SQL-Server-Tutorial/SQL Server Left Join.sql at main · krasigarev/SQL-Server-Tutorial · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
SELECT
    product_name,
    order_id
FROM production.products p
LEFT JOIN sales.order_items o ON o.product_id = p.product_id
ORDER BY order_id;
GO

SELECT
    [product_name],
    [order_id]
FROM production.products AS p
LEFT JOIN sales.order_items AS o ON o.product_id = p.product_id
WHERE [order_id] IS NULL;
GO

SELECT
    p.product_name,
    o.order_id,
    i.item_id,
    o.order_date
FROM production.products p
LEFT JOIN sales.order_items i  ON i.product_id = p.product_id
LEFT JOIN sales.orders o ON o.order_id = i.order_id
ORDER BY order_id;
GO

SELECT
    product_name,
    order_id
FROM production.products p
LEFT JOIN sales.order_items o ON o.product_id = p.product_id
WHERE order_id = 100
ORDER BY order_id;
GO

SELECT
    p.product_id,
    product_name,
    order_id
FROM production.products p
LEFT JOIN sales.order_items o  ON O.product_id = p.product_id AND o.order_id = 100
ORDER BY order_id DESC;
GO