DAX Studio with SUMMARIZE.... error 'Not a table expression"

[ilcaa722]

i am in DAX studio and i have this code... if i remove the last evaluate to just show tbl, it returns a table...BUT when i try to use this table in an COUNTROWS() function, it fails "the query specific is not a table expression) ...  why??  (please dont worry about countrows, its actually  adifferent calc, but testing with COUTNROWS() fails as well)

define    
var tbl=
    SUMMARIZE(Sales, Products[ProductKey], Sales[ProductStandardCost])
evaluate
    tbl
evaluate
    COUNTROWS(tbl)

[FreemanZ · Accepted solution]

hi @ilcaa722 

try like:

define    
var tbl=
    SUMMARIZE(Sales, Products[ProductKey], Sales[ProductStandardCost])
evaluate
    tbl
evaluate
    {COUNTROWS(tbl)}

COUNTROWS returns a value, while a table is expected here