Why is my SQL query counting all rows instead of individual rows, and how can I fix it using GROUP BY?

Troubleshooting SQL Queries: Incorrect Row Counts and the GROUP BY Solution

Your SQL query is producing an inaccurate row count, summing all rows instead of individual ones. The solution lies in employing the GROUP BY clause within the subquery that joins with the messages_aura table. GROUP BY aggregates rows with identical values in the specified columns, providing the correct counts.

Problem and Solution:

The original LEFT JOIN to messages_aura lacked a GROUP BY clause:

LEFT JOIN
(
    SELECT `ID` AS `AuraID`, `Status` AS `AuraStatus`, COUNT(*) AS `Aura`
    FROM messages_aura
) aura ON (var.Poster = aura.AuraID AND var.ID = aura.AuraStatus)

This resulted in an incorrect Aura count because it totaled all rows in messages_aura. Adding GROUP BY fixes this:

LEFT JOIN
(
    SELECT `ID` AS `AuraID`, `Status` AS `AuraStatus`, COUNT(*) AS `Aura`
    FROM messages_aura
    GROUP BY AuraID, AuraStatus
) aura ON (var.Poster = aura.AuraID AND var.ID = aura.AuraStatus)

Now, each row in messages_aura is uniquely identified by AuraID and AuraStatus, leading to accurate Aura counts. The COUNT(*) function correctly aggregates for each unique combination of AuraID and AuraStatus.

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