SQL AND, OR, NOT
邏輯條件組合
使用 AND、OR、NOT 把多個條件組合起來。這些邏輯運算子是寫出商業規則查詢的核心。
Example 1 - AND
SELECT CustomerName, City FROM Customers WHERE Country = 'Germany' AND City = 'Berlin';
Example 2 - OR
SELECT CustomerName, Country FROM Customers WHERE Country = 'Germany' OR Country = 'France';
Example 3 - NOT
SELECT CustomerName, Country FROM Customers WHERE NOT Country = 'France';
Example 4 - 括號控制優先順序
SELECT CustomerName, Country, City FROM Customers WHERE (Country = 'Germany' OR Country = 'France') AND City IS NOT NULL;
Example 5 - 與日期條件混合
SELECT OrderID, CustomerID, OrderDate FROM Orders WHERE CustomerID = 1 AND NOT OrderDate < '2024-01-01';