checkout_id is the primary key. Each row represents one tool checkout made by a technician.
The equipment center identifies frequent borrowers as technicians who made at least three checkouts.
Find the number of frequent technicians. Count every checkout row regardless of tool category or checkout duration. Return one row with the result in a column named frequent_technician_count. Return 0 when no technician qualifies or when the table is empty.
Output
+---------------------------+---------+
| Column Name | Type |
+---------------------------+---------+
| frequent_technician_count | integer |
+---------------------------+---------+
+---------------------------+---------+
| Column Name | Type |
+---------------------------+---------+
| frequent_technician_count | integer |
+---------------------------+---------+
Explanation: Technician 1 makes two checkouts and does not reach the threshold. Technician 2 makes exactly three checkouts and qualifies, so the result is 1.
