Select Only One Row from Second Table Using MySQL INNER JOIN

When using MySQL INNER JOIN to combine two tables, it is common to want to select only one row from the second table. This can be achieved by using the LIMIT clause in combination with the INNER JOIN.

Assuming we have two tables named "table1" and "table2" with a common column named "id", and we want to select only one row from "table2" for each row in "table1" based on the highest "date" column:

<?php
    $sql = "SELECT t1.*, t2.*
            FROM table1 t1
            INNER JOIN (
                SELECT id, MAX(date) AS max_date
                FROM table2
                GROUP BY id
                ) t2
            ON t1.id = t2.id
            AND t2.max_date = table2.date
            LIMIT 1";
?>

In the above example, we are using a subquery to select the maximum "date" value for each "id" in "table2". We then join this subquery with "table1" using the common "id" column, and also include a condition to match the maximum "date" value with the corresponding row in "table2". Finally, we use the LIMIT clause with a value of 1 to select only one row from "table2".

By using this method, we can easily select only one row from the second table when using MySQL INNER JOIN.

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