SQL 기본 문법

SQL Select

1. SELECT * FROM Customers;
2. SELECT City FROM Customers;
3. SELECT DISTINCT Country FROM Customers;

SQL Where

1. SELECT * FROM Customers
   WHERE City = 'Berlin';
2. SELECT * FROM Customers
   WHERE NOT CIty = 'Berlin';
3. SELECT * FROM Customers
   WHERE CustomerID = 32;
4. SELECT * FROM Customers
   WHERE City = 'Berlin'
   AND PostalCode = 12209;
5. SELECT * FROM Customers
   WHERE City = 'Berlin'
   OR City = 'London';

SQL Order By

1. SELECT * FROM Customers
   ORDER BY City;
2. SELECT * FROM Customers
   ORDER BY City DESC;
3. SELECT * FROM Customers
   ORDER BY Country, City;

SQL Insert

1. INSERT INTO Customers (
   CustomerName,
   Address,
   City,
   PostalCode,
   Country )
   VALUES (
   'Hekkan Burger',
   'Gateveien 15',
   'Sandnes',
   '4306',
   'Norway');

SQL Null

1. SELECT * FROM Customers
   WHERE PostalCode IS NULL;
2. SELECT * FROM Customers
   WHERE PostalCode IS NOT NULL;

SQL Update

1. UPDATE Customers
   SET City = 'Oslo';
2. UPDATE Customers
   SET City = 'Oslo'
   WHERE Country = 'Norway';
3. UPDATE Customers
   SET City = 'Oslo',
   Country = 'Norway'
   WHERE CustomerID = 32;

SQL Delete

1. DELETE FROM Customers
   WHERE Country = 'Norway';
2. DELETE FROM Customers;

SQL Functions

1. SELECT MIN(Price)
   FROM Products;
2. SELECT MAX(Price)
   FROM Products;
3. SELECT COUNT(*)
   FROM Products
   WHERE Price = 18;
4. SELECT AVG(Price)
   FROM Products;
5. SELECT SUM(Price)
   FROM Products;

SELECT Like

1. SELECT * FROM Customers
   WHERE City LIKE 'a%';
2. SELECT * FROM Customers
   WHERE City LIKE '%a';
3. SELECT * FROM Customers
   WHERE City LIKE '%a%';
4. SELECT * FROM Customers
   WHERE City LIKE 'a%b';
5. SELECT * FROM Customers
   WHERE City NOT LIKE 'a%';

SQL Wildcards

1. SELECT * FROM Customers
   WHERE City LIKE '_a%';
2. SELECT * FROM Customers
   WHERE City LIKE '[acs]%';
3. SELECT * FROM Customers
   WHERE City LIKE '[a-f]%';
4. SELECT * FROM Customers
   WHERE City LIKE '[!acf]%';

SQL In

1. SELECT * FROM Customers
   WHERE Country IN ('Norway','France');
2. SELECT * FROM Customers
   WHERE Country NOT IN ('Norway', 'France');

SQL BETWEEN

1. SELECT * FROM Products
   WHERE Price BETWEEN 10 AND 20;
2. SELECT * FROM Products
   WHERE Price NOT BETWEEN 10 AND 20;
3. SELECT * FROM Products
   WHERE ProductName BETWEEN 'Geitost' AND 'Pavlova';

SQL Alias

1. SELECT CustomerName,
   Address,
   PostalCode AS Pno
   FROM Customers;
2. SELECT *
   FROM Customers AS Consumers;

SQL JOIN

1. SELECT *
   FROM Orders
   LEFT JOIN Customers
   ON Orders.CustomerID = Customers.CustomerID;
2. SELECT *
   FROM Orders
   INNER JOIN Customers
   ON Orders.CustomerID=Customers.CustomerID;
3. SELECT *
   FROM Orders
   RIGHT JOIN Customers
   ON Orders.CustomerID=Customers.CustomerID;

SQL Group By

1. SELECT COUNT (CustomerID),
   Country
   FROM Customers
   GROUP BY Country;
2. SELECT COUNT (CustomerID),
   Country
   FROM Customers
   GROUP BY Country
   ORDER BY COUNT(CustomerID) DESC;

SQL Database

6. ALTER TABLE Persons
   ADD Birthday DATE;
7. ALTER TABLE Persons
   DROP COLUMN Birthday;