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[Music]
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thank you
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[Music]
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Hello friends welcome back to our
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Channel
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so in today's session we'll discuss
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about two more commands in SQL that is a
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drop and truncate
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so a drop command is used to delete the
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complete table from the database whereas
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truncate command will delete the data
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from the table not the table the data
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from the table
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so let us see the syntax and then we'll
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execute the same in the SQL
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so the first one is a drop command and
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both are both comes under the data
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definition language commands Okay so
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drop command which is a ddl command
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and the syntax is
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drop
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table followed by table name so it will
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delete the complete table okay see here
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it deletes
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complete table
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from the database from the database so
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we know that the database consists of a
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lot of tables so in order to delete the
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table the syntax is drop table table
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name
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okay
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the ddl command and it deletes
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complete data from the table so the
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table will not be deleted but it will
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delete the data from the table so the
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Syntax for this one is a truncate
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table
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name
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table name right so let us execute these
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two commands in the MySQL so let us open
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the MySQL command line
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so it will prompt for the password so
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use the password
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I'll
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clear the screen now use the database
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YouTube because we are going we are
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using this YouTube and in this YouTube
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we are having the tables let us check
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tables so we are having only one table
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that is a student
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right so if you want to delete the data
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so let us check whether this one having
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the data or not so select start from
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student there is an empty table
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so let us insert some data so insert
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let us check the
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description
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so that will get the complete structure
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so we need to give all these values so
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I'll insert
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or or first let us see the drop table so
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drop
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table
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student so it will completely delete the
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table from the database see query okay
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zero rows affected and now you can see
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show databases or show tables so it will
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be an empty set because previously we
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are having a student table so in the
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YouTube database if you execute this
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issue tables command you will get the
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table student
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but we have deleted the table so if the
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table consists of data then also the
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table will be deleted the drop table
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table name will completely deletes the
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table from the database now once again
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we'll create a table and we'll check
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with the truncate function so create
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table
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student let us uh
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take some three attributes Sid which is
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of a integer s name
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which is of where care
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of authority
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and some percentage which is of a float
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and use a primary key it's not required
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but we'll use this one primary key as ID
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so a table has been created now if You
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observe short tables so there is a one
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table with a student so let us insert
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some values insert into student
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values so let us take 1 0 1
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Sandeep
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99
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so one row affected
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and see one zero two
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sarathi
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96 so again
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one zero three
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ramu
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sorry
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one zero three
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ramu
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with 93
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right so now you can select a star from
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student you can get the data so there
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are three rows now use a truncate method
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truncate table table name student so it
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will delete all the data from the table
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so you can observe the
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tables so the table exists okay the
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table will not be deleted so if you use
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a truncate command it will delete the
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data inside the table but not the table
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right so you can observe show tables
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still the student table is available
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here
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but what about the rows inserted in the
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student tables so select start from
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student it will be the empty set because
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all these through three rows will be get
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deleted
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for by using this truncate command
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right so hope you understood this one a
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simple commands drop to delete the table
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truncate to delete the data
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right so let's stop here so hope you
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understood this uh ddl comment so uh if
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you are having any doubts regarding this
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one feel free to post your doubts in the
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comment section definitely I will try to
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clarify all your doubts and if you
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really enjoyed my session like my
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session share my session with your
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friends and don't forget to subscribe to
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our Channel thanks for watching thank
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you very much