Home > Database > Mysql Tutorial > body text

Here are a few title options, based on the provided snippet: Option 1 (Focus on the Problem): * How to Calculate Topic Review Counts using Multi-Table Left Joins in SQL? Option 2 (Focus on the Tech

Susan Sarandon
Release: 2024-10-26 10:58:29
Original
729 people have browsed it

Here are a few title options, based on the provided snippet:

Option 1 (Focus on the Problem):

* How to Calculate Topic Review Counts using Multi-Table Left Joins in SQL?

Option 2 (Focus on the Technique):

* Using Left Joins to Count Topic Reviews: A S

Joining Tables to Calculate Counts for Topic Review

To derive a "Topic_Review" table with the desired counts, a multi-table left join operation is required.

The query below employs a series of left joins to combine the data from three tables: "Messages," "Topics," and "Stars_Given." The "left join" condition ensures that all rows from "Topics" are included in the result, even if they have no corresponding entries in the other tables.

<code class="sql">select
  t.Topic,</code>
Copy after login

The above is the detailed content of Here are a few title options, based on the provided snippet: Option 1 (Focus on the Problem): * How to Calculate Topic Review Counts using Multi-Table Left Joins in SQL? Option 2 (Focus on the Tech. For more information, please follow other related articles on the PHP Chinese website!

source:php.cn
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Latest Articles by Author
Popular Tutorials
More>
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template
About us Disclaimer Sitemap
php.cn:Public welfare online PHP training,Help PHP learners grow quickly!