Elasticsearch 简明教程
Elasticsearch - Mapping
映射是存储在索引中的文档的概要。它定义了数据类型（如 geo_point 或 string）和文档中存在的字段的格式，以及控制动态添加的字段的映射的规则。
Mapping is the outline of the documents stored in an index. It defines the data type like geo_point or string and format of the fields present in the documents and rules to control the mapping of dynamically added fields.
PUT bankaccountdetails
{
"mappings":{
"properties":{
"name": { "type":"text"}, "date":{ "type":"date"},
"balance":{ "type":"double"}, "liability":{ "type":"double"}
}
}
}当我们运行上述代码时，会得到如下所示的响应：
When we run the above code, we get the response as shown below −
{
"acknowledged" : true,
"shards_acknowledged" : true,
"index" : "bankaccountdetails"
}Field Data Types
Elasticsearch 支持为文档中的字段设置不同类型的数据类型。此处详细讨论了用于在 Elasticsearch 中存储字段的数据类型。
Elasticsearch supports a number of different datatypes for the fields in a document. The data types used to store fields in Elasticsearch are discussed in detail here.
Core Data Types
这些数据类型为 text、keyword、date、long、double、boolean 或 ip 等基本数据类型，几乎所有系统都支持。
These are the basic data types such as text, keyword, date, long, double, boolean or ip, which are supported by almost all the systems.
Complex Data Types
这些数据类型组合了核心数据类型。其中包括数组、JSON 对象和嵌套数据类型。嵌套数据类型的示例如下所示：
These data types are a combination of core data types. These include array, JSON object and nested data type. An example of nested data type is shown below &minus
POST /tabletennis/_doc/1
{
"group" : "players",
"user" : [
{
"first" : "dave", "last" : "jones"
},
{
"first" : "kevin", "last" : "morris"
}
]
}当我们运行上述代码时，会得到如下所示的响应：
When we run the above code, we get the response as shown below −
{
"_index" : "tabletennis",
"_type" : "_doc",
"_id" : "1",
_version" : 2,
"result" : "updated",
"_shards" : {
"total" : 2,
"successful" : 1,
"failed" : 0
},
"_seq_no" : 1,
"_primary_term" : 1
}另一个示例代码如下所示：
Another sample code is shown below −
POST /accountdetails/_doc/1
{
"from_acc":"7056443341", "to_acc":"7032460534",
"date":"11/1/2016", "amount":10000
}当我们运行上述代码时，会得到如下所示的响应：
When we run the above code, we get the response as shown below −
{ "_index" : "accountdetails",
"_type" : "_doc",
"_id" : "1",
"_version" : 1,
"result" : "created",
"_shards" : {
"total" : 2,
"successful" : 1,
"failed" : 0
},
"_seq_no" : 1,
"_primary_term" : 1
}我们可以使用以下命令检查上述文档：
We can check the above document by using the following command −
GET /accountdetails/_mappings?include_type_name=falseRemoval of Mapping Types
在 Elasticsearch 7.0.0 或更高版本中创建的索引不再接受 default 映射。在 Elasticsearch 6.x 中创建的索引将继续在 Elasticsearch 6.x 中像以前一样运行。Elasticsearch 7.0 中不再提供 API 类型的支持。
Indices created in Elasticsearch 7.0.0 or later no longer accept a default mapping. Indices created in 6.x will continue to function as before in Elasticsearch 6.x. Types are deprecated in APIs in 7.0.