How to Accurately Count Unique Values in an Access Query?

Efficiently Counting Unique Records in Access Queries

Standard COUNT(DISTINCT field) syntax may fail when counting unique values within Access queries. Here's a reliable workaround:

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

This approach uses a subquery to first isolate distinct Name values from table1. The outer query then counts the number of rows in this resulting subset, accurately reflecting the unique count.

Illustrative Example:

Let's use this table1:

ID	Name	Family
1	A	AA
2	B	BB
3	A	AB
4	D	DD
5	E	EE
6	A	AC

Applying the query:

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

Result:

<code>+-------------+
| UniqueCount |
+-------------+
| 4           |
+-------------+</code>

This clearly shows the correct count of unique names (A, B, D, E). This method provides a robust and accurate solution for counting unique values in your Access database.

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