Home Database Mysql Tutorial How Can I Correctly Count Approved Comments in MySQL to Avoid a Minimum of 1?

How Can I Correctly Count Approved Comments in MySQL to Avoid a Minimum of 1?

Nov 28, 2024 am 03:48 AM

How Can I Correctly Count Approved Comments in MySQL to Avoid a Minimum of 1?

Solving Comment Count Issue with IF Condition in MySQL Query

You're facing an issue where your MySQL query consistently returns a minimum comment count of 1 even in the absence of approved comments for certain news articles. To rectify this, let's explore a revised approach.

Your query employs the count() function to tally approved comments, but it inherently yields a minimum value of 1 for every row, irrespective of comment existence. The solution lies in utilizing the sum() function instead.

Consider the following modified query:

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SELECT

    ccc_news . * ,

    SUM(if(ccc_news_comments.id = 'approved', 1, 0)) AS comments

FROM

    ccc_news

    LEFT JOIN

        ccc_news_comments

    ON

        ccc_news_comments.news_id = ccc_news.news_id

WHERE

    `ccc_news`.`category` = 'news_layer2'

    AND `ccc_news`.`status` = 'Active'

GROUP BY

    ccc_news.news_id

ORDER BY

    ccc_news.set_order ASC

LIMIT 20

Copy after login

In this revised version, we utilize the sum() function within the if() statement's conditional expression. It calculates the aggregate count of 1's for approved comments and 0's for unapproved comments, effectively returning an accurate tally of approved comments for each news article.

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