Imply bit with constant 1 or 0 in SQL Server

Question

cast (
  case
    when FC.CourseId is not null then 1 else 0
  end
as bit)

The CAST spec is "CAST (expression AS type)". The CASE is an expression in this context.

If you have multiple such expressions, I'd declare bit vars @true and @false and use them. Or use UDFs if you really wanted...

DECLARE @True bit, @False bit;
SELECT @True = 1, @False = 0;  --can be combined with declare in SQL 2008

SELECT
    case when FC.CourseId is not null then @True ELSE @False END AS ...

You might add the second snippet as a field definition for ICourseBased in a view.

DECLARE VIEW MyView
AS
  SELECT
  case 
  when FC.CourseId is not null then cast(1 as bit)
  else cast(0 as bit)
  end
  as IsCoursedBased
  ...

SELECT ICourseBased FROM MyView

No, but you could cast the whole expression rather than the sub-components of that expression. Actually, that probably makes it less readable in this case.

Slightly more condensed than gbn's:

Assuming CourseId is non-zero

CAST (COALESCE(FC.CourseId, 0) AS Bit)

COALESCE is like an ISNULL(), but returns the first non-Null.

A Non-Zero CourseId will get type-cast to a 1, while a null CourseId will cause COALESCE to return the next value, 0

If you want the column is BIT and NOT NULL, you should put ISNULL before the CAST.

ISNULL(
   CAST (
      CASE
         WHEN FC.CourseId IS NOT NULL THEN 1 ELSE 0
      END
    AS BIT)
,0) AS IsCoursedBased

The expression to use inside SELECT could be

CAST(IIF(FC.CourseId IS NOT NULL, 1, 0) AS BIT)