
select empno||'_'||ename employee, 'works in department' from emp;

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****null value******
select ename,sal*12+comm annual_sal from emp;

select ename,sal*12+nvl(comm,0) annual_sal
from emp;

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*****where clause and operators*******

select * from emp
where ename='SMITH'
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where deptno<20>sal
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where sal>=comm
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where sal between 1000 and 2000
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where mgr in(7902,7566,7788)
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where ename like 'S%'
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where comm is null
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where sal between 1000 and 2000 and job='CLERK'
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where sal between 1000 and 2000 or job='CLERK'
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*****distinct clause*****

select distinct deptno,job
from emp;

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****order by*******
select deptno,job,ename
from emp
order by deptno,sal desc;
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*******USER INPUT********
select * from emp where deptno=&Department_no

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