SQL Server 2008 Performance Tuning (T-SQL) Multiple LEFT JOIN Table vs. View

Question

I have 20+ supporting tables created as follows.

[common_column1, common_column2, unique_column]

I need to create a combo table or view that will be customized this way

[common_column1, common_column2, 
 table1_unique_column, table2_unique_column, table3_unique_column, etc...]

I have 6 million records in each supporting table. My combined query to create a table / view is as follows:

select 
   a.common_column1, a.common_column2, a.unique_column, b.unique_column, 
   c.unique_column, d....  
into combined_table  
from table1 as a   
left join table2 as b on (a.common_column1 = b.common_column1 and a.common_column2 = b.common_column2)  
left join table3 as c on (a.common_column1 = c.common_column1 and a.common_column2 = c.common_column2)  
left join table4 as d ...`   

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Answer 1

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Answer 2

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Answer 3

:

CREATE INDEX ix_b_1_2_unique ON b (common_column1, common_column2) INCLUDE (unique_column)

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2 (common_column1, common_column2) , 1048576 a.

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