declare @firstTable nvarchar(10);
select top(1) @firstTable=c01 from (select top(2) c01 from C order by c01 asc) as c1;
declare @secondTable nvarchar(10);
select top(1) @secondTable=c01 from (select top(2) * from C order by c01 desc)as c2;

exec('select top(2) a01 as t01,a02 as t02 from '+ @firstTable+' union '+' select top(2) * from '+@secondTable);

------解决方案--------------------
SQL code

if object_id('A') is not null
    drop table A;
go

if object_id('B') is not null
    drop table B;
go

if object_id('C') is not null
    drop table C;

if object_id('temp') is not null
    drop table temp;
go

--创建测试表
create table A
(
    a01 int,
    a02 int
);
go

create table B
(
    b01 int,
    b02 int
);
go

create table C
(
    c01 nvarchar(10),
    c02 nvarchar(10)
);
go

--插入测试数据
insert into A
select 1, 11 union all
select 2, 22;
go

insert into B
select 10, 101 union all
select 20, 201;
go

insert into C
select 'A', 'xx' union all
select 'B', 'xx';
go

--生成动态查询语句
declare @sql nvarchar(max);
set @sql = '';

declare @table_name nvarchar(10);
declare @i int;
set @i = 0;

declare cur_c cursor for
    select c01 from C;

open cur_c;
fetch next from cur_c into @table_name;

while @@fetch_status = 0
begin
    if @i = 0
        set @sql = @sql + 'select * into temp from ' + @table_name;
    else
        set @sql = @sql + ' union all select * from ' + @table_name;
    set @i = @i + 1;
    fetch next from cur_c into @table_name;
end;

close cur_c;
deallocate cur_c;

--执行动态查询语句
exec (@sql);
go

--检查结果
select *
from temp;
go
/*
a01         a02
----------- -----------
1           11
2           22
10          101
20          201
*/