The concept of business and its four characteristics
Techniques for creating redundant data in database recovery mechanisms (data dumps and logging log files)
Three types of data inconsistency caused by concurrent operations
Blocking is an important technology to achieve concurrency control, the concept of blocking and two types of blocking.
Definition of Serializable Scheduling
Two-stage lock protocol
practice questions
1. Fill in the blanks
Writing a modification to the database is two different operations from writing a running record representing the modification to the log file. The order of these two operations should be ( B ) . A. Do the former first B. Do the latter first C. Programmers make arrangements in the program D. Which one to do first is determined by the system
The constraint of "age between 15 and 30 years old" belongs to the ( C ) function of the DBMS. A. Recovery B. Concurrency Control C. Integrity D. Security
When the first transaction reads data A in S-locked mode, the second transaction will fail to read data A ( A ). A. Read with X lock B. Read with S lock C. Read without lock D. Read with shared lock