23种非常有用的ElasticSearch查询例子(2) ElasticSearch 2016-08-16 22:08:27 1808
0评论 下载为PDF本系列文章将展示
ElasticSearch中23种非常有用的查询使用方法。由于篇幅原因，本系列文章分为六篇，本文是此系列的第二篇文章。欢迎关注大数据技术博客微信公共账号:iteblog_hadoop。
《23种非常有用的ElasticSearch查询例子(1)》《23种非常有用的ElasticSearch查询例子(2)》《23种非常有用的ElasticSearch查询例子(3)》《23种非常有用的ElasticSearch查询例子(4)》《23种非常有用的ElasticSearch查询例子(5)》《23种非常有用的ElasticSearch查询例子(6)》文章目录
1 Fuzzy Queries（模糊查询）2 Wildcard Query(通配符查询)3 Regexp Query(正则表达式查询)Fuzzy Queries（模糊查询）
模糊查询可以在Match和 Multi-Match查询中使用以便解决拼写的错误，模糊度是基于Levenshtein distance计算与原单词的距离。使用如下：
curl -XGET '
https://www.iteblog.com:9200/iteblog_book_index/book/_search' -d '
{
"query": {
"multi_match" : {
"query" : "comprihensiv guide",
"fields": ["title", "summary"],
"fuzziness": "AUTO"
}
},
"_source": ["title", "summary", "publish_date"],
"size": 1
}'
[返回结果]
{
"took": 208,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"failed": 0
},
"hits": {
"total": 2,
"max_score": 0.5961596,
"hits": [
{
"_index": "iteblog_book_index",
"_type": "book",
"_id": "4",
"_score": 0.5961596,
"_source": {
"summary": "Comprehensive guide to implementing a scalable search engine using Apache Solr",
"title": "Solr in Action",
"publish_date": "2014-04-05"
}
}
]
}
}
需要注意：上面我们将fuzziness的值指定为AUTO，其在term的长度大于5的时候相当于指定值为2。然而80%的人拼写错误的编辑距离(edit distance)为1，所有如果你将fuzziness设置为1可能会提高你的搜索性能。具体的可以参考Elasticsearch权威指南相关章节。
Wildcard Query(通配符查询)
通配符查询允许我们指定一个模式来匹配，而不需要指定完整的trem。?将会匹配如何字符；*将会匹配零个或者多个字符。比如我们想查找所有作者名字中以t字符开始的记录，我们可以如下使用：
如果想及时了解Spark、Hadoop或者Hbase相关的文章，欢迎关注微信公共账号：iteblog_hadoop
curl -XGET '
https://www.iteblog.com:9200/iteblog_book_index/book/_search' -d '
{
"query": {
"wildcard" : {
"authors" : "t*"
}
},
"_source": ["title", "authors"],
"highlight": {
"fields" : {
"authors" : {}
}
}
}'
[返回结果]
{
"took": 37,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"failed": 0
},
"hits": {
"total": 3,
"max_score": 1,
"hits": [
{
"_index": "iteblog_book_index",
"_type": "book",
"_id": "1",
"_score": 1,
"_source": {
"authors": [
"clinton gormley",
"zachary tong"
],
"title": "Elasticsearch: The Definitive Guide"
},
"highlight": {
"authors": [
"zachary <em>tong</em>"
]
}
},
{
"_index": "iteblog_book_index",
"_type": "book",
"_id": "2",
"_score": 1,
"_source": {
"authors": [
"grant ingersoll",
"thomas morton",
"drew farris"
],
"title": "Taming Text: How to Find, Organize, and Manipulate It"
},
"highlight": {
"authors": [
"<em>thomas</em> morton"
]
}
},
{
"_index": "iteblog_book_index",
"_type": "book",
"_id": "4",
"_score": 1,
"_source": {
"authors": [
"trey grainger",
"timothy potter"
],
"title": "Solr in Action"
},
"highlight": {
"authors": [
"<em>trey</em> grainger",
"<em>timothy</em> potter"
]
}
}
]
}
}
Regexp Query(正则表达式查询)
ElasticSearch还支持正则表达式查询，此方式提供了比通配符查询更加复杂的模式。比如我们先查找作者名字以t字符开头，中间是若干个a-z之间的字符，并且以字符y结束的记录，可以如下查询：
curl -XGET '
https://www.iteblog.com:9200/iteblog_book_index/book/_search' -d '
{
"query": {
"regexp" : {
"authors" : "t[a-z]*y"
}
},
"_source": ["title", "authors"],
"highlight": {
"fields" : {
"authors" : {}
}
}
}'
{
"took": 25,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"failed": 0
},
"hits": {
"total": 1,
"max_score": 1,
"hits": [
{
"_index": "iteblog_book_index",
"_type": "book",
"_id": "4",
"_score": 1,
"_source": {
"authors": [
"trey grainger",
"timothy potter"
],
"title": "Solr in Action"
},
"highlight": {
"authors": [
"<em>trey</em> grainger",
"<em>timothy</em> potter"
]
}
}
]
}
}
限于篇幅的原因，本系列文章分为六部分，欢迎关注过往记忆大数据技术博客及时了解大数据相关文章，微信公共账号：iteblog_hadoop。
本站仅提供存储服务，所有内容均由用户发布，如发现有害或侵权内容，请
点击举报。
