数据库原理-CS3322

CS SE方向选修

Lec1

课程要求

• 作业5-6次，不计分
• 大作业1个（4-5个部分），40%
• 期末综合练习，60%

Describing Data

• Data Model

  • a collection of concepts for describing data.

• Schema

  • a description of a particular collection of data, using a given data model.

• Relational model of data

  • the most widely used model today
  • Main concept: relation, basically a table with rows and columns.
  • Every relation has a schema, which describes the columns, or fields.

Concurrency Control

• key to good DBMS performance ->
• ensures such problems don’t arise.
  • Users/programmers can pretend they are using a single-user system. (called “Isolation”)

Database Management Systems (DBMS)

• DBMS used to maintain, query large datasets.

  • can manipulate data and exploit semantics

• Other benefits include

  • recovery from system crashes,
  • concurrent access,
  • quick application development,
  • data integrity and security.

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