TRIM is not a recognized built-in function name

Question

TRIM is introduced in SQL Server (starting with 2017).

In older version of SQL Server to perform trim you have to use LTRIM and RTRIM like following.

DECLARE @ss varchar(60)
  SET @ss=" admin "

  select RTRIM(LTRIM(@ss))

If you don’t like using LTRIM, RTRIM everywhere, you can create your own custom function like following.

   CREATE FUNCTION dbo.TRIM(@string NVARCHAR(max))
    RETURNS NVARCHAR(max)
     BEGIN
      RETURN LTRIM(RTRIM(@string))
     END
    GO