declare @name sysname
DECLARE @sqlfilter VARCHAR(max)
declare csr cursor
for select TABLE_NAME from INFORMATION_SCHEMA.TABLES where TABLE_NAME like 'box_mac_%'
open csr
FETCH NEXT FROM csr INTO @name
while (@@FETCH_STATUS=0)
BEGIN
set @sqlfilter='alter table '+@name+' add drive_quite_start datetime null'
print @sqlfilter;
exec(@sqlfilter);
fetch next from csr into @name
END
CLOSE csr
DEALLOCATE csr