Tuesday, December 15, 2020

SQL Logical Query Processing Order

Order of SQL Query processing

1. FROM (Choose and join tables to get base data)
- table to query
- join
2. WHERE (Filters the base data)
- filter rows
- only rows for which predicates is true
3. GROUP BY (Aggregates the base data)
- it associates each input rows to its respective group
4. HAVING (Filters the base data)
- filters the aggregated data.
5. SELECT(Window functions happen here!)
- returns the final data
6. ORDER BY
-Sorts the final data
7. OFFSET FETCH (LIMIT,Paging)
- Limits the returned data toa row count

2 comments:

  1. Full Stack developer course in Hyderabad
    The article offers useful and easy-to-understand tips. It presents the information in a clear and engaging way. It’s a great resource for those who want to gain knowledge quickly.

    ReplyDelete
  2. The Full Stack Developer Course in Hyderabad
    by Brolly Academy is designed to help learners master both front-end and back-end web development skills. This course covers technologies like HTML, CSS, JavaScript, React, Node.js, Express, and MongoDB, enabling students to build complete, dynamic web applications from scratch. With hands-on projects, real-time coding experience, and expert mentorship, Brolly Academy ensures that learners gain practical knowledge and job-ready skills to become professional full stack developers in today’s competitive IT industry.
    Full stack developer course in hyderabad

    ReplyDelete

SOLID-Design-Principles

SOLID-Design-Principles The SOLID principles are fundamental to designing effective, maintainable, object-oriented systems. Whether you...