Need BOOLEAN Result from SQL EXISTS Statement without using a WHERE Clause

exists, sql-server, t-sql

Solution

Here is one which uses `EXISTS` with `CASE WHEN ... THEN .. ELSE ... END`, tested with MySQL and Oracle:

SELECT 
  CASE WHEN EXISTS 
    (SELECT  cx.id
     FROM fdd.admissions_view as cx  
     WHERE cx.id=1111 and cx.campus='MEXI')
  THEN 1 
  ELSE 0 
  END 
FROM DUAL

Update:

Found some related Q/A:

- Optimizing SELECT COUNT to EXISTS

- is it possible to select EXISTS directly as a bit?

Problem

Is there any way in a simple query to return a Boolean value using an SQL EXISTS statement without using a WHERE clause? All of the 2008 R2 SQL Server Books Online examples show another WHERE clause and two tables. Website examples show either a WHERE or an IF-THEN-ELSE in a procedure. I was hoping to do the following on one table: ``` EXISTS (SELECT cx.id FROM fdd.admissions_view as cx WHERE cx.id=1111 and cx.campus='MEXI') ``` The SELECT statement works fine and returns the ID. I just want to add EXISTS to return a BOOLEAN, but the syntax above is not valid. Can I do something like this? If so, what am I missing syntax-wise? If not, what other technique may work? Please advise. Thanks.

Original source

Related problems