How to Retrieve Only the First Row in a LEFT JOIN Query?

How to Retrieve Only the First Row in a LEFT JOIN Query

Database operations involve efficiently retrieving and manipulating data, and understanding database structures and relationships is crucial. In this example, the focus is on extracting only the first record from a LEFT JOIN operation, which can pose challenges.

The LEFT JOIN operation allows you to merge data from two tables by comparing their common columns. When you encounter multiple matches in the right table, it returns all of them. However, in some scenarios, you may only be interested in the first record.

One way to approach this is to use a subquery within the LEFT JOIN. In this case, a subquery is employed to retrieve the artist_id of the first entry in the feeds_artists table for a specific feed_id. This subquery is then utilized in the LEFT JOIN to retrieve the corresponding artist information.

<code class="sql">SELECT *
FROM feeds f
LEFT JOIN artists a ON a.artist_id = (
    SELECT artist_id
    FROM feeds_artists fa 
    WHERE fa.feed_id = f.id
    LIMIT 1
)
WHERE f.id = '13815'</code>

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