How to Retrieve the Top 3 Recent Records per User Group in Access SQL?

Efficiently Retrieving the Three Most Recent Records per User Group in Access SQL

Database management often involves retrieving specific subsets of data. In scenarios like tracking test scores, you might need to extract the three most recent entries for each individual user. This task, while seemingly simple, requires a sophisticated SQL query to combine the selection of recent records with the grouping of data by user.

The following SQL query provides a solution:

<code class="language-sql">SELECT PR1.LogInID, PR1.Score, PR1.[Date Taken]
FROM Progress AS PR1
WHERE PR1.[Date Taken] IN (
                        SELECT TOP 3 PR2.[Date Taken]
                        FROM Progress PR2
                        WHERE PR2.LoginID = PR1.LoginID
                        ORDER BY PR2.[Date Taken] DESC
                        )
ORDER BY LoginID, [Date Taken] DESC;</code>

Query Breakdown:

This query utilizes a subquery (inner query) within the main query (outer query) to achieve the desired result.

• Subquery: This nested query identifies the three most recent "Date Taken" values for each unique LoginID. It does this by:

  • Selecting the top three [Date Taken] values.
  • Filtering the Progress table (PR2) to only include records matching the LoginID from the outer query (PR1.LoginID).
  • Ordering the results in descending order by [Date Taken] to ensure the most recent dates are prioritized.

• Main Query: The main query then filters the Progress table (PR1) using the IN operator. This operator ensures that only records whose [Date Taken] value is present in the result set of the subquery (i.e., the three most recent dates for that user) are included. Finally, the results are ordered by LoginID and then by [Date Taken] (descending) for easy readability.

This approach efficiently retrieves the three most recent scores for each user, handling potential ties in the [Date Taken] field effectively. The combined use of subqueries and the IN operator provides a concise and powerful solution to this common database challenge.

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