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Displaying A record using fetchone( )

The fetchone( ) method returns the next row of a query result set or None in case there is no row left.

Example

import sqlite3

connection= sqlite3 ,connect(“Academy.db”)

cursor = connection.cursor( )

cursor.execute(“SELECT * FROM student”) 

print(“\nfetch one:”) 

res = cursor. fetchone( )

print(res)

OUTPUT

fetch one:

(1, ‘Akshay’ , ’B’ , ’M’ , 87.8, ‘2001-12-12’) 

Displayingusing fetchmany( )

Displaying specified number of records is done by using fetchmany( ).This method returns the next number of rows (n) of the result set. 

Example : Program to display the content of tuples using fetchmany( )

import sqlite3

connection = sqlite3.connect(” Academy, db”) 

cursor = connection. cursor( ) 

cursor.execute(“SELECT * FROM student”) 

print(“fetching first 3 records:”)

result= cursor. fetchmany(3)

print( result)

OUTPUT

fetching first 3 records:

[ (1, ‘Akshay’ , ’B’ , ‘M’ , 87.8, ‘2001-12-12’), (2, ‘Aravind’ , ‘A’ , ’M’ , 92.5, ‘2000-08-17’), (3, ‘BASKAR’, ‘C, TVT, 75.2, ‘1998-05-17’)]

(b) fetchmany( )

qmarkstyle, namedstyle

cursor. fetchall( ) - fetchall ( )method is to fetch all rows from the database table cursor.

fetchone( ) – The fetchone ( ) method returns the next row of a query result set or None in case there is no row left.

cursor.fetchmany( ) method that returns the next number of rows (n) of the result set.

Answer (c) Commit

The ORDER BY Clause can be used along with the SELECT statement to sort the data of specific fields in an ordered way. It is used to sort the result-set in ascending or descending order. In this example name and Rollno of the students are displayed in alphabetical order of names.

Example

import sqlite3

connection= sqlite3.connect(“Academy.db”)

cursor = connection.cursor( ) 

cursor.execute(“SELECT Rollno,sname FROM student Order BY sname”)

result = cursor.fetchall( )

print(*result,sep= ” \n”)

OUTPUT

(1, ‘Akshay’)

(2, ‘Aravind’)

(3, ‘BASKAR’)

(6, ‘PRIYA’)

(4, ‘SAJINI’)

(7, ‘TARUN’)

(5, ‘VARUN’)

1. COUNTO 

2. SUM( ) 

3. MIN( ) 

4. AVG( ) 

5. MAX( )

To populate (add record) the table “INSERT” command is passed to SQLite. “execute” method executes the SQL command to perform some action. In most cases, you will not literally insert data into a SQL table. You will rather have a lot of data inside of some Python data type e.g. a dictionary or a list, which has to be used as the input of the insert statement.

import sqlite3

connectoin = sqlite3.connect(“company.db”) cursor = connection.cursor() cursor.execute(“Select * from product”)

print(“Displaying Records”) result = cursor.fetchmany(5)

print(*result, Sep = “\n”) 

Output:

Displaying records (1003, ‘Scanner’ , 10500) 

(1004, ’Speaker’ , 3000)

(1005, ‘Printer’ , 8000)

(1008, ’Monitor’ , 15000)

(1010, ‘Mouse’ , 700)

input( ) is used to accpet data during run time in python.

(b) order by

1. import sqlite3

connection = sqlite3.connect(“ABC.db”)

cursor = connection,cursor( ) 

cursor.execute(“SELECT Supplier.Name, Supplier.city,

Item.ItemName FROM Supplier, Item

where Supplier.Icode = Item.Icode AND Supplier.city NOT IN ‘Delhi'”)

co=[i[0] for i in cursor.description]

print(co)

result = cursor. fetchall( )

for r in result:

print(r)

Output:

[‘Name’ , ‘City’ , ‘ItemName’]

[‘Anu’ , ‘Bangalore’ , ‘Mouse’]

[‘Shahid’ , ‘Bangalore’ , ‘Monitor’]

[‘Akila’ , ‘Hydrabad’ , ‘Printer’]

[‘Girish’ , ‘Hydrabad’ , ‘Scanner’]

[‘Shylaja’ , ‘Chennai’ , ‘Monitor’]

[‘Lavanya’ , ‘Mumbai’ , ‘Printer’]

2. Increment the suppQty of Akila by 40 import sqlite3 connection = sqlite3.connect(“ABC.db”) 

cursor = connection.cursor( ) 

cursor.execute(“UPDATE Supplier SET SuppQty = 

SuppQty + 40 where Name = ‘Akila'”) 

cursor.commit( )

result = cursor. fetchall( )

print(result)

connection.close( )

Output:

(S004, ‘Akila’ , ‘Hydrabad’ , 1005, 235)

Having clause is used to filter data based on the 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. cursor( )

cursor.execute(“SELECT GENDER,COUNT(GENDER) FROM Student GROUP BY GENDER HAVING COUNT(GENDER)>3 “)

result = cursor. fetchall( )

co= [i[0] for i in cursor, description]

print(co)

print( result)

OUTPUT

[‘gender’ , ‘COUNT(GENDER)’]

[(‘M’ , 5)]

MIN( ) function returns the smallest value of the selected columns

(d) group by

cursor description

Answer is (d) none

(c) both are true

(a) Execute( )

(a) Fetch ne( )

(a) R is the reason for A

Given:

Student → Table Rollno, Sname, grade, gender, average, birth-date

Appointment → rollno, duty, age

Example

import sqlite3

connection = sqlite3.connect(“Academy.db”) cursor = connection.cursor( )

cursor.execute(“””DROP TABLE Appointment;”””) sql_command = “””

CREATE TABLE Appointment(rollnointprimarkey,Dutyvarchar(10),age int)”””

cursor.execute(sqlcommand)

sql command – ‘””INSERT INTO Appointment (Rollno,Duty ,age)

VALUES (“1” , “Prefect” , “17”);”””

cursor, execute(sql_command)

sql_command = ”””INSERT INTO Appointment (Rollno,Duty, age)

VALUES (“2” , “Secretary” , “16”);””” 

cursor.execute(sql_command)

# never forget this, if you want the changes to be saved:

connection.commit( )

cursor.execute(“SELECT student.rollno,student.sname,Appointment. 

Duty,Appointment.Age FROM student,Appointment where student.

rollno= Appointment.rollno”)

#print (cursor.description) to display the field names of the table

co= [i[0] for i in cursor.description] print(co)

# Field informations can be readfrom cursor.description.

result = cursor. fetchall( )

for r in result:

print(r)

OUTPUT

[‘Rollno’, ‘Sname’ , ‘Duty’ , ‘age’]

(1, ‘Akshay’ , ‘Prefect’ , 17)

(2, ’Aravind’ , ’Secretary’ , 16)

In this example we are going to accept data using Python input() command during runtime and then going to write in the Table called “Person”

Example

# code for executing query using input data

import sqlite3

#creates a database in RAM

con =sqlite3.connect(“Academy,db”)

cur =con.cursor( )

cur.execute(“DROP Table person”) 

cur.execute(“create table person (name, age, id)”) 

print(“Enter 5 students names:”)

who =[input( ) for i in range(5)]

print(“Enter their ages respectively:”)

age =[int(input()) for i in range(5)]

print(“Enter their ids respectively:”)

p_d =[int(input( ))for i in range(5)]

n =len(who)

for i in range(n):

#This is the q-mark style:

cur.execute(“insert into person values(?,?,?)” , (who[i], age[i], p_id[i]))

#And this is the named style:

cur.execute(“select *from person”)

#Fetches all entries from table

print(“Displaying All the Records From Person Table”)

print (*cur.fetchall(), sep= ’\n’)

OUTPUT

Enter 5 students names:

RAM

KEERTHANA

KRISHNA

HARISH

GIRISH

Enter their ages respectively:

28

12

21

18

16

Enter their ids respectively:

1

2

3

4

5

Displaying All the Records From Person Table 

(‘RAM’ , 28, 1)

(‘KEERTHANA’ , 12, 2)

(‘KRISHNA’ , 21, 3)

(‘HARISH’ , 18,4)

(‘GIRISH’ , 16, 5)

You can specify the mode while opening a file. In mode, you can specify whether you want to read ‘r’ , write ‘w’ or append ‘a’ to the file. You can also specify “text or binary” in which the file is to be opened. The default is reading in text mode. In this mode, while reading from the file the data w’ould . be in the format of strings.

Select SQL is used to retrieve or fetch data from a table in the database.

Answer is (d) Master

(b) fetchall( )

Database Management System

import sqlite3

con= sqlite3 .connect(‘Academy.db’)

cursor = con.cursor( )

cursor.execute(“SELECT name FROM sqlitemaster WHERE type-table’;”)

print(cursor. fetchall( ))

OUTPUT

[(‘Student’ ,), (‘Appointment’ ,), (‘Person’ ,)]

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

Correct option is (d) Molality

The cube root of a number n is the number whose cube is n. It is denoted by \(\sqrt[3] {n}\), e.g., \(\sqrt[3]{8}\) = 2.

Given: Total surface area of cube = 864 sq. cm 

To find: Volume of cube 

Solution:

i. Total surface area of cube = 6l² 

∴ 864 = 6l² 

∴ l² = \(\sqrt[864]6\)

∴ l² = 144

∴ l = \(\sqrt{144}\)… [Taking square root on both sides] 

= 12 cm 

ii. Volume of cube = l²

 = 12³

= 1728 cubic cm. 

∴ The volume of cube is 1728 cubic cm.

The cube root of a number can be found by resolving the number into prime factors, making groups of 3 equal factors, picking out one of the equal factors from each group and multiplying the factors so picked.

1728 = \(\underline{2\times2\times2}\) x \(\underline{2\times2\times2}\) x \(\underline{3\times3\times3}\)

\(\sqrt[3] {1728}\) = 2 x 2 x 3 = 12

The cube root of a negative perfect cube is negative, e.g.,\(\sqrt[3] {-125}\) = -5

For any integer a and b, we have

(i) \(\sqrt[3] {a \times b}\) = \(\sqrt[3] {a} \times\sqrt[3]{b}\)

(ii) \(\sqrt[3]{\frac{a}{b}}\) = \(\frac{\sqrt[3] {a}}{\sqrt[3]{b}}\)

(b) 0.2

\(\sqrt[3]{\sqrt{0.000064}}\) = \(\sqrt[3]{\sqrt\frac{64}{1000000}}\) 

\(\sqrt[3]{\frac{8}{1000}}\) = \(\frac{2}{10}\) = 0.2

(b) 125³

Let the number be x. Then,

\(\frac{\sqrt[3]X}{5}\) = 25 \(\Rightarrow\) \(\sqrt[3]{X}\) = 125 \(\Rightarrow\) x = (125)³

(d) 64

\(\sqrt[2]{\sqrt[3]{X\times0.000001}}\) = 0.2

\(\Rightarrow\) \(\sqrt[3]{X \times 0.000001}\) = (0.2)²

= 0.04 (Squaring both the sides)

\(\Rightarrow\) x x 0.000001 = (0.04)³ = 0.000064 (on taking the cube of both the sides)

\(\Rightarrow\) x = \(\frac{0.000064}{0.000001}\) = 64.

(c) \(a^{\frac{1}{3}}\)

\(\sqrt[3]{\sqrt[3]{a^3}}\) = \(\big((a^3)^{\frac{1}{3}\big)^{\frac{1}{3}}}\) = \(a^{3\times\frac{1}{9}}\) = \(a^{\frac{1}{3}}\)

When we are in a strange place. Our body language comes to our help. We have to mime them and express what we feel or what we do, some situations require body gestures some times our actions reflect our inner strengths and our own personality. Sometimes we have to use signs and smybols with all these things we communicate.

The poet asks us not to let die the thought.

English plays an important role in communicating with any people throughout the world. Through it the world wide knowledge can be gained. It is a wonderful game in matching the words to the brightest thoughts in our head. So that they come out and true. They brush our wrong ideas and feed our thoughts to become the loveliest things.

(c) tetracycline