NCERT Solutions for Class 12 Computer And Communication Technology Computer Science With Python Chapter 7 Data File Handling

Write a method in Python to read lines from a text file DIARY.TXT, and display those lines, which are starting with an alphabet ‘P’.

Considering the following definition of class COMPANY, write a method in Python to search and display the content in a pickled file COMPANY.DAT, where CompID is matching with the value ‘1005’.

class Company:
	def __init__(self,CID,NAM):
	self.CompID = CID 	#CompID Company ID
	self.CName = NAM 	#CName Company Name
	self.Turnover = 1000
	
	def Display(self):
		print self.CompID,':',self.CName,':',self.Turnover

Observe the following table MEMBER carefully and write the name of the RDBMS operation out of (i) SELECTION (ii) PROJECTION (iii) UNION (iv) CARTESIAN PRODUCT, which has been used to produce the output as shown in RESULT. Also, find the Degree and Cardinality of the RESULT.

Differentiate between the following:

1. f = open(‘diary.txt’, ‘r’)
2. f = open(‘diary.txt’, ‘w’)

Write a method in python to read the content from a text file diary.txt line by line and display the same on screen.

Consider the following definition of class Member, write a method in python to write the content in a pickled file member.dat.

class Member:
	def_init_(self,Mno,N) :
	self.Memno=Mno
	self.Name=N
	def Show(self):
		Display (self.Memno, '#',self.Name)
	def store_data(self):
		piFile = open('member.dat','wb')
		pickle.dump(self, piFile)
		piFile.close()