title: test ssis transformation expressions in management studio and creating an expression
body: <p>I am trying to remove part of a string from another string, for example:</p>
  
  <pre><code>declare @url varchar (20)
  set @url = 'www.test.com~~34235645463544563554'
  
  select @url, substring(@url,1,CHARINDEX('~~',@url)-1)
  </code></pre>
  
  <p>I am trying to remove '~~34235645463544563554'</p>
  
  <p>I am use to using the built in tsql functions (as shown above) to do this but trying to do the same thing in a step in ssis as a "derived column transformation". Can someone suggest how I can do this and whether there is a easy way to quickly test this out in management studio? ie using the expression written in ssis to test for the expected result. I would prefer not to run the whole thing as it is a big package.</p>