ACID stands for
- Atomicity
- Consistency
- Isolation
- Durablity
Atomicity
Modification on the data in the database either fail or succeed. The beginning of such a modification starts with a transaction and ends when a transaction finishes (either by a commit or a rollback). A software crash entails an implicit rollback.
Consistency
Only valid data (valid according to integrity constraints) may be committed.
Isolation
One transaction does not interfere with another. The ‘executor’ of a transaction has the feeling that he has the entire database for himself.
Durability
A committed transaction will not be lost.
Source: http://en.wikipedia.org/wiki/ACID
The explanation given was slightly wrong from the actual- here are the true meaning as per:
• Atomicity ‐ A transaction either happens completely, or none of it happens.
• Consistency ‐ A transaction takes the database from one consistent state to the next.
• Isolation ‐ The effects of a transaction may not be visible to other transactions until
the transaction has committed.
• Durability ‐ Once the transaction is committed, it is permanent.