Union two selects removing duplicates base on some columns (not the full row)

try

select * from table1
union
select * from table2
where not exists(select 1 from table1 
                 where table2.parent = table1.parent 
                 and table2.type = table1.type)

try this:

;WITH cte AS (
   SELECT *, 1 AS SetID FROM table1 WHERE [Type] = 1
   UNION ALL
   SELECT *, 2 AS SetID FROM table2 
)

,cte2 as (
   SELECT *,
   RANK() OVER (PARTITION BY [Type], [Parent] ORDER BY SetID) FROM cte) rk
   FROM cte
)

SELECT * FROM cte2 WHERE rk = 1

Tags:

Sql

Sql Server

Related