Using IIF in SQL update statement

Question

My existing SQL statement

  UPDATE EMP 
  SET fte_adj = IIf((fte<1 Or fte Is Null) And [employment category] Like '*Full-Time*',1,
IIf((fte=0 Or fte Is Null) And [employment category] Like '*Part-Time*',0.25,fte));

it will update table EMP

set fte_adj=1
if Full time (and fte<1 or null)

set fte_adj=0.25
if part time (and fte=0 or null)

otherwise fte_adj=fte

How can I add a case to check is there any records for the employee_id exists in another table SEC_EMP ?

if there is no records (0 row), then set fte_adj=1

both table can use employee_id as key

thanks

Solution 1

I've rewritten your statement using CASE (but I realize IIF works in 2012):

UPDATE EMP 
SET fte_adj = 
  CASE WHEN (FTE < 1 OR FTE IS NULL) AND [employment category] Like '*Full-Time*'
    THEN 1
  ELSE
    CASE WHEN (FTE = 0 OR FTE IS NULL) AND [employment category] Like '*Part-Time*'
      THEN 0.25
    ELSE 
      CASE WHEN (SELECT COUNT(*) FROM SEC_EMP) = 0 
      THEN 1
      ELSE 
        FTE
      END
    END
  END

And here is some sample Fiddle.

If you prefer the IIF logic, here you go:

UPDATE EMP 
SET fte_adj = 
  IIF ( (FTE < 1 OR FTE IS NULL) AND [employment category] Like '*Full-Time*' , 1 ,
      IIF ( (FTE = 0 OR FTE IS NULL) AND [employment category] Like '*Part-Time*' , 0.25, 
          IIF ( (SELECT COUNT(*) FROM SEC_EMP) = 0 , 1 , FTE ) 
          )
       )

And more Fiddle.

--EDIT--

If I'm understanding latest comment, you want to update records that ONLY exist in the SEC_EMP table? If so, just JOIN to the table as such:

UPDATE E 
SET fte_adj = 
  IIF ( (FTE < 1 OR FTE IS NULL) AND [employment category] Like '*Full-Time*' , 1 ,
      IIF ( (FTE = 0 OR FTE IS NULL) AND [employment category] Like '*Part-Time*' , 0.25, FTE 
          )
       )
FROM EMP E
  JOIN SEC_EMP SE ON E.employee_id = SE.employee_id 

And more Fiddle.

Solution 2

Try this:

UPDATE EMP 
SET fte_adj = CASE WHEN fte=1 Or fte Is Not Null And [employment category] Like '%Full-Time%'
THEN 1 ELSE .25 END AS 'Rate'

I'd also add

 WHERE [employment category] Like '%Full-Time%' OR [employment category] Like '%Part-Time%'

For safety depending on your table. This is for MS SQL btw, no idea what '* syntax *' is from.

Comments

[Mark Kram]

Have you thought of using a Case statement instead?

[Lamak]

His current sql query is most likely for ms-access

[sgeddes]

@Lamak -- I'd guess SQL Server 2012

[Lamak]

@sgeddes that's also an option

[Joe Yan]

Sorry that there is missing in my question. I need to check is there any rows for the employee_id exists in another table "SEC_EMP". is it true that i add a WHERE clause at the end that EMP.employee_id = SEC_EMP.employee_id ?

[sgeddes]

@JoeYan -- so you only want to update records that exist in SEC_Emp -- easy enough if that's the case -- let me know and I'll update the answer using a JOIN.

[sgeddes]

@JoeYan -- I've updated my answer -- that will update only users that match in the SEC_EMP table. Hope this helps (and that I understood your requirements correctly).

[Joe Yan]

thanks sgeddes. it is true that i want to update records that ONLY exist in the SEC_EMP table.

[sgeddes]

@JoeYan -- no problem -- glad I could help!

[Joe Yan]

For using CASE statement, I put the JOIN table statement after the CASE END. UPDATE EMP SET fte_adj = CASE WHEN XXX END FROM EMP A INNER JOIN SEC_EMP B ON A.EMPLOYEE_ID=B.EMPLOYEE_ID