elasticsearch从入门到入门系列（四）---搜索高级使用
1.es索引的别名使用
- 在开发中，随着业务需求的迭代，较⽼的业务逻辑就要⾯临更新甚⾄是重构，⽽对于es来说，为了 适应新的业务逻辑，可能就要对原有的索引做⼀些修改，⽐如对某些字段做调整，甚⾄是重建索 引。⽽做这些操作的时候，可能会对业务造成影响，甚⾄是停机调整等问题。由此，es提供了索引 别名来解决这些问题。 索引别名就像⼀个快捷⽅式或是软连接，可以指向⼀个或多个索引，也可 以给任意⼀个需要索引名的API来使⽤。别名的应⽤为程序提供了极⼤地灵活性
- 别名查询
GET /nba/_alias
GET /_alias- 新增别名
POST /_aliases
{
"actions": [
{
"add": {
"index": "nba",
"alias": "nba_v1.0"
}
}
]
}- 删除别名
POST /_aliases
{
"actions": [
{
"remove": {
"index": "nba",
"alias": "nba_v1.0"
}
}
]
}DELETE /nba/_alias/nba_v1.1
- 重命名
POST /_aliases
{
"actions": [
{
"remove": {
"index": "nba",
"alias": "nba_v1.0"
}
},
{
"add": {
"index": "nba",
"alias": "nba_v2.0"
}
}
]
}- 为多个索引指定⼀个别名
POST /_aliases
{
"actions": [
{
"add": {
"index": "nba",
"alias": "national_player"
}
},
{
"add": {
"index": "wnba",
"alias": "national_player"
}
}
]
}- 为同个索引指定多个别名
POST /_aliases
{
"actions": [
{
"add": {
"index": "nba",
"alias": "nba_v2.1"
}
},
{
"add": {
"index": "nba",
"alias": "nba_v2.2"
}
}
]
}- 通过别名读索引
当别名指定了⼀个索引，则查出⼀个索引
GET /nba_v2.1
当别名指定了多个索引，则查出多个索引
GET /national_player
- 通过别名写索引
当别名指定了⼀个索引，则可以做写的操作
POST /nba_v2.1/_doc/566
{
"countryEn": "Croatia",
"teamName": "快船",
"birthDay": 858661200000,
"country": "克罗地亚",
"teamCityEn": "LA",
"code": "ivica_zubac",
"displayAffiliation": "Croatia",
"displayName": "伊维察 祖巴茨哥哥",
"schoolType": "",
"teamConference": "⻄部",
"teamConferenceEn": "Western",
"weight": "108.9 公⽄",
"teamCity": "洛杉矶",
"playYear": 3,
"jerseyNo": "40",
"teamNameEn": "Clippers",
"draft": 2016,
"displayNameEn": "Ivica Zubac",
"heightValue": 2.16,
"birthDayStr": "1997-03-18",
"position": "中锋",
"age": 22,
"playerId": "1627826"
}- 当别名指定了多个索引，可以指定写某个索引
POST /_aliases
{
"actions": [
{
"add": {
"index": "nba",
"alias": "national_player",
"is_write_index": true
}
},
{
"add": {
"index": "wnba",
"alias": "national_player"
}
}
]
}POST /national_player/_doc/566
{
"countryEn": "Croatia",
"teamName": "快船",
"birthDay": 858661200000,
"country": "克罗地亚",
"teamCityEn": "LA",
"code": "ivica_zubac",
"displayAffiliation": "Croatia",
"displayName": "伊维察 祖巴茨妹妹",
"schoolType": "",
"teamConference": "⻄部",
"teamConferenceEn": "Western",
"weight": "108.9 公⽄",
"teamCity": "洛杉矶",
"playYear": 3,
"jerseyNo": "40",
"teamNameEn": "Clippers",
"draft": 2016,
"displayNameEn": "Ivica Zubac",
"heightValue": 2.16,
"birthDayStr": "1997-03-18",
"position": "中锋",
"age": 22,
"playerId": "1627826"
}2.es之如何重建索引
- 步骤
- nba取⼀个别名nba_latest, nba_latest作为对外使⽤
- 新增⼀个索引nba_20220101，结构复制于nba索引，根据业务要求修改字段
- 将nba数据同步到nba_20220101
- 给nba_20220101添加别名nba_latest，删除nba别名nba_latest
- 删除nba索引
- 案例
1.我们对外提供访问nba索引时使⽤的是nba_latest别名
2.新增⼀个索引(⽐如修改字段类型，jerseyNo改成keyword类型)
PUT /nba_20220101
{
"mappings": {
"properties": {
"age": {
"type": "integer"
},
"birthDay": {
"type": "date"
},
"birthDayStr": {
"type": "keyword"
},
"code": {
"type": "text"
},
"country": {
"type": "keyword"
},
"countryEn": {
"type": "keyword"
},
"displayAffiliation": {
"type": "text"
},
"displayName": {
"type": "text"
},
"displayNameEn": {
"type": "text"
},
"draft": {
"type": "long"
},
"heightValue": {
"type": "float"
},
"jerseyNo": {
"type": "keyword"
},
"playYear": {
"type": "long"
},
"playerId": {
"type": "keyword"
},
"position": {
"type": "text"
},
"schoolType": {
"type": "text"
},
"teamCity": {
"type": "text"
},
"teamCityEn": {
"type": "text"
},
"teamConference": {
"type": "keyword"
},
"teamConferenceEn": {
"type": "keyword"
},
"teamName": {
"type": "keyword"
},
"teamNameEn": {
"type": "keyword"
},
"weight": {
"type": "text"
}
}
}
}
3.将旧索引数据copy到新索引
3.1 同步等待，接⼝将会在 reindex 结束后返回
POST /_reindex
{
"source": {
"index": "nba"
},
"dest": {
"index": "nba_20220101"
}
}
3.2异步执⾏，如果 reindex 时间过⻓，建议加上 wait_for_completion=false 的参数条件，
这样 reindex 将直接返回 taskId
POST /_reindex?wait_for_completion=false
{
"source": {
"index": "nba"
},
"dest": {
"index": "nba_20220101"
}
}
4.替换别名
POST /_aliases
{
"actions": [
{
"add": {
"index": "nba_20220101",
"alias": "nba_latest"
}
},
{
"remove": {
"index": "nba",
"alias": "nba_latest"
}
}
]
}
5.删除旧索引
DELETE /nba
6.通过别名访问新索引
POST /nba_latest/_search
{
"query": {
"match": {
"displayNameEn": "james"
}
}
}
3.es之refresh操作
- 理想的搜索
- 新的数据⼀添加到索引中⽴⻢就能搜索到，但是真实情况不是这样的。
- 我们使⽤链式命令请求，先添加⼀个⽂档，再⽴刻搜索
curl -X PUT localhost:9200/star/_doc/888 -H 'Content-Type:
application/json' -d '{ "displayName": "蔡徐坤" }'
curl -X GET localhost:9200/star/_doc/_search?pretty- 强制刷新
curl -X PUT localhost:9200/star/_doc/666?refresh -H 'Content-Type:
application/json' -d '{ "displayName": "杨超越" }'
curl -X GET localhost:9200/star/_doc/_search?pretty- 修改默认更新时间(默认时间是1s)
PUT /star/_settings
{
"index": {
"refresh_interval": "5s"
}
}- 将refresh关闭
PUT /star/_settings
{
"index": {
"refresh_interval": "-1"
}
}4.es之⾼亮查询
- ⾼亮查询
POST /nba_latest/_search
{
"query": {
"match": {
"displayNameEn": "james"
}
},
"highlight": {
"fields": {
"displayNameEn": { }
}
}
}- ⾃定义⾼亮查询
POST /nba_latest/_search
{
"query": {
"match": {
"displayNameEn": "james"
}
},
"highlight": {
"fields": {
"displayNameEn": {
"pre_tags": [
""
],
"post_tags": [
"
"
]
}
}
}
}
5.es查询建议
- 查询建议，是为了给⽤户提供更好的搜索体验。包括：词条检查，⾃动补全。
- Term suggester
- term 词条建议器，对给输⼊的⽂本进⾏分词，为每个分词提供词项建议
POST /nba_latest/_search
{
"suggest": {
"my-suggestion": {
"text": "jamse hardne",
"term": {
"suggest_mode": "missing",
"field": "displayNameEn"
}
}
}
}- Phrase suggester
- phrase 短语建议，在term的基础上，会考量多个term之间的关系，⽐如是否同时出现在索 引的原⽂⾥，相邻程度，以及词频等
POST /nba_latest/_search
{
"suggest": {
"my-suggestion": {
"text": "jamse harden",
"phrase": {
"field": "displayNameEn"
}
}
}
}- Completion suggester
- Completion 完成建议
POST /nba_latest/_search
{
"suggest": {
"my-suggestion": {
"text": "Miam",
"completion": {
"field": "teamCityEn"
}
}
}
}