sql server - left join not showing null values -

I have to search for the objects present in Table A, but not in Table B. Now join this way in MySQL will be really simple

  Select * Add a left to B. Key = BK Where b. Although for some reason it is not working in MSSQL, I have created the query to see all the results without looking, and I only see matches, not zero values Sees Do not you know why this is not working?  
 I know that I can optionally use "when not present" but I want to know why the reason is not working with joining.  
 I'm adding code for your review  
  Absences.CustomerID, b. Choose (choose * from Openquire) (JUNACAACEEE, 'Select from PlanetGuosters cmp_wwn where i_outcome = 4')) Dissemination of absence on Asbmissis. Customer ID = B Cmp_wwn where Absences.Type = 3223    
 
 
 your  where  Segment is filtering zero values:  
  where absences.Type = 3223   
 you enter  openquery  in the subquery Goes to the left  Absences ; And then only filter the rows containing a specific (non-zero) value in the   column.  
 Do you mean that  Absences  to  openquery ?