两个存储过程有什么不同吗？一个有结果一个没有啊？

[dragoner]

CREATE PROCEDURE epd_item_master_search_sp( @item_codes char(25))
AS
SELECT @item_codes= RTRIM(@item_codes) + '%'
select item_code,item_name,item_model,item_spec from epd_item_master where item_code like @item_codes
order by item_code ASC;


exec epd_item_master_search_sp 'GB';




CREATE procedure epd_item_master_search_sp
AS
select item_code,item_name,item_model,item_spec from epd_item_master where item_code like 'GB%'
order by item_code ASC;

exec epd_item_master_search_sp;
前面一个没有啊，后面一个有结果啊，这是为什么，存储过程有错误吗？

[txlicenhe]

CREATE PROCEDURE epd_item_master_search_sp( @item_codes char(25))
AS
SELECT @item_codes= RTRIM(@item_codes) + '%'
select item_code,item_name,item_model,item_spec from epd_item_master where item_code like ''''+@item_codes +'%'
order by item_code ASC;


exec epd_item_master_search_sp 'GB';

[伍子V5]

CREATE PROCEDURE epd_item_master_search_sp( @item_codes char(25))
AS
SELECT @item_codes= RTRIM(@item_codes) + '%'
exec('select item_code,item_name,item_model,item_spec from epd_item_master where item_code like '''+@item_codes+'''')
order by item_code ASC;

[zjcxc]

--数据类型的问题,第一个改用下面的就行了.
CREATE PROCEDURE epd_item_master_search_sp( @item_codes varchar(25))
AS
SELECT @item_codes= RTRIM(@item_codes) + '%'
select item_code,item_name,item_model,item_spec
from epd_item_master where item_code like @item_codes
order by item_code ASC;

[伍子V5]

CREATE PROCEDURE epd_item_master_search_sp( @item_codes char(25))
AS
SELECT @item_codes= RTRIM(@item_codes) + '%'
exec('select item_code,item_name,item_model,item_spec from epd_item_master where item_code like '''+@item_codes+''' order by item_code ASC')