Getting Started 01

Enging=innodb

InnoDb is one of MySQL's database engines, and the biggest envoy is the acid-compatible thing (Transaction) feature, similar to Postersql

ACID: An abbreviation for four basic elements that the database thing is correctly executed

A atomicity: atomicity: Beauty: [?? T?m '? S?ti]

The whole process of your execution is either complete or complete. If an error occurs during execution, it is rolled back to the state it was in before the thing started, and no action was taken on the data.

C Conformance: Consistency

is protection and invariance. The overall status of the data can not be changed, for example, I have 100 yuan, you have 100 yuan, add up the total is 200 yuan, can not say I transferred to you 50, two of the total account has become 150 yuan.

I isolation: Isolation

Only one request processes the same data at the same time.

D Persistence: Durability

After the whole thing is done, changes made to the database are persisted in the database and will not be rolled back.

============== There are two ways to achieve acid: the first is write ahead logging that is, the way the logs are (modern databases are based on this approach) the central idea of Wal is that modifications to the data file must be done after the log records are flushed to the permanent storage.

The second type is SHADW paging.

Getting Started 01