in 与exists？该怎么解决

in 与exists？？？？
select article ,dealer,price 
from shop  
where article=0001 
or dealer IN (select dealer from shop where article=0001);

装换成exists？？怎么结果不对，谁能帮弄下。
select article ,dealer,price 
from shop  
where 
article=0001 
or
 exists (select dealer from shop where 
shop.dealer=shop.dealer and
 article=0001 );


[解决办法]

SQL code

SELECT article ,dealer,price  FROM shop   WHERE   article=0001  orEXISTS(SELECT dealer FROM shop WHERE  article=0001 );