Question

I have two sql tables, one with id and name and other with id. I want to get as result – table with 3 columns, first id, second name, third true/false if id is in both tables or not. for example :

Table 1       Table 2   result ->   Table 3
1   Mike      2                     1 Mike false 
2   John      4                     2 John true
3   Roger                           3 Roger false
4   Richard                         4 Richard true

this is what I wan`t to accomplish. Do you have any suggestions

Answer 1

Left join will return row even if a match is not found. This row will consist of null values.

select t1.id, 
       t1.name,
       case when t2.id is null 
            then 'False' 
            else 'True' 
        end DoesExist
  from Table1 t1
  left join Table2 t2
    on t1.ID = t2.ID