How to execute the GO statement with dynamic count? - sql

Question

How to set dynamic count for GO statement?
I am getting the following error:
A fatal scripting error occurred.Incorrect syntax was encountered
while parsing Go.
when I tried to run the below query:
Declare #count int
Select #count=COUNT(*) From Users
Insert Into #DummyUsers
Select * from Users where UserName = 'Sachin'
GO #Count
But the same is working fine when I use the below query with hard coded count.
Declare #count int
Select #count=COUNT(*) From Users
Insert Into #DummyUsers
Select * from Users where UserName = 'Sachin'
GO 5
Appreciate your suggestions if you have any idea on this.

Answer 1

You can't. As soon as SSMS encounters GO the batch is terminated and your variable no longer exists.

Answer 2

You can't use a variable for the count parameter to GO, but in your example (which may be contrived) you could just join back to Users :
Insert Into #DummyUsers
Select U.* from Users U
INNER JOIN Users U2
ON U.UserName = 'Sachin'
Other options:
Dynaimc SQL (building up SQL by concatenating strings) and executing via SQLCMD.EXE or OSQL.EXE
Using a WHILE loop with a counter

Answer 3

If you simply want to insert a repeated row you could use a CTE or numbers table.
-- Sample data.
declare #Users as Table ( UserId Int Identity, Name VarChar(16) );
insert into #Users ( Name ) values
( 'Bob' ), ( 'Carol' ), ( 'Ted' ), ( 'Alice' );
select * from #Users;
-- Load another table with repetitions of a single user.
declare #TempUsers as Table ( UserId Int, Name VarChar(16) );
declare #Repetitions as Int = ( select Count(*) from #Users );
with TempUsers as (
select UserId, Name, 1 as Repetitions
from #Users
where Name = 'Ted'
union all
select UserId, Name, Repetitions + 1
from TempUsers
where Repetitions < #Repetitions
)
insert into #TempUsers ( UserId, Name )
select UserId, Name
from TempUsers;
select * from #TempUsers;

Answer 4

Instead try this.
DECLARE #cntr INT=1
WHILE #cntr <= #count
BEGIN
INSERT INTO #DummyUsers
SELECT *
FROM Users
WHERE UserName = 'Sachin'
SET #cntr+=1
END

Answer 5

I would just loop it
Declare #count int
Select #count=COUNT(*) From Users
WHILE(#count > 0)
BEGIN
Insert Into #DummyUsers
Select *
FROM Users
WHERE UserName = 'Sachin'
SET #count = #count - 1;
END

Answer 6

While I agree with the others that there is likely a better way to achieve what you are trying to do, if there is some limitation that we are not seeing, you could look into using a sequence
The sequence you create persists and can be reset as needed and you can "increment" it by calling the NEXT VALUE FOR function