anchor.diff:  {"valid":true,"_shards":{"total":1,"successful":1,"failed":0}}
   --------------------------------------------------
   
  -
  -[float]
  -=== Request Parameters
  -
  -When executing exists using the query parameter `q`, the query passed is
  -a query string using Lucene query parser. There are additional
  -parameters that can be passed:
  -
  -[cols="<,<",options="header",]
  -|=======================================================================
  -|Name |Description
  -|`df` |The default field to use when no field prefix is defined within the
  -query.
  -
  -|`analyzer` |The analyzer name to be used when analyzing the query string.
  -
  -|`default_operator` |The default operator to be used, can be `AND` or
  -`OR`. Defaults to `OR`.
  -
  -|`lenient` |If set to true will cause format based failures (like
  -providing text to a numeric field) to be ignored. Defaults to false.
  -
  -|`analyze_wildcard` |Should wildcard and prefix queries be analyzed or
  -not. Defaults to `false`.
  -|=======================================================================
   
   The query may also be sent in the request body:
   
  
positive.code: --------------------------------------------------
  // TEST[skip:the output is randomized depending on which shard we hit]
  
  Response:
  
  [source,console-result]
  --------------------------------------------------
  
negative.code: --------------------------------------------------
  GET twitter/_validate/query?q=user:foo
  --------------------------------------------------
  // TEST[continued]
  
  
  The response contains `valid:true`:
  
  