Question

In a Fabric warehouse, an analyst maintains a DimCustomer table and receives a daily StagingCustomer table containing all customers from the source system. The analyst needs a query that returns only the customers in StagingCustomer that do NOT already exist in DimCustomer (matched on CustomerKey), so that only genuinely new customers are identified for insertion. Which T-SQL approach returns exactly this set?

Accepted Answer

SELECT s.* FROM StagingCustomer s LEFT JOIN DimCustomer d ON s.CustomerKey = d.CustomerKey WHERE d.CustomerKey IS NULL

Answer

SELECT s.* FROM StagingCustomer s INNER JOIN DimCustomer d ON s.CustomerKey = d.CustomerKey

Answer

SELECT s.* FROM StagingCustomer s FULL OUTER JOIN DimCustomer d ON s.CustomerKey = d.CustomerKey

Answer

SELECT s.* FROM StagingCustomer s LEFT JOIN DimCustomer d ON s.CustomerKey = d.CustomerKey WHERE d.CustomerKey IS NOT NULL