title: Import into Elasticsearch from repeatedly created JSON but store old values
body: <p>New to Elasticsearch and Kibana so please bear with me. I'm not using Logstash but JSON files to import the information I need. Basically, Kibana is used for monitoring change in values in MySQL database over time. Right now, transfer of information works by a script to 1)delete previous versions of JSON files containing my information, 2)export MySQL information into JSON format files, and 3)Re-importing the newly created JSON files. </p>
  
  <p>Each row of my data has a timestamp. Here comes the problem. The old versions of the information I imported are no longer reflected in Kibana (maybe cause the previous files I deleted?). Is there a way to keep the information with the old timestamps and simultaneously import the new ones?</p>