Acid refers to the four major characteristics of database transactions, the concept proposed by Jim Gray in the late the 1870s, 1983 Andreas Reuter and Theo Härder created acid this abbreviation to describe the four characteristics.
Atomic atomicity means that a transaction is an indivisible whole, either in a completed state or in an unfinished state without an intermediate state.
Conformance consistency refers to the fact that the result of any transaction operation is not allowed to violate data consistency, including the violation of pre-defined constraint constraints.
The isolation isolation is used to control concurrent access to the database, for example, when there are two transactions that read and write to a record in the database, the transaction that reads the operation will have to wait for the write operation to complete. Setting different isolation levels will have different results.
Persistent durability is used to ensure that once a transaction is committed, changes to the data are permanently written to the persistent storage medium (such as a hard disk).
Reference: Http://stackoverflow.com/questions/3740280/acid-and-database-transactions
Https://en.wikipedia.org/wiki/ACID
Four characteristics of the business acid