Advanced SQL Part 2

Views: Named Queries

Subqueries in FROM

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Advanced SQL

Run the query with an empty S:

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Database Intro & Basic SQL

Intro

  • A database is a large, organized collection of data.
  • A Database Management System (DBMS) is software that stores, manages and facilitates access to databases.
    • 传统DBMS即关系型数据库管理系统 Relational Database Management Systems (RDBMS)
    • SQL 数据描述和操作语言
    • ACID 数据库事务(Transaction)正确执行的四个基本要素的缩写:原子性(Atomicity)、一致性(Consistency)、隔离性(Isolation)、持久性(Durability)
  • Various levels of a database system

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