ACID properties provide a mechanism to ensure correctness and consistency of a database in a way such that each transaction is a group of operations that acts a single unit, produces consistent results, acts in isolation from other operations and updates that it makes are durably stored.
Atomicity
The atomicity means either all the operations (insert, update, delete) inside a transaction take place or none. Or you can say, all the statements (insert, update, delete) inside a transaction are either completed or rolled back. There is no midway i.e. transactions do not occur partially. Atomicity is also known as the ‘All or nothing rule’.
Consistency
Consistency refers to the correctness of a database. The consistency means, whatever happens in the middle of the transaction, this property will never leave your database in a half-completed state. If the transaction completed successfully, then it will apply all the changes to the database. If there is an error in a transaction, then all the changes that already made will be rolled back automatically. It means the database will restore to its state that it had before the transaction started. If there is a system failure in the middle of the transaction, then also, all the changes made already will automatically rollback.
Isolation
Isolation property ensures that multiple transactions can occur concurrently without leading to the inconsistency of database state. Changes occurring in a particular transaction will not be visible to any other transaction until that particular change in that transaction is written to memory or has been committed.
Durability
Once the transaction completed, then the changes it has made to the database will be permanent. Even if there is a system failure, or any abnormal changes also, this SQL acid property will safeguard the committed data.
Atomicity
The atomicity means either all the operations (insert, update, delete) inside a transaction take place or none. Or you can say, all the statements (insert, update, delete) inside a transaction are either completed or rolled back. There is no midway i.e. transactions do not occur partially. Atomicity is also known as the ‘All or nothing rule’.
Consistency
Consistency refers to the correctness of a database. The consistency means, whatever happens in the middle of the transaction, this property will never leave your database in a half-completed state. If the transaction completed successfully, then it will apply all the changes to the database. If there is an error in a transaction, then all the changes that already made will be rolled back automatically. It means the database will restore to its state that it had before the transaction started. If there is a system failure in the middle of the transaction, then also, all the changes made already will automatically rollback.
Isolation
Isolation property ensures that multiple transactions can occur concurrently without leading to the inconsistency of database state. Changes occurring in a particular transaction will not be visible to any other transaction until that particular change in that transaction is written to memory or has been committed.
Durability
Once the transaction completed, then the changes it has made to the database will be permanent. Even if there is a system failure, or any abnormal changes also, this SQL acid property will safeguard the committed data.
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