Transaction
Explore the concept of SQL transactions, which allow multiple SQL statements to be executed as a single unit that either fully succeeds or fails. Understand why transactions are critical to avoid data inconsistencies, especially in environments with multiple users. Learn how to start, commit, and roll back transactions in SQL, and gain insight into locking mechanisms and storage engine differences that affect concurrency and performance.
Transaction
A common online definition of a database transaction reads “A transaction symbolizes a unit of work performed within a database management system against a database, and treated in a coherent and reliable way independent of other transactions.” In simpler terms, think about taking a two-legged flight from Mumbai to New York. The first airline takes you from Mumbai to Dubai and the second takes you from Dubai to New York. The two flight legs represent portions of a transaction. You must travel both legs to reach your destination, but if immigration forbids you from taking the second leg of the flight you’d want to return back to Mumbai and not remain stranded at Dubai. A database transaction is similar. You either want all the actions within the transaction to complete or none at all. You don’t want a transaction to complete halfway through and then abort.
Need for Transactions
One may wonder why we need transactions. Well, whenever multiple users are interacting with a database it is possible for the actions of one user to interleave with ...