es – mapping – parameters – null_value

There is no such thing as perfect programming, but we shouldn’t be discouraged because programming is a constant pursuit of perfection.

Q: What are the features of null_value?

A:



Q: How do I use null_value?

A:

# null_value
PUT /null_value_test
{
  "mappings" : {
    "properties" : {
      "name" : {
        "type"       : "keyword"."null_value" : "NULL"
      }
    }
  }
}

# 索引
POST /null_value_test/_doc/1
{
  "name" : null} GET /null_value_test/_search {"query" : {
    "term" : {
      "name" : {
        "value" : "NULL"}}}} # result {"took" : 895."timed_out" : false."_shards" : {
    "total" : 1."successful" : 1."skipped" : 0."failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 1."relation" : "eq"
    },
    "max_score" : 0.2876821."hits": [{"_index" : "null_value_test"."_type" : "_doc"."_id" : "1"."_score" : 0.2876821."_source" : {
          "name" : null}}]}}Copy the code