Examples of of how to create of delete a temp table in SQL Server, depending on the temp table's existence.
--
-- To create a temp table (#Users) if it doesn't already exist:
if OBJECT_ID('tempdb..#Users') is null
begin
create table #Users(
id int not null,
username varchar(50) not null
);
end;
go
--
-- To delete a temp table (#Users) if it exists:
if OBJECT_ID('tempdb..#Users') is not null
begin
drop table #Users;
end;
go