중간고사에 레거시 파일시스템의 문제점 5가지가 나올 거시다~

Advantages of the Database Approach

• Program - data independence

  • data descriptions are stored in a central location called the "repository"

• Planned data redundancy

• Improved data consistency

• Improved data sharing

  • a "user view" is a logical description of some portion of th e database that is required by a user to perform some task.
  • a user view is often developed by identifying a form or report that the user needs on a regular basis.

• Increased productivity of application development

  • without having to worry about file design or low-level implementation details.
  • Provides a number of high-level productivity tools : forms and report generatorl and high-level language (SQL)

• Enforcement of standards

  • Name conventions : data quality standards, and uniform procedures for accessing, updating, and protecting data.

• Improved data quailty

  • Constraint (called also "business rule") : "relational integrity constraint". 데이터 무결성을 보장해주기 위한 제한.

    = DBMS / built - in tool이 많아서 짜잘한거 짤 필요가 없다~

• Improved data accessibility and responsiveness

  • Structured Query Language (SQL)

• Reduced program maintenance

  • Y2K problem

• Improved decision support

DB 특 : 두단어로 하면 공유 & 통합. Integration & Sharedness.

Costs and Risks of DB approach

• New, specialized personnel 전문가가 필요함.

• Installation and managment cost and complexity 비용 비싸

• Conversion costs

• Need for explicit backup and recovery / 데이터 웨어하우스

• Organizational conflict

SDLC Systems Development Life Cycle

그림이 있따~
Enterprise →

PPT 올려주시겠다~
빅데이터 특 5V를 잘 알아둬라~ 퀴즈에 나올수가있다~

Data Lake => 하둡의 기반기술