sql - how can i calculate between 2 date count of solution time in MSSQL

Question

SELECT* from ticketOperations  
--this is operations table
INNER JOIN tickets ON tickets.ID = ticketOperations.ticketID, 
--they connect with foreign key
DATEDIFF(DAY,tickets.date, ticketOperations.closingDate) AS SOLUTIONTIME  
--this is calculatefunction 
WHERE tickets.ticketType=0 
--tickettype

Answer 1

You are facing issue as you are using DATEDIFF in ON clause without any expression or condition.

Msg 208, Level 16, State 1, Line 6 Invalid object name 'DATEDIFF'. that's my error string

If you want to know the difference in date then use it in the SELECT clause.

SELECT tickets.*, ticketOperations.*,
       DATEDIFF(DAY,tickets.date, ticketOperations.closingDate) AS SOLUTIONTIME  
  from ticketOperations  
 INNER JOIN tickets ON tickets.ID = ticketOperations.ticketID, 
 WHERE tickets.ticketType=0