In a Database Management System (DBMS), “instance” and “schema” are two fundamental concepts that are as essential as the foundation and blueprint of a building. Let’s explore these concepts in a way that’s easy to understand. What is Instance? Storing data collection in a database at a particular moment in time is called an instance. … Read more
Data redundancy is a situation in which there are multiple copies of the same data stored at different places in the database. For example: When a customer came to a shop to buy something, and shop owner notes down the list of item every time and generate a bill for each product. Then this is … Read more
Undo/Redo is a database transaction log for handling transaction crash recovery. This algorithm stores all the values and changes made during transactions in a separate memory in case of failure or crash. It utilizes the stored value to restore the loss due to failure. This algorithm is a combination of two approaches UNDO: It stands … Read more
Timestamp ordering is a unique value given to every transaction whenever it comes into the system to execute. There are two types of timestamp values Read timestamp: It is the value of the last transaction which successfully performed the read operation. Write timestamp: It is the value of the last transaction which successfully performed the … Read more
The locking technique uses a lock that guarantees the exclusive use of data of transactions. The lock is used to restrict different transaction which is executing at the same time. There are 3 phases of Locking technique Taking the lock control and accessing the data of the transaction Complete the transaction execution Release lock There … Read more
The transaction is executed as a single unit and should be atomic, consistent, isolated, and durable. This ACID property of transaction maintains the integrity of the data during the execution of the database. What is Transaction in DBMS? In a Database Management System (DBMS), a transaction is a series of operations or steps that are … Read more