How to prevent not in results from appending to union clause

Asked Dec 16 '20 at 21:55

Active Dec 16 '20 at 21:55

Viewed 43 times

I am trying to union two result sets and omit the results from the first set when returning the second unioned set.

However, when the second set is selected it is appending the data from the sub-query.

declare @bool nvarchar(1) = 'Y'

select [name[
from table_1
where @bool = 'N'

union

select [name]
from table_2 t2
where @bool = 'Y'
and [name] not in (
  select [name]
  from table_1
)

How can I select the second part when @bool = 'Y' without the not in sub-query appending its results to the dataset?

asked Dec 16 '20 at 21:55

Matthew

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2

As you have written the query, the results should come from one of the subqueries, but not both. – Gordon Linoff Dec 16 '20 at 21:56
1

you query is already doing what you want – eshirvana Dec 16 '20 at 22:03
@RyanWilson It's a switch to simplify the API when pulling in data from disparate sources. – Matthew Dec 16 '20 at 22:09
@eshirvana I see that now. I had a longer chained query that was missing part of a where-clause statement. – Matthew Dec 16 '20 at 22:10

How to prevent not in results from appending to union clause

0 Answers0