ACID of the transaction
Atomicity: Either all succeed or all fail.
Consistency: Two SQL statements for data consistency.
Permanence: SQL takes effect permanently.
Isolation:
Transaction isolation level:
The first level
can only be written by one
The second level
one write, read and write is prohibited
Level 3 When
a transaction is read n times, read and write are prohibited
The fourth level of
serialization,
each transaction is queued for execution,
Solve in turn
1. Lost update
2. Dirty read (read not submitted)
3. Non-repeatable read
4. Phantom read
Three paradigms:
First normal form: indivisible
Second normal form:
Third Normal Form:
