Question

I am executing the following statement:

;WITH cte AS (
  SELECT 
    1 as rn, 
    'name1' as nm
  UNION ALL
  SELECT 
    rn + 1,
    nm = 'name' + CAST((rn + 1) as varchar(255))
  FROM cte a WHERE rn < 10)
SELECT * 
FROM cte

…which finishes with the error…

Msg 240, Level 16, State 1, Line 2
Types don't match between the anchor and the recursive part in column "nm" of recursive query "cte".

Where am I making the mistake?

Answer 1

Exactly what it says:

'name1' has a different data type to 'name' + CAST((rn+1) as varchar(255))

Try this (untested)

;with cte as
(
select 1 as rn, CAST('name1' as varchar(259)) as nm
union all
select rn+1,nm = 'name' + CAST((rn+1) as varchar(255))
from cte a where rn<10)
select * from cte

Basically, you have to ensure the length matches too. For the recursive bit, you may have to use CAST('name' AS varchar(4)) if it fails again