How can I have multiple common table expressions in a single SELECT statement?

Question

I am in the process of simplifying a complicated select statement, so thought I would use common table expressions.

Declaring a single cte works fine.

WI         


        

Answer 1

I think it should be something like:

WITH 
    cte1 as (SELECT * from cdr.Location),
    cte2 as (SELECT * from cdr.Location)
select * from cte1 union select * from cte2

Basically, WITH is just a clause here, and like the other clauses that take lists, "," is the appropriate delimiter.

Answer 2

Above mentioned answer is right:

WITH 
    cte1 as (SELECT * from cdr.Location),
    cte2 as (SELECT * from cdr.Location)
select * from cte1 union select * from cte2

Aditionally, You can also query from cte1 in cte2 :

WITH 
    cte1 as (SELECT * from cdr.Location),
    cte2 as (SELECT * from cte1 where val1 = val2)

select * from cte1 union select * from cte2

val1,val2 are just asumptions for expressions..

Hope this blog will also help : http://iamfixed.blogspot.de/2017/11/common-table-expression-in-sql-with.html