Skip to main content

Schedule in DBMS

Schedule

A series of operation from one transaction to another transaction is known as schedule. It is used to preserve the order of the operation in each of the individual transaction.

Schedule in DBMS


1. Serial Schedule
The serial schedule is a type of schedule where one transaction is executed completely before starting another transaction. In the serial schedule, when the first transaction completes its cycle, then the next transaction is executed.

For example: Suppose there are two transactions T1 and T2 which have some operations. If it has no interleaving of operations, then there are the following two possible outcomes:
  1. Execute all the operations of T1 which was followed by all the operations of T2. 
  2. Execute all the operations of T1 which was followed by all the operations of T2. 

  • In the given (a) figure, Schedule A shows the serial schedule where T1 followed by T2.
  • In the given (b) figure, Schedule B shows the serial schedule where T2 followed by T1.

2. Non-serial Schedule
  • If interleaving of operations is allowed, then there will be non-serial schedule.
  • It contains many possible orders in which the system can execute the individual operations of the transactions.
  • In the given figure (c) and (d), Schedule C and Schedule D are the non-serial schedules. It has interleaving of operations.

3. Serializable Schedule
  • The serializability of schedules is used to find non-serial schedules that allow the transaction to execute concurrently without interfering with one another. 
  • It identifies which schedules are correct when executions of the transaction have interleaving of their operations.
  • A non-serial schedule will be serializable if its result is equal to the result of its transactions executed serially.

Schedule in DBMS

Schedule in DBMS

Schedule in DBMS

Schedule in DBMS



Here,

Schedule A and Schedule B are serial schedule.

Schedule C and Schedule D are Non-serial schedule.

Comments

Popular posts from this blog

Natural Language Processing (NLP)

What is Natural Language Processing (NLP) ? Natural Language Processing (NLP)* is a field of artificial intelligence (AI) that focuses on the interaction between computers and humans using natural language. It involves the development of algorithms and models that enable computers to understand, interpret, and generate human language. Here are key aspects of NLP: 1. *Text Understanding:* NLP systems aim to comprehend the meaning of written or spoken language. This involves tasks such as text classification, sentiment analysis, and named entity recognition. 2. *Speech Recognition:* NLP extends to processing spoken language, converting audio signals into text. This technology is used in voice assistants, transcription services, and more. 3. *Language Generation:* NLP systems can generate human-like text. This is employed in chatbots, language translation services, and content generation. 4. *Machine Translation:* NLP is fundamental to machine translation systems that enable the automatic...

Implement a ping server program using TCP socket

Implement a ping server program using a TCP socket Server-side import java.net.*; import java.io.*; import java.net.SocketException; import java.util.*; import java.lang.*; class pingtcpserver { public static void main(String args[]) throws Exception { ServerSockets=null; Socketsoc=null; String smsg=""; PrintWriter pw; try { s=new ServerSocket(5219); System.out.println("Connecting with client ....... "); soc=s.accept(); System.out.println("Connection Established"); BufferedReader brin=new BufferedReader(new InputStreamReader(soc.getInputStream())); for(int i=0;i<5;i++) { pw=new PrintWriter(soc.getOutputStream(),true); smsg=brin.readLine(); if(i==3) Thread.sleep(100); pw.println(smsg); }} catch(SocketException e) { System.out.println(e); } finally { s.close(); soc.close(); }}} Client-side import java.io.*; import java.net.*; import java.net.SocketException; import java.util.*; class pingtcpclient { public static void main(String args[]) throws Exception ...

JS Code for Generating OTP

JS Code for Generating OTP -  * Learn how to create a simple JavaScript function to generate a random 4-digit OTP. (GENERATED BY - ChatGPT) function OTP() { let otp = ""; otp = Math.floor(Math.random() * 9000 + 1000); return otp; } console.log("Your OTP is-", OTP());