ElasticSearch（二）：文档的基本CRUD与批量操作
学习课程链接《Elasticsearch核心技术与实战》
Create 文档
支持自动生成文档_id和指定文档_id两种方式。
- 通过调用
POST index_name/_doc，系统会自动生成文档 _id。
#create document. 自动生成 _id
POST users/_doc
{
"user" : "Mike",
"post_date" : "2019-04-15T14:12:12",
"message" : "trying out Kibana"
}#返回结果
{
"_index" : "users",
"_type" : "_doc",
"_id" : "TyPHr20BkakgvNgYZu2L",#自动生成文档的_id
"_version" : 1,
"result" : "created",
"_shards" : {
"total" : 2,
"successful" : 1,
"failed" : 0
},
"_seq_no" : 1,
"_primary_term" : 1
}- 使用
PUT index_name/_create/_id或PUT index_name/_doc/_id?op_type=create创建时，URI中显示指定_create，此时如果该_id的文档已经存在，操作会失败。
#1.create document. 指定 _id 如果已经存在，就报错
PUT users/_create/1
{
"user" : "Jack",
"post_date" : "2019-05-15T14:12:12",
"message" : "trying out Elasticsearch"
}
#2.create document. 指定_id。如果_id已经存在，报错
PUT users/_doc/1?op_type=create
{
"user" : "Jack",
"post_date" : "2019-05-15T14:12:12",
"message" : "trying out Elasticsearch"
}#如果_id已经存在报错信息，如下：
{
"error": {
"root_cause": [
{
"type": "version_conflict_engine_exception",
"reason": "[1]: version conflict, document already exists (current version [1])",
"index_uuid": "ohLNyzUmTv6cm-Ih9kH0bw",
"shard": "0",
"index": "users"
}
],
"type": "version_conflict_engine_exception",
"reason": "[1]: version conflict, document already exists (current version [1])",
"index_uuid": "ohLNyzUmTv6cm-Ih9kH0bw",
"shard": "0",
"index": "users"
},
"status": 409
}Index 文档
Index和Create不一样的地方：如果文档不存在，就索引新的文档。否则现有的文档会被删除，新的文档被索引，版本信息+1。使用PUT index_name/_doc/_id。
PUT users/_doc/1
{
"user" : "Mike"
}#返回结果
{
"_index" : "users",
"_type" : "_doc",
"_id" : "1",
"_version" : 3, #版本增加
"result" : "updated",
"_shards" : {
"total" : 2,
"successful" : 1,
"failed" : 0
},
"_seq_no" : 4,
"_primary_term" : 2
}Update 文档
Update方法不会删除原来的文档，而是实现真正的数据更新，更新的文档必须存在，更新的内容需要包含在doc中。
#更新文档API POST index_name/_update/_id { "doc":{ "field1":"value1", "field2":"value2" } }
#更新_id=1文档
POST users/_update/1
{
"doc":{
"post_date" : "2019-05-15T14:12:12",
"message" : "trying out Elasticsearch"
}
}Get 文档
根据文档ID，获取相应文档信息，GET index_name/_doc/_id
#Get the document by ID
GET users/_doc/1#返回结果
{
"_index" : "users",
"_type" : "_doc",
"_id" : "1",
"_version" : 1,
"_seq_no" : 2,
"_primary_term" : 1,
"found" : true,
"_source" : {
"user" : "Jack",
"post_date" : "2019-05-15T14:12:12",
"message" : "trying out Elasticsearch"
}
}Delete 文档
根据文档ID，删除相应文档信息，DELETE index_name/_doc/_id
# 删除文档
DELETE users/_doc/1批量操作-bulk
批量操作，可以减少网络连接所产生的开销，提高性能。
- 支持在一次API调用中，对不同的索引进行操作。
- 支持四种类型操作：
Index,Create,Update,Delete。 - 可以在URI中指定Index，也可以在请求中指定。
- 操作中单条操作失败，并不会影响其他操作。
- 返回结果包括了每一条操作执行的结果。
- 不要发送过多数据，一般建议是1000-5000个文档，如果你的文档很大，可以适当减少队列，大小建议是5-15MB，默认不能超过100M，会报错。
### Bulk 操作
POST _bulk
{ "index" : { "_index" : "test", "_id" : "1" } }
{ "field1" : "value1" }
{ "delete" : { "_index" : "test", "_id" : "2" } }
{ "create" : { "_index" : "test2", "_id" : "3" } }
{ "field1" : "value3" }
{ "update" : {"_id" : "1", "_index" : "test"} }
{ "doc" : {"field2" : "value2"} }#返回结果
{
"took" : 227,
"errors" : false,
"items" : [
{
"index" : {
"_index" : "test",
"_type" : "_doc",
"_id" : "1",
"_version" : 1,
"result" : "created",
"_shards" : {
"total" : 2,
"successful" : 1,
"failed" : 0
},
"_seq_no" : 0,
"_primary_term" : 1,
"status" : 201
}
},
{
"delete" : {
"_index" : "test",
"_type" : "_doc",
"_id" : "2",
"_version" : 1,
"result" : "not_found",
"_shards" : {
"total" : 2,
"successful" : 1,
"failed" : 0
},
"_seq_no" : 1,
"_primary_term" : 1,
"status" : 404
}
},
{
"create" : {
"_index" : "test2",
"_type" : "_doc",
"_id" : "3",
"_version" : 1,
"result" : "created",
"_shards" : {
"total" : 2,
"successful" : 1,
"failed" : 0
},
"_seq_no" : 0,
"_primary_term" : 1,
"status" : 201
}
},
{
"update" : {
"_index" : "test",
"_type" : "_doc",
"_id" : "1",
"_version" : 2,
"result" : "updated",
"_shards" : {
"total" : 2,
"successful" : 1,
"failed" : 0
},
"_seq_no" : 2,
"_primary_term" : 1,
"status" : 200
}
}
]
}批量读取-mget
mget 是通过文档_id列表得到文档信息。
### mget 操作
GET /_mget
{
"docs" : [
{
"_index" : "test",
"_id" : "1"
},
{
"_index" : "test",
"_id" : "2"
}
]
}
#URI中指定index
GET /test/_mget
{
"docs" : [
{
"_id" : "1"
},
{
"_id" : "2"
}
]
}
GET /_mget
{
"docs" : [
{
"_index" : "test",
"_id" : "1",
"_source" : false
},
{
"_index" : "test",
"_id" : "2",
"_source" : ["field3", "field4"]
},
{
"_index" : "test",
"_id" : "3",
"_source" : {
"include": ["user"],
"exclude": ["user.location"]
}
}
]
}#返回结果
{
"docs" : [
{
"_index" : "test",
"_type" : "_doc",
"_id" : "1",
"_version" : 4,
"_seq_no" : 5,
"_primary_term" : 1,
"found" : true,
"_source" : {
"field1" : "value1",
"field2" : "value2"
}
},
{
"_index" : "test",
"_type" : "_doc",
"_id" : "2",
"found" : false
}
]
}批量查询-msearch
msearch 是根据查询条件，搜索到相应文档。
POST kibana_sample_data_ecommerce/_msearch
{}
{"query" : {"match_all" : {}},"size":1}
{"index" : "kibana_sample_data_flights"}
{"query" : {"match_all" : {}},"size":2}常见错误返回说明
| 问题 | 原因 |
|---|---|
| 无法连接 | 网络故障或集群挂了 |
| 连接无法关闭 | 网络故障或节点出错 |
| 429 | 集群过于繁忙 |
| 4xx | 请求体格式有错 |
| 500 | 集群内部错误 |