SQL Server JOIN missing NULL values

Question

Suppose I had the following 2 tables:

      Table1:                                Table2:
Col1:      Col2:     Col3:             Col1:       Col2:       Col         


        

Answer 1

Use Left Outer Join instead of Inner Join to include rows with NULLS.

SELECT Table1.Col1, Table1.Col2, Table1.Col3, Table2.Col4
FROM Table1 LEFT OUTER JOIN 
    Table2 ON Table1.Col1 = Table2.Col1 
    AND Table1.Col2 = Table2.Col2

For more information, see here: http://technet.microsoft.com/en-us/library/ms190409(v=sql.105).aspx