Locking a temp table in a stored procedure

The answer is to not use a temp table at all. This query can be written AND run much more efficiently by using what is referred to as a virtual table. It looks something like this:

BEFORE:

Select col1, sum(col2) testsum
Into #temp
>From table1
Group by col1

Select col1, col4, sum(testsum) secondaryagg
>From table2 inner join #temp on table2.col1 = #temp.col1
Group by col1, col4

Select col1, col4, sum(testsum) secondaryagg
>From table2 inner join 
 (Select col1, sum(col2) testsum
  From table1
  Group by col1) a on table2.col1 = a.col1
Group by col1, col4

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