title: stored procedure with wildcard parameters
body: <p>I've a table </p>
  
  <pre><code>create table user (userId varchar(8) not null, userName varchar(8) not null)
     insert into user
       select 'NAME1','name1'
       union all
       select 'NAME2', 'name2'
       union all
       select 'NAME3','name3'
  </code></pre>
  
  <p>I've used stored procedure for wild card parameters as:</p>
  
  <pre><code>create procedure wildcard_name
  @userName nchar(8)=  '%'
  as
  select * from user
  where userName like @userName;
  
  exec wildcard_name 'n%';
  </code></pre>
  
  <p>the exec statement is not giving any result,why?</p>