How Can I Efficiently Find the Row Position in MySQL After Ordering?

Efficiently obtain row positions after MySQL sorting

In a MySQL table, determining the position of a specific row after sorting based on a specific column (e.g. 'name') requires an optimized approach to avoid loading a large result set.

Consider the following query:

<code class="language-sql">SELECT x.id,
       x.position,
       x.name
  FROM (SELECT t.id,
               t.name,
               @rownum := @rownum + 1 AS position
          FROM TABLE t
          JOIN (SELECT @rownum := 0) r
      ORDER BY t.name) x
 WHERE x.name = 'Beta'</code>

This query uses a subquery to assign row positions based on the ORDER BY clause and then filters the required row 'Beta'. The position is calculated using the @rownum user variable, which is automatically incremented for each row.

Alternatively, you can use the following query to handle the tie differently:

<code class="language-sql">SELECT t.id,
       (SELECT COUNT(*)
          FROM TABLE x
         WHERE x.name < t.name) + 1 AS position
  FROM TABLE t
 WHERE t.name = 'Beta'</code>

This method returns the same position for parallel rows and may provide a different result set than the first query.

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