Thank you !

Where must I specify the length more then 1 symbol ?

I use nvarchar(20) everywhere, but it doesn't help (

In the morning I dont have right variant.

Now I have 4 right variants:

SELECT TOP 1 WITH TIES LastName, COUNT (*) AS CountOfBooks FROM

(SELECT LastName FROM Libs L, S_Cards S

WHERE S.id_lib...

Both variants are right for my task )

I like more my variant and your first variant.

Your second variant i dont like )

I wanna specify: the second your variant is faster than first ?

I have 2 right variants: big and small.

Small variant:

SELECT TOP 1 WITH TIES LastName, COUNT (*) AS [count] FROM

(SELECT LastName FROM Libs L, S_Cards S

WHERE S.id_lib = L.id

UNION ALL

SELECT LastName...

A resolved yet !