Explain ACID properties with examples.

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 ACID and Relational Databases

Four crucial properties define relational database transactions: atomicity, consistency, isolation, and durability-typically referred to as ACID. 

  • Atomicity defines all the elements that make up a complete database transaction or none.
  • Consistency defines the rules for maintaining data points in a correct state after a transaction. Isolation keeps the effect of a transaction invisible to others until it is committed, to avoid confusion. 
  • Durability ensures that data changes become permanent once the transaction is committed.

A Relational Database Example

Here is a simple example of two tables that a small firm may use to process product orders. The first table is a customer information table, which means that each entry contains a customer's name, address, shipping and payment information, phone number, and other contact information. Each piece of information (each attribute) is in its column, and each row is assigned a unique ID (a key) in the database. Each entry in the second table-a customer order table-includes the ID of the customer who made the purchase, the product ordered, the quantity, the size, and color are chosen, and so on-but not the client's name or contact information.

The only thing these two tables have in common is the ID column (the key). However, because of the shared field, the relational database may establish a link between the two tables. When the company's order processing application submits an order to the database, the database can go to the customer order table, pull the correct product order information, and use the customer ID from that table to look up the customer's billing and shipping information in the customer info table. The database system can then fetch the proper product, the client will receive the order on schedule, and the firm will be compensated.



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