SQL Tutorial - 48: Views in SQL (Part-1) Video Lecture | Microsoft SQL for Beginners - Database Management

hello guys welcome to my channel this is
the 48 tutorial in this course and in
this tutorial we are going to talk about
views and this is going to be your short
tutorial I'm just going to briefly
introduce what views are in SQL and the
views are basically virtual tables that
you might want to use when you want to
limit the information that you display
to your table viewers right and
essentially a view is nothing but an SQL
query that has a name and every time you
use a view you basically execute that
query right so what I'm going to do is
you know just demonstrate how you create
a view in this tutorial and then in the
next couple of tutorials we're going to
work with views you know see the various
kinds of operations that you can perform
on views and why exactly are views
useful you know we understand that in
this tutorial of bed and then a bit more
in the next tutorials so I've got a
table in one of the databases and I have
on the system it's called employee so
I'm just going to show you the data that
I have in a table first so to do that
I'll type in select star from employee
and when I execute the query I see that
it's got a you know lot of information
you know there's ID field and then name
age email and salary and then the ID
field I guess is the primary key for the
table and it takes in values from 1900
to 1916 so there are about what 17 rows
in the table at the moment so you know
let's say you want to display some
information from this table but you know
you do not want to display like all the
information you want to display you know
let's say the employee IDs and names and
email addresses you do not want to
display the age values or the salary
values and you know let's not just talk
about demonstration here in fact you
know if you want to have a structure
that contains only these three fields
from this table and does not contain the
age values or the salary values so
basically you want these values to be
abstracted or hidden from some users on
the system right so in that case it'll
be a you know sensible to have some kind
of a win
no that only lets you see through these
fields and doesn't let you see through
these fees and that window is what you
call a view in SQL so to create a view
for this table what I'll have to do is
type in the create view statement right
so you type in create and then view just
as we did for create table and then give
a space and type in a name for your view
so I'm going to call my view EMP
underscore view and you should try to
make your view names you know sort of
you know understandable in the sense
that I'm working with the employee table
in this tutorial so I have you know
picked up the first three alphabets from
the table and then the underscore symbol
and then view now this is not a
convention or this is not something that
you should do for all tables but then
you should have some kind of you know
link between the names of your views and
the names of your tables and then you
give a space and type in the keyword as
and this is something that we don't do
with Create table but we have to do with
the create view statement and then on
the next line you type in select and
then just select the columns that you
want your view to have so in this case I
want the view to work with the ID field
and the name field and then the email
field right so I'll type in these three
field names and then I'll type in from
and then the name of the table which is
employee and then you can also have a
where clause this is optional and I'm
going to have a wear condition like wear
name is not null right so if you pull
out information from this view then it's
going to get stuff from this table only
for those rows for which the name value
is not null right and in this table
currently I don't have any such row but
then in the next tutorial we'll maybe
add a row to this table that'll have a
null value for the name field and we
will see that that row is not returned
when you you know run a select star on
the view so when I execute this I see
that in the output I get the message
create view EMP underscore view as blah
blah blah has been executed successfully
because I see this green you know
amazing looking circle with a white
check and then I also get in the message
box that
rows were affected right because I've
just created my view yet and if suppose
I wanted to see how I can pull out stuff
from the view I'll type in select star
from EMP underscore view and when I
execute this statement I see that I only
get these three field names and I see
all the rows that I saw with the select
star from employee query and that's
because you know all rows in the
employee table currently satisfy the
condition that I had in the where clause
or when I created my view and the
condition was that the name should not
be null and there is no row in the
employee table that you know objects
that condition so that's it in this
tutorial I'll see you in the next one in
which we will see how we can insert
values in a table through you know views
and then you know some more stuff about
views interesting stuff I show you that
and thank you so much for watching this
one and you may subscribe to my channel
if you haven't already and I'll see you
soon