Question

I can’t use t from

with t as (
        select row_number() OVER (partition by ID ORDER BY id) as numb, * 
        from my_table
        where id= 6
    )

select top 2 from t # it works
select top 2 from t # here I get error Invalid object name 't'.

Is there any tip to use t more than on time?

Answer 1

You cannot do this. CTEs can only be used in one statement (though you can use it multiple times within one statement.

Take a look at this article. Snippit:

Once a CTE is defined, it can be
referenced multiple times by the first
query that follows it.

And from their documentation:

A common table expression (CTE) can be
thought of as a temporary result set
that is defined within the execution
scope of a single SELECT, INSERT,
UPDATE, DELETE, or CREATE VIEW
statement.

Emphasis on, “scope of a single SELECT, INSERT, UPDATE, DELETE, or CREATE VIEW statement.”