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Home >Database >Mysql Tutorial >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

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
Susan SarandonOriginal
2024-10-26 10:58:29916browse

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>

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