title: How to store image eigenvalue in mysql?
body: <p>I work in image match these days, I need to store image color eigenvalue in the mysql for query image match. I use java to do that.</p>
  
  <p>The eigenvalue should store in structure like key-value(HSV color - Number of that color), such like:</p>
  
  <p><code>"257094":0.067,"257350":0.063,"258374":0.055,"256070":0.039,"257606":0.038,"258886":0.037...</code></p>
  
  <p><a href="https://i.stack.imgur.com/td2jy.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/td2jy.png" alt="enter image description here"></a></p>
  
  <p>I use Map store it, transform it to <code>json</code> string and store it in the mysql for field type <code>longtext</code>. So when a query comes, I pick up the json string from database and transform it to map then compare.</p>
  
  <p>But My method's performance is too low, is it that any better method can deal with it? </p>