Design a database for Library system, the system contains many users that can borrow books, each user has his own profile that contains information about him, and there are categories to classify the books to ease searching for them

$($Note that: the user must pay for each borrowing operation$).$

$1-$ Draw the ER$-$Diagram or Schema diagram for the previous scenario.

$2-$ Create all the required tables for the system.

$3-$ Add $3$ records for each table using DML commands.

a$.$ Delete all users whom ages less than $15$ years old by calculating the age.

b$.$ And then, make sure users are older than $15$ years by checking the birthdate.

$4-$ Add Boolean column to check if the user returns the book.

$5-$ Update author name in book table to be always initial capital.

$6-$ Modify $1$ of the tables name using DDL commands.

$7-$ Modify $2$ columns name with their datatypes using DDL commands.

$8-$ Create another userInfo table with some data, and then merge the data from user table by committing the following rules:

a$.$ When data matched: update the data in user table to be exact the same as userInfo table.

b$.$ When not matched: insert a new record in user table with data existed in userinfo table.