MYSQL DROP to remove Column,Table,DataBase
We have seen how to remove records from a table by using truncate sql command. Now we will learn how to use DROP query command to delete a table or a field or some other properties associated with the table. Let us start with deleting a field by DROP command.
Deleting a Colunm of a Table
ALTER TABLE USER DROP UserType ;
Here user is our table name and usertype is one of the field of this table. By this command we can delete the field usertype of the table User.
Deleting a Table
We can use DROP command to remove a table inside the database. Now here is the code to delete the table User.
DROP TABLE USER
Checking before deleting
We can check whether table is there or not before giving any delete command. Without ensuring the presence of table ( non existence table ) delete command will generate an error message.
DROP TABLE IF EXISTS USER ;
Deleting multiple tables
We can use drop command to delete more than one table. Here is the command to remove 4 tables.
DROP TABLE User,New_User,City,State;
The above command will delete four tables.
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