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  • Elasticsearch:Elasticsearch SQL介绍及实例

    SQL 实操

    检索Elasticsearch schema 信息:DSL vs SQL

    首先,我们确定表/索引的schema以及可供我们使用的字段。 我们将通过REST界面执行此操作:

    POST /_sql
    {
      "query":"desc sports"
    }

    上面的命令结果:

    {
      "columns" : [
        {
          "name" : "column",
          "type" : "keyword"
        },
        {
          "name" : "type",
          "type" : "keyword"
        },
        {
          "name" : "mapping",
          "type" : "keyword"
        }
      ],
      "rows" : [
        [
          "age",
          "INTEGER",
          "integer"
        ],
        [
          "birthdate",
          "TIMESTAMP",
          "datetime"
        ],
        [
          "goals",
          "INTEGER",
          "integer"
        ],
        [
          "location",
          "GEOMETRY",
          "geo_point"
        ],
        [
          "name",
          "VARCHAR",
          "keyword"
        ],
        [
          "rating",
          "INTEGER",
          "integer"
        ],
        [
          "role",
          "VARCHAR",
          "keyword"
        ],
        [
          "score_weight",
          "REAL",
          "float"
        ],
        [
          "sport",
          "VARCHAR",
          "keyword"
        ]
      ]
    }

    也可以通过url参数format = txt以表格形式格式化以上响应。 例如:

    POST /_sql?format=txt 
    {
      "query": "DESCRIB sports"
    }

    上面查询结果

    |   column     |     type      |    mapping    
    ---------------+---------------+---------------
    age            |INTEGER        |integer        
    birthdate      |TIMESTAMP      |datetime       
    goals          |INTEGER        |integer        
    location       |GEOMETRY       |geo_point      
    name           |VARCHAR        |keyword        
    rating         |INTEGER        |integer        
    role           |VARCHAR        |keyword        
    score_weight   |REAL           |float          
    sport          |VARCHAR        |keyword        

    也可以通过控制台实现相同的查询,需要使用一下命令登陆:

    cd /home/elastic/elasticsearch-7.5.1
    ./bin/elasticsearch-sql-cli http://192.168.1.234:9200

    可以看到SQL的命令提示符了,可以直接输入sql

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  • 原文地址:https://www.cnblogs.com/fat-girl-spring/p/12895166.html
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