SQL Tutorial - 18: Logical Operators (Part-2) Video Lecture | Microsoft SQL for Beginners - Database Management

hello guys welcome to my channel this is
the 18th tutorial in this course and in
this tutorial we are going to talk about
the remaining logical operators that we
checked out in the PowerPoint in the
last tutorial but we did see in action
in the MySQL environment right so the
the logical operators that we are going
to talk about are in between and all
right so let's check out the in operator
first let's say you want to find out
details of all employees who have age
equal to 28 or 30 or 36 right and the
weigh-in is going to enable you to do
this is you have to first type in the
keyword select oops wait a second let me
get my cursor in the area done one so
select and then star because we are
pulling data out from all columns and
then the from keyword and the name of
the table which is employee and then on
the next line you type in the where
keyword and then the column one which
you want to apply the in operator so
that would be in this case age and then
you type in in and then within
parenthesis you type in a value list
right so age is a field that holds
numeric values so you do not have to
place the values that you are going to
put in this in the parentheses within
single quotes so you know if you want to
find out details with employees with age
28 put 28 there and if you want to find
out details of employees with a is 30
all you have to do is put in a comma
here and then the value which is 30 and
if you also want to find out details of
employees with age 36 you type in 36 to
write in at the end of the parentheses
you put in a semicolon determinate the
statement press ctrl enter and there you
go you would see that in the results
that we get to records you know andy
with ID 1911 has a is 28 and pete with
ID 1913 has a is 36 so there is no
employee in the table that has h 13
right so this is what the in operator
allows you to do you know you can have a
list of values between parenthesis and
the age you know the values in the age
field in the table would be compared to
the values that are there in the less
one by one right so for the first record
the valuing age would be compared to the
values in the list 28 30 or 36 if the
value matches with any of these values
and it would appear in the result set
otherwise it would be skipped so next
we're going to check out the between
operator now let's say in this query you
do not want to you know find out only
the employees that have age equal to
these three values but you want to find
out details of all employees that have
aged between 28 and 36 right so even if
the age is 31 you want that employ to be
in the result set
D is 34 you want an improbably in the
result set so you know to do that you
have to use the between keyword and I
let the you know first part of the query
be the same you know I just make
modifications in the last you know line
line number 3 so where you type in age
again and then you type in the keyword
between right and then you type in the
first value which in this case would be
28 and then you type in the keyword and
right and the final value which is 36 so
this is going to result into all records
that have the value for the age field
between 28 and 36 and when I press
control enter I see that this time the
result set is much more elaborated it's
got lot of records
so Howard with age 29 also appears in
the result set now because the age of
Howard is 29 and that's between 28 and
36 and you also see Shane with 33 and E
with 28 Jim with 34 Pete for 36 Kurt
with 34 and I missed Roger by 32 right
so that's about the between keyword the
next keyword that we're going to talk
about is a little difficult for me to
explain you know it's the all operator
and you know what it does is I'm going
to explain that I'm going to explain the
all operator to you you know with the
help of an example so let's say you want
to find out details of all employees
whose age is less than the age of all
employees who have a salary greater than
you know let's say 20,000 right so the
condition you know just focus on the
condition part you know what all
constraints are you imposing through the
in addition so I'll repeat the condition
again you want to find out details of
all employees who have aged less than
the age of all employees or the ages of
all employees who have salary you know
greater than 20,000 so the query that is
going to be you have to use select and
star obviously because you're pulling
out you know details all from all fields
and then you're going to type in the
from keyword name the table and then you
type in the where keyword and you type
in the age field right because the
constraint starts with age you want to
you know impose your constraint on the
age field that's that's where your
condition is sort of based on so you
want to find out details of employees
who have age less than the age of all
employees and and this condition has to
be in parentheses right so you use
select again and some people would say
this is a you know a sub-query but you
know you have to use the all operator
here so you know it's it's more like a
demonstration of the all operator then
you know you know an example of
sub-query and we're going to talk about
sub-queries later on in the course in
more detail but for the time being just
know that you have to you know achieve
this sort of a thing in this way so
select age from employee right and I'll
put this in capital letters because it's
an SQL keyword and then you type in the
last part of the condition where salary
is greater than 20,000 putting a
semicolon at the end to terminate the
statement and there you go you see that
in the result set we get only one row
and this is for Philip with ID 1910 so
the age of Philip is 20 and the age of
Philip is less than the age values of
all rows that are returned by this way
right so if you would execute this query
independently let me show you guys what
the result set is alright so I'll paste
it here put a semicolon and when I press
control enter you see that you get all
these values you know 20
9 25 27 21 33 34 36 23 24 and 27 so you
know Phillip is the only employee you
know who has a value for age that's less
than the values that are returned by
this way and this is the second part of
the condition that we spoke about you
know when I mentioned the condition to
you right so that's all about logical
operators in case you guys have any
doubts then you can put in your comments
in the comment box below and I'm going
to try to reply to as many as I can and
please subscribe to my channel in case
you haven't already and I'm going to see
you guys in the next tutorial which will
discuss something interesting and
important again so see you