Ciro Santilli  Sponsor 中国独裁统治 China Dictatorship 新疆改造中心、六四事件、法轮功、郝海东、709大抓捕、2015巴拿马文件 邓家贵、低端人口、西藏骚乱
Each transaction isolation level specifies what can or cannot happen when two queries are being run in parallel, i.e.: the memory semantics of the system.
Remember that queries can affects thousands of rows, and database systems like PostgreSQL can run multiple such queries at the same time.
Good summary on the PostgreSQL page:
Implementation specifics:



  1. SQL transaction
  2. SQL feature
  3. SQL
  4. Relational database management system
  5. Relational database
  6. Database
  7. Software
  8. Computer
  9. Information technology
  10. Area of technology
  11. Technology
  12. Ciro Santilli's Homepage