sql server - How to execute this @query variable? -

sql server - How to execute this @query variable? -

declare @query varchar(200); set @query='select count(*) stud';

i have used this:

exec (@query) execute sp_executesql @query

but it's not working.

error: must declare scalar variable.

how declare scalar variable , how execute query.

use

declare @query nvarchar(max) set @query = 'select count(*) stud' execute sp_executesql @query

sql-server tsql