Explain ACID rule of thumb for transactions.

A transaction must be:
1.� � � � � � Atomic – it is one unit of work and does not dependent on previous and following transactions.
2.� � � � � � Consistent – data is either committed or roll back, no “in-between” case where something has been updated and something hasn’t.
3.� � � � � � Isolated – no transaction sees the intermediate results of the current transaction).
4.� � � � � � Durable – the values persist if the data had been committed even if the system crashes right after.