SELECT i.InvoiceID FROM Invoices i LEFT CLEAVE Vendors v ON i.VendorID = v.VendorID

.vscode/settings.json

@@ -30,6 +30,21 @@
             "database": "WideWorldImporters",
             "username": "ben",
             "password": "pass"
+        },
+        {
+            "mssqlOptions": {
+                "appName": "SQLTools",
+                "useUTC": true,
+                "encrypt": true
+            },
+            "previewLimit": 50,
+            "server": "localhost",
+            "port": 1433,
+            "driver": "MSSQL",
+            "name": "server (Examples)",
+            "database": "Examples",
+            "username": "ben",
+            "password": "pass"
         }
     ]
 }

notes/database-prog/sql-scripts/2024-01-31.sql

@@ -32,3 +32,31 @@ FROM Invoices
     JOIN Vendors ON Invoices.VendorID = Vendors.VendorID
 WHERE PaymentDate IS NULL
 ORDER BY InvoiceDueDate
+
+-- Get all vendors with invoices
+-- inter-JOINs only return rows that match on both tables
+SELECT DISTINCT v.VendorID, VendorName FROM Vendors v 
+JOIN Invoices i ON v.VendorID = i.VendorID
+
+-- Outer-JOIN: Returns all of a table plus anything in the other
+-- Get all vendors and invoices if they have any
+SELECT v.VendorID, VendorName, InvoiceID FROM Vendors v
+LEFT JOIN Invoices i ON v.VendorID = i.VendorID
+-- LEFT or RIGHT determines which is the "main one" that the other is joined to
+
+-- CROSS JOIN - combine the tables???
+SELECT v.VendorID, VendorName, InvoiceId
+FROM Vendors v CROSS JOIN Invoices i
+ORDER BY VendorID
+
+-- Get employees and their managers
+SELECT e.EmployeeID, e.LastName, e.FirstName, m.FirstName + ' ' + m.LastName ManagerName
+FROM Employees e JOIN Employees m ON e.ManagerID = m.EmployeeID
+
+-- Customers table has FK Cities, Cities FK State, State FK Countries
+-- To get full address of customers
+SELECT c.CustomerId, c.CustomerName, PostalAddressLine1, ci.CityName, sp.StateProvinceName, cty.CountryName
+FROM Sales.Customers c
+    LEFT JOIN application.Cities ci ON c.DeliveryCityID = ci.CityID
+    JOIN application.StateProvinces sp ON sp.StateProvinceID = ci.StateProvinceID
+    JOIN application.Countries cty ON cty.CountryID = sp.CountryID