Page 5 - Simple Queries in SQL

Selecting content of some columns
 select ename, job, hiredate from employee;
Command to select data of some columns

Ordering of columns
The column headings in the output table of a SQL command is in the same order as that of select
command, nothing changes in original table.

select ename, hiredate, job from employee;

.

To display data from all the columns:
Syntax: select * from table_name;
Select * from employee;

ALL/DISTINCT Clause
Distinct eliminates duplicate/redundant rows.

 Select [ALL | DISTINCT] <col list> from table;
(default is ALL)

select distinct job
from employee;
select job from employee;
(is equivalent to)
select ALL job from employee;