How to Count Unique Values in an Access Query?

Calculating Unique Entries in Access Queries

Standard Access Count(*) functions can't directly handle unique value counts. To accurately count distinct entries within a specific field, a modified query is required.

The following query demonstrates how to obtain a distinct count of the "Name" field from the "table1" table:

<code class="language-sql">SELECT Count(*) AS N
FROM
(SELECT DISTINCT Name FROM table1) AS T;</code>

This approach leverages a subquery to initially extract unique "Name" values. The outer query then counts the rows from this subquery's result set, yielding the correct unique count.

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