How to Retrieve the First Artist Name in a LEFT JOIN Query?

Resolving "LEFT JOIN Only First Row" Query Issues

In this query, you aim to retrieve the first Artist name associated with a specific Feed while performing a LEFT JOIN. However, your original approach using a subquery within the ON clause did not yield the desired results.

To address this issue, we need to adjust the subquery to retrieve the minimum artist_id, ensuring that the earliest Artist is selected. This requires a slight modification to your query:

<code class="sql">SELECT *
FROM feeds f
LEFT JOIN artists a ON a.artist_id = (
    SELECT
      MIN(fa.artist_id) a_id
    FROM feeds_artists fa 
    WHERE fa.feed_id = f.feed_id
)</code>

Explanation:

This updated query employs the MIN() function to determine the minimum artist_id for the corresponding feed_id. Since the artist_id is assumed to increment over time, the minimum value represents the earliest Artist associated with that Feed.

Additional Considerations:

It's important to note that this approach assumes the following:

• The artist_id continuously increments, ensuring the earliest Artist is identifiable.
• There are no duplicate artist_id values for a given feed_id, which could potentially lead to unpredictable results.

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