Evolution of DBMS：

Punched-Card Record
1914 - 1918 WWI
1929 - 1933 Big Depression ( Bank )
1939 - 1945 WWII
1950 magnetic tape
1955 Programmed Record Managers ( Batch Processing )
- Con：Transaction error 無法即時被偵測 - didn't know the current situation.
1965 - 1980 On-line Network Database
- Indexed sequential records 建立索引
- Data independence 資料獨立性 * Physical * Logical
- Concurrent Access 一致性
- Con：Programming interface are too low level.
1970 E.F. Codd Outline the Relational Model
1976 Peter Chen E-R Model

ACID：

Atomicity：
- happen or none happen 全有全無
- IDEA : keep a log ( history ) for all actions
Consistency
Isolation：每一筆 transaction 都是獨立的
Durability：耐久性