SQlite_master is the master table which holds the key information about your database tables.

The fetchall() method is used to fetch all rows from the database table.
result = cursor. fetchall()

If a column of a table is declared to be an INTEGER PRIMARY KEY, then whenever a NULL is used as an input for this column, the NULL will be automatically converted into an integer which will be one larger than the highest value so far used in that column.

Users of database can be human users or programmers, other programs or applications.

(i) DISTINCT
(ii) WHERE
(iii) GROUP BY
(iv) ORDER BY.
(v) HAVING

Program: Display the records in descending order using python script
import mysqldb
db = mysqldb.connect ("local host", "user", "123", "organization")
cursor = db.cursor()
cursor.execute ("SELECT *FROM Employee ORDER BY Name DESC")
result = cursor.fetchall()
for row in results:
ENO = row[0], EmpName = row[1], EmpDept = row[2]
print ENO, EmpName, EmpDept
db.close()

(i) SQLite is a simple relational database system, which saves its data in regular data files or even in the internal memory of the computer.
(ii) It is designed to be embedded in applications, instead of using a separate database server program such as MySQL or Oracle.
Advantages:
SQLite is fast, rigorously tested, and flexible, making it easier to work.
Python has a native library for SQLite.

(i) Program to Display Name, city and Item Name of suppliers who do not reside in Delhi:
import mysqldb
db = mysqlkdb.Connect ("Supplier.db")
cursor = db.cursor()
cursor. execute ("'SELECT NAME, CITY, ICode FROM Supplier WHERE CITY <> "Delh")
db. commit()
result=cursor.fetchall()
print ("result, sep = "\n")
db. close()
(ii) Program to Increment the suppQty of Akila by 40:
import mysqldb
db = mysqldb.Connect ("ltem.db"')
cursor = db.cursor()
cursor. execute ("UPDATE Item SET Name = 'Akila' WHERE SuppQty = 235)
db. commit()
cursor. execute ("SELECT * FROM Item")
result = cursor.fetchall()
print ("result, sep ="\n")
db. close()

HAVING clause is used to filter data based on7the group functions. This is similar to WHERE condition but can be used , only with group functions. Group functions cannot be used in WHERE Clause but can be used in HAVING clause.
Example:
import sqlite3
connection = sqlite3.connect("Academy.db")
cursor = connection.cursorO
cursor.execute("SELECT GENDER,COUNT(GENDER) FROM Student GROUP BY GENDER HAVING COUNT( GENDER> 3")
result = cursor.fetchall( )
co = [i[o] for i in cursor. description]
print(co)
print(result)
Output:
['gender', 'COUNT(GENDER)']
[('M', 5)]

(i) SQLite is a simple relational database system, which saves its data in regular data files or even in the internal memory of the computer.
(ii) It is designed to be embedded in applications, instead of using a separate
database server program such as MySQL or Oracle.
(iii) SQLite is fast, rigorously tested, and flexible, making it easier to work. Python
has a native library for SQLite.
To use SQLite,
Step 1: import sqlite3
Step 2: create a connection using connect() method and pass the name of the database file
Step 3: Set the cursor object cursor = connection. cursor()
(iv) Connecting to a database in step 2 means passing the name of the database to be accessed. If the database already exists the connection will open the same. Otherwise, Python will open a new database file with the specified name.
(v) Cursor in step 3 is a control structure used to traverse and fetch the records of the database.
(vi) Cursor has a major role in working with Python. All the commands will be executed using cursor object only.
(vii) To create a table in the database, create an object and write the SQL command in it.
Example: sql_comm = "SQL statement"
(viii) For executing the command use the cursor method and pass the required sql command as a parameter. Many number of commands can be stored in the sql comm and can be executed one after other.
(ix) Any changes made in the values of the record should be saved by the commend "Commit" before closing the "Table connection" .