Code Monkey home page Code Monkey logo

Comments (2)

digoal avatar digoal commented on May 24, 2024 1

内部没有本质区别吧, 由于索引内没有版本信息, 无法直接通过索引判断可见性.
需要回表或者通过vm减少回表.
如果都是btree, unique index和normal index, 没啥效率上的区别.

from blog.

isdaniel avatar isdaniel commented on May 24, 2024

是的 經過我的測試和查找相關文章 unique Index 在某些情境能幫助 QO 建立較優執行計畫，在 postgres 中並沒有像在 sql-server 那樣會有 many to many 優化的事情
感謝德哥回答 我先把 issue 關閉了

from blog.

Related Issues (20)

Recommend Projects

  • React photo React

    A declarative, efficient, and flexible JavaScript library for building user interfaces.

  • Vue.js photo Vue.js

    🖖 Vue.js is a progressive, incrementally-adoptable JavaScript framework for building UI on the web.

  • Typescript photo Typescript

    TypeScript is a superset of JavaScript that compiles to clean JavaScript output.

  • TensorFlow photo TensorFlow

    An Open Source Machine Learning Framework for Everyone

  • Django photo Django

    The Web framework for perfectionists with deadlines.

  • D3 photo D3

    Bring data to life with SVG, Canvas and HTML. 📊📈🎉

Recommend Topics

  • javascript

    JavaScript (JS) is a lightweight interpreted programming language with first-class functions.

  • web

    Some thing interesting about web. New door for the world.

  • server

    A server is a program made to process requests and deliver data to clients.

  • Machine learning

    Machine learning is a way of modeling and interpreting data that allows a piece of software to respond intelligently.

  • Game

    Some thing interesting about game, make everyone happy.

Recommend Org

  • Facebook photo Facebook

    We are working to build community through open source technology. NB: members must have two-factor auth.

  • Microsoft photo Microsoft

    Open source projects and samples from Microsoft.

  • Google photo Google

    Google ❤️ Open Source for everyone.

  • D3 photo D3

    Data-Driven Documents codes.