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    PRIMARY KEY constraint: The Primary key constraint uniquely identifies each record in a table.
     Primary keys must be unique, cannot be NULL and only one primary key can exists per table.         QR QUEST

       FOREIGN  KEY  constraint:  The  Foreign key  constraint  is used  to  establish a relationship   Visit the given link
     between two tables. It ensures that the values in a column in one table match the values in the   to learn about Constraints
     primary key column of another table.                                                             in SQL:
                                                                                          https://www.youtube.com/watch?v=-
       UNIQUE constraint: The Unique constraint ensures that each value in a column is unique.      8bYtApJNos
                                                                                         Answer the given questions:
       DEFAULT constraint: The Default constraint is used to specify a default value for a column.
     If no other value is specified, the default value will be added to all new records.  1.  Why are constraints important
                                                                                           in a database?
       CHECK constraint: The Check constraint restricts the range of values that can be stored in a   2.  Explain any two SQL
     column by enforcing a specified condition.                                             constraints.

     RAPID RECALL  Tick ( ) if you know this.  USING DATABASE

                     To work with a specific database, you must first select it using the
     1.  Arithmetic operators perform basic mathematical operations on numerical data.   USE command. The syntax is as follows:

     2.  DML is a language that enables users to retrieve, update, insert and delete data.   USE database_name;

                     DELETING DATABASE

                     If  you  no longer need  a database,  you  can delete  it.  However, this  action  is  permanent  and

     CREATING, VIEWING AND DELETING A DATABASE  removes all tables and data within the database. Always ensure that you have a backup before
                     deleting a database.

     Creating, viewing and deleting are basic database management tasks. They help set up new   The syntax to delete a database is:
     databases, check existing ones and remove those that are no longer needed.
                     DROP DATABASE database_name;
     CREATING DATABASE

     The CREATE DATABASE command is used to create a database in MySQL. Once the database is   CREATING AND MANAGING TABLES
     created, you can begin adding tables, storing data and running queries.

     The syntax to create a database is:   In  MySQL, tables  are the fundamental  building blocks  of a database  for storing  data  in an
                     organised mannner. Table management involves creating, viewing, modifying and deleting these
     CREATE DATABASE database_name;
                     structures as needed.
     The command to create a School database is as follows:
                     CREATING TABLES
                     A table, also known as a relation, organizes data into rows and columns. To create one, you use
                     the CREATE TABLE command. The syntax is as follows:

                     CREATE TABLE table_name
                     (

     VIEWING DATABASE  column_name1 data_type(size),
                     column_name2 data_type(size),
     To view a list of existing databases, the following command is used:
                     column_name3 data_type(size),
     SHOW DATABASES;  .....

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                                                                                              MySQL: My First Database

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