Data from Derived Table

I am looking to run two different queries.

the first one returns about 6000 numbers. i.e 123454, 15432, 2343545 etc

My second query i want to use the results from the first query as a where clause?

i.e

where Number in ('123454','15432','2343545')

Clearly i dont want to type out 6000 numbers in a query. How do i use the data generated in the first query as the where criterea in the second query.

You can use the following query...(subquery)

Select Numbers From SomeTable -- Which returns 6000 numbers

on your second query..

..

..

Where Number in(Select Numbers From Sometable)