====== 2.2 Queries with Linked Tables ======

SQL queries on Gateway data in Access.

===== Simple Query =====

<code sql>
SELECT * FROM Customers
WHERE Country = 'Germany'
ORDER BY Name;
</code>

===== Join =====

<code sql>
SELECT c.Name, o.OrderDate, o.Total
FROM Customers AS c
INNER JOIN Orders AS o ON c.Id = o.CustomerId
WHERE o.OrderDate > #2024-01-01#;
</code>

===== Performance Tip =====

Filters are forwarded to the server - large amounts of data are not loaded locally.

===== Aggregations =====

<code sql>
SELECT Country, COUNT(*) AS Count
FROM Customers
GROUP BY Country;
</code>