Utilizing COUNT(*) Effectively in MySQL WHERE Clauses
To achieve the desired result in MySQL, where you aim to select distinct gid values with a COUNT(*) condition exceeding 10 and sort the results in descending order, the approach you suggested using a nested SELECT query within the WHERE clause may not be the most efficient.
Instead, consider employing the GROUP BY and HAVING clauses to accompalish your task. Here's the corrected query:
Understanding the Query
The GROUP BY clause organizes the gd table data by the gid column. This action aggregates rows with the same gid value.
Following that, the HAVING clause applies a filter to the grouped rows, selecting only those with a COUNT(*) greater than 10. This ensures that the returned results meet your specified frequency criteria.
Finally, the ORDER BY clause arranges the remaining rows in descending order based on the lastupdated timestamp, giving you the desired sorting.
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