title: String manipulation in SQL Server-- adding placeholder characters
body: <p>I'm a little green when it comes to SQL Server string manipulation functions.  If I have a string with six characters in it, say:</p>
  
  <pre><code>DECLARE @p_MyStringVariable VARCHAR (100) 
  SET @p_MyStringVariable = 'FANFFF'
  </code></pre>
  
  <p>And I want to insert, say, the letter 'M' in the first and seventh positions of the final string and assign that to another VARCHAR variable to read 'MFANFFMF', how can I best do that?  And am I correct in reading that SQL Server strings are indexed starting from one, instead of zero?  I'm thinking of the SUBSTRING() function, for instance.</p>
  
  <p>(Note that some strings will be up to 100 characters in length, thus the VARCHAR(100) declaration above, even for a six-character string)</p>
  
  <p>Thanks much for your help.</p>