Question

I get the error: Msg 2714, Level 16, State 1, Line 16
There is already an object named ‘#mytemptable’ in the database.

There are ways around it, but wonder why this happens. Seems like SQL Server is verifying both blocks of the if/else statement?

declare @choice int
select @choice = 1

if @choice = 1
    begin
        select 'MyValue = 1' AS Pick into #my_temp_table
    end
else
    begin
        select 'MyValue <> 1' AS Pick into #my_temp_table
    end

select * from #my_temp_table

drop table #my_temp_table

If the tables have different names, it works. Or if I create the temp table and use Insert Into… statements that works as well.

Answer 1

See here: What is deferred name resolution and why do you need to care?

basically you need to ceate the table first

So what is happening is that beginning with SQL server 7 deferred name resolution was enabled for real tables but not for temporary tables. If you change the code to use a real table instead of a temporary table you won’t have any problem

Here is another way

 declare @choice int
    select @choice = 1

declare @Value varchar(100)
 if @choice = 1
 select @Value = 'MyValue = 1'
 else
 select @Value = 'MyValue <> 1'

    select @Value AS Pick into #my_temp_table
    select * from #my_temp_table

    drop table #my_temp_table