Elasticsearch dynamic mapping - automatic detection

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ES has a very important feature - dynamic mapping , which does not need to create an index, type and other information prior to index documents, while the index will automatically index, type, create maps.

So what is mapping it? Mapping is to describe the type of the field, how to analyze, how to make content indexing.

It focuses on the Benpian, ES in the automatic detection of mapping characteristics.

More Reference: Elastisearch knowledge summary

Automatic detection field

When a field for the first time, if not previously been defined mapping, ES will automatically detect the type it possible to meet, and then create a corresponding map.

JSON data	ES Data Type
`null`	Will not add fields
`true` or `false`	boolean
floating point number	double
integer	long
object	object
array	The first relies on a non-null Found
string	If by the date test, compared with date If by the numeric test, compared with Number

The above result is the type of automatic detection, in addition to the basic types listed above, other types such as advanced geo, ip need to manually specify.

Date Automatic detection

Date automatically detect that date_detection is enabled by default, so that they meet the default date format, it can automatically create the type to date

Date format is:

[ "strict_date_optional_time","yyyy/MM/dd HH:mm:ss Z||yyyy/MM/dd Z"]

E.g:

$ curl -XPUT localhost:9200/test/test/1 -d '{"create":"2015/11/11"}'
{"_index":"test","_type":"test","_id":"1","_version":1,"created":true}

$ curl -XGET localhost:9200/test/_mapping?pretty
{
  "test" : {
    "mappings" : {
      "test" : {
        "properties" : {
          "create" : {
            "type" : "date",
            "format" : "yyyy/MM/dd HH:mm:ss||yyyy/MM/dd"
          }
        }
      }
    }
  }
}

By modifying dynamic_date_formats change the date format:

PUT my_index
{
    "mappings":{
        “my_type":{"dynamic_date_formats":["MM/dd/yyyy"]}
    }
}

PUT my_index/my_type/1{"create_date":"09/25/2015"}

Digital automatic detection

Digital automatic detection, i.e. numeric_detection is off by default. Hence the need to manually open:

PUT my_index
{"mappings":{"my_type":{"numeric_detection":true}}}

When performing index operations, if they meet a float, it will automatically create a float

long type is the same:

Reproduced in: https: //my.oschina.net/u/204616/blog/545150