고객별 결제 금액: 고객별 결제 금액을 계산하는 쿼리.

고객별 결제 금액 계산은 고객의 구매 행태, 충성도, 구매력 등을 이해하는 데 중요한 지표입니다. 기업은 이 정보를 활용하여 맞춤형 마케팅, 가격 전략, 고객 서비스 개선 등 다양한 비즈니스 의사결정을 내립니다. 다음은 고객별 결제 금액을 계산하는 SQL 쿼리 예제와 각 예제의 간단한 설명입니다.

예제 1: 고객별 총 결제 금액
SELECT CustomerID, SUM(TotalAmount) AS TotalPaid FROM Orders GROUP BY CustomerID;
각 고객별로 모든 주문에 대한 총 결제 금액을 계산합니다.

예제 2: 고객별 최근 결제 금액
SELECT CustomerID, TotalAmount FROM Orders WHERE OrderDate IN (SELECT MAX(OrderDate) FROM Orders GROUP BY CustomerID);
각 고객별로 가장 최근 주문의 결제 금액을 조회합니다.

예제 3: 특정 기간 동안 고객별 결제 금액
SELECT CustomerID, SUM(TotalAmount) AS TotalPaid FROM Orders WHERE OrderDate BETWEEN '2023-01-01' AND '2023-12-31' GROUP BY CustomerID;
2023년 동안 각 고객별로 결제한 총 금액을 계산합니다.

예제 4: 고객별 평균 결제 금액
SELECT CustomerID, AVG(TotalAmount) AS AveragePaid FROM Orders GROUP BY CustomerID;
각 고객별로 평균 결제 금액을 계산합니다.

예제 5: 고객별 최대 결제 금액
SELECT CustomerID, MAX(TotalAmount) AS MaxPaid FROM Orders GROUP BY CustomerID;
각 고객별로 지불한 최대 금액을 조회합니다.

예제 6: 특정 고객의 결제 이력
SELECT OrderDate, TotalAmount FROM Orders WHERE CustomerID = 'C123';
'C123' 고객의 모든 결제 이력(날짜와 금액)을 조회합니다.

예제 7: 특정 카테고리 상품을 구매한 고객별 결제 금액
SELECT CustomerID, SUM(TotalAmount) AS TotalPaid FROM Orders JOIN OrderDetails ON Orders.OrderID = OrderDetails.OrderID WHERE ProductID IN (SELECT ProductID FROM Products WHERE Category = 'Electronics') GROUP BY CustomerID;
'Electronics' 카테고리 상품을 구매한 각 고객별로 결제 금액을 계산합니다.

예제 8: 고객별 연도별 결제 금액
SELECT CustomerID, YEAR(OrderDate) AS Year, SUM(TotalAmount) AS TotalPaid FROM Orders GROUP BY CustomerID, YEAR(OrderDate);
각 고객별로 연도별 결제 금액을 계산합니다.

예제 9: 할인 받은 주문의 고객별 결제 금액
SELECT CustomerID, SUM(TotalAmount) AS TotalPaid FROM Orders WHERE Discount > 0 GROUP BY CustomerID;
할인을 받은 주문에 대한 각 고객별 결제 금액을 계산합니다.

예제 10: 고객별 가장 오래된 결제 금액
SELECT CustomerID, TotalAmount FROM Orders WHERE OrderDate IN (SELECT MIN(OrderDate) FROM Orders GROUP BY CustomerID);
각 고객별로 가장 오래된 주문의 결제 금액을 조회합니다.

관련 전문용어 설명
고객 ID(CustomerID): 고객을 식별하는 고유한 번호 또는 문자열입니다.
총액(Total Amount): 주문에 대한 총 금액입니다.
평균(Average): 특정 데이터 집합의 평균값을 의미합니다.
할인(Discount): 상품이나 서비스의 정가에서 줄어든 비율이나 금액을 의미합니다.