title: Sphinx match by first letter
body: <p>I need simple explanation of why my queries fail to bring the results i need.</p>
  
  <p>Sphinx 2.0.8-id64-release (r3831)
  Here is what i have in sphinx.conf:</p>
  
  <pre><code>SELECT
  trackid,
  title,
  artistname,
  SUBSTRING(REPLACE(TRIM(`artist_name`), 'the ', ''),1,3) AS artistname_init
  ....
  
  sql_field_string = title
  sql_field_string = artistname
  sql_field_string = artistname_init
  </code></pre>
  
  <p>Additional settings:</p>
  
  <pre><code>docinfo = extern
  charset_type = utf-8
  min_prefix_len = 1
  enable_star = 1
  expand_keywords= 0
  charset_table = U+FF10..U+FF19-&gt;0..9, 0..9, U+FF41..U+FF5A-&gt;a..z,  U+FF21..U+FF3A-&gt;a..z, A..Z-&gt;a..z, a..z
  </code></pre>
  
  <p>Query works. I index my data without problems. However i am failing to make sphinx bring any sensible results. I am using SphinxQL to query.</p>
  
  <p>Example:</p>
  
  <pre><code>select
  artistname, artistname_init from myindex
  WHERE MATCH('@artistname_init ^t*')
  GROUP BY artistname ORDER BY artistname_init ASC limit 0,10;
  </code></pre>
  
  <p>brings nothing related to the query.
  I've tried everything i could think of like:</p>
  
  <pre><code>MATCH('@artistname_init ^t*')
  MATCH('@artistname_init[1] t')
  MATCH('@artistname_init ^t$')
  </code></pre>
  
  <p>Can anyone please point where is my mistake and perhaps give me query that will work for my case?
  My target is to get results that follow this sorting order:</p>
  
  <pre><code>B (Single letter)
  B-T (Single letter + non-alphabet sign after)
  B as Blue (Single letter + space after)
  Baccara (First letter of single word)
  Bad Religion (First letter of several words)
  The B (not counting "The ")
  The B.Y.Z (Single letter + non-alphabet sign after not counting "The ")
  The B 2 B (Single letter + space after not counting "The ")
  The Boyzz (First letter of single word not counting "The ")
  The Blue Boy (First letter of several words not counting "The ")
  </code></pre>
  
  <p>Or close to it.</p>