400-139-9200
全文搜索 #
全文搜索是对存储的单个文档进行搜索，这与基于数据库中的原始文本的常规搜索有所区别。全文搜索尝试通过检查每个文档中的所有单词来匹配搜索条件。 在 Easysearch 中，提供的全文查询使你能够搜索在索引过程中分析的文本字段。
Match Query #
在 Easysearch 中，Match 查询是执行全文搜索的标准查询。MATCHQUERY 和 MATCH_QUERY 都是用于执行匹配查询的函数。
示例 1 #
这两个函数都可以接受字段名称作为第一个参数，文本作为第二个参数。
SQL query:
POST /_sql
{
"query" : """
SELECT account_number, address
FROM accounts
WHERE MATCH_QUERY(address, 'Holmes')
"""
}
解释：
{
"from" : 0,
"size" : 200,
"query" : {
"bool" : {
"filter" : [
{
"bool" : {
"must" : [
{
"match" : {
"address" : {
"query" : "Holmes",
"operator" : "OR",
"prefix_length" : 0,
"max_expansions" : 50,
"fuzzy_transpositions" : true,
"lenient" : false,
"zero_terms_query" : "NONE",
"auto_generate_synonyms_phrase_query" : true,
"boost" : 1.0
}
}
}
],
"adjust_pure_negative" : true,
"boost" : 1.0
}
}
],
"adjust_pure_negative" : true,
"boost" : 1.0
}
},
"_source" : {
"includes" : [
"account_number",
"address"
],
"excludes" : [ ]
}
}
结果集：
| account_number | address |
|---|---|
| 1 | 880 Holmes Lane |
示例 2 #
这两个函数也可以接受单个参数，并按以下方式使用。
SQL query:
POST /_sql
{
"query" : """
SELECT account_number, address
FROM accounts
WHERE address = MATCH_QUERY('Holmes')
"""
}
解释：
{
"from" : 0,
"size" : 200,
"query" : {
"bool" : {
"filter" : [
{
"bool" : {
"must" : [
{
"match" : {
"address" : {
"query" : "Holmes",
"operator" : "OR",
"prefix_length" : 0,
"max_expansions" : 50,
"fuzzy_transpositions" : true,
"lenient" : false,
"zero_terms_query" : "NONE",
"auto_generate_synonyms_phrase_query" : true,
"boost" : 1.0
}
}
}
],
"adjust_pure_negative" : true,
"boost" : 1.0
}
}
],
"adjust_pure_negative" : true,
"boost" : 1.0
}
},
"_source" : {
"includes" : [
"account_number",
"address"
],
"excludes" : [ ]
}
}
结果集：
| account_number | address |
|---|---|
| 1 | 880 Holmes Lane |
Multi-match Query #
除了针对单个字段进行匹配查询外，您还可以使用多个字段搜索文本。为此，提供了函数 MULTI_MATCH、 MULTIMATCH 和 MULTIMATCHQUERY。
示例 #
每个前面提到的函数都接受一个 query 参数用于指定要搜索的文本，以及一个 fields 参数用于指定要搜索的字段名称或模式。例如，以下查询在名为 accounts 的索引中搜索名字或姓氏为 ‘Dale’ 的文档：
SQL query:
POST /_sql
{
"query" : """
SELECT firstname, lastname
FROM accounts
WHERE MULTI_MATCH('query'='Dale', 'fields'='*name')
"""
}
解释：
{
"from" : 0,
"size" : 200,
"query" : {
"bool" : {
"filter" : [
{
"bool" : {
"must" : [
{
"multi_match" : {
"query" : "Dale",
"fields" : [
"*name^1.0"
],
"type" : "best_fields",
"operator" : "OR",
"slop" : 0,
"prefix_length" : 0,
"max_expansions" : 50,
"zero_terms_query" : "NONE",
"auto_generate_synonyms_phrase_query" : true,
"fuzzy_transpositions" : true,
"boost" : 1.0
}
}
],
"adjust_pure_negative" : true,
"boost" : 1.0
}
}
],
"adjust_pure_negative" : true,
"boost" : 1.0
}
},
"_source" : {
"includes" : [
"firstname",
"lastname"
],
"excludes" : [ ]
}
}
结果集：
| firstname | lastname |
|---|---|
| Dale | Adams |
Query String 查询 #
查询字符串查询是基于 Lucene 查询字符串语法解析和拆分提供的查询字符串。这种小语言支持逻辑连接词、通配符、正则表达式和邻近搜索。更多详细信息请参阅官方文档。请注意，如果在查询字符串中存在任何无效语法，则会抛出错误。
示例 #
QUERY 函数接受查询字符串，并分别对符合查询字符串的文档返回true或false。
SQL query:
POST /_sql
{
"query" : """
SELECT account_number, address
FROM accounts
WHERE QUERY('address:Lane OR address:Street')
"""
}
解释：
{
"from" : 0,
"size" : 200,
"query" : {
"bool" : {
"filter" : [
{
"bool" : {
"must" : [
{
"query_string" : {
"query" : "address:Lane OR address:Street",
"fields" : [ ],
"type" : "best_fields",
"default_operator" : "or",
"max_determinized_states" : 10000,
"enable_position_increments" : true,
"fuzziness" : "AUTO",
"fuzzy_prefix_length" : 0,
"fuzzy_max_expansions" : 50,
"phrase_slop" : 0,
"escape" : false,
"auto_generate_synonyms_phrase_query" : true,
"fuzzy_transpositions" : true,
"boost" : 1.0
}
}
],
"adjust_pure_negative" : true,
"boost" : 1.0
}
}
],
"adjust_pure_negative" : true,
"boost" : 1.0
}
},
"_source" : {
"includes" : [
"account_number",
"address"
],
"excludes" : [ ]
}
}
结果集：
| account_number | address |
|---|---|
| 1 | 880 Holmes Lane |
| 6 | 671 Bristol Street |
| 13 | 789 Madison Street |
Match Phrase 查询 #
匹配短语查询与匹配查询类似，但用于匹配确切的短语。为此，提供了函数 MATCHPHRASE、 MATCH_PHRASE 和 MATCHPHRASEQUERY。
示例 #
SQL query:
POST /_sql
{
"query" : """
SELECT account_number, address
FROM accounts
WHERE MATCH_PHRASE(address, '880 Holmes Lane')
"""
}
解释：
{
"from" : 0,
"size" : 200,
"query" : {
"bool" : {
"filter" : [
{
"bool" : {
"must" : [
{
"match_phrase" : {
"address" : {
"query" : "880 Holmes Lane",
"slop" : 0,
"zero_terms_query" : "NONE",
"boost" : 1.0
}
}
}
],
"adjust_pure_negative" : true,
"boost" : 1.0
}
}
],
"adjust_pure_negative" : true,
"boost" : 1.0
}
},
"_source" : {
"includes" : [
"account_number",
"address"
],
"excludes" : [ ]
}
}
结果集：
| account_number | address |
|---|---|
| 1 | 880 Holmes Lane |
Score Query #
Easysearch支持将过滤查询包装起来，以便在每个匹配的文档中返回相关性得分。可以使用 SCORE、 SCOREQUERY 和 SCORE_QUERY 来实现此功能。
示例 #
第一个参数是匹配查询表达式，第二个参数是一个可选的浮点数，用于提高得分。默认值为1.0。除此之外，隐式变量_score也可用于返回每个文档的得分或用于排序。
SQL query:
POST /_sql
{
"query" : """
SELECT account_number, address, _score
FROM accounts
WHERE SCORE(MATCH_QUERY(address, 'Lane'), 0.5) OR
SCORE(MATCH_QUERY(address, 'Street'), 100)
ORDER BY _score
"""
}
解释：
{
"from" : 0,
"size" : 200,
"query" : {
"bool" : {
"must" : [
{
"bool" : {
"should" : [
{
"constant_score" : {
"filter" : {
"match" : {
"address" : {
"query" : "Lane",
"operator" : "OR",
"prefix_length" : 0,
"max_expansions" : 50,
"fuzzy_transpositions" : true,
"lenient" : false,
"zero_terms_query" : "NONE",
"auto_generate_synonyms_phrase_query" : true,
"boost" : 1.0
}
}
},
"boost" : 0.5
}
},
{
"constant_score" : {
"filter" : {
"match" : {
"address" : {
"query" : "Street",
"operator" : "OR",
"prefix_length" : 0,
"max_expansions" : 50,
"fuzzy_transpositions" : true,
"lenient" : false,
"zero_terms_query" : "NONE",
"auto_generate_synonyms_phrase_query" : true,
"boost" : 1.0
}
}
},
"boost" : 100.0
}
}
],
"adjust_pure_negative" : true,
"boost" : 1.0
}
}
],
"adjust_pure_negative" : true,
"boost" : 1.0
}
},
"_source" : {
"includes" : [
"account_number",
"address",
"_score"
],
"excludes" : [ ]
},
"sort" : [
{
"_score" : {
"order" : "asc"
}
}
]
}
结果集：
| account_number | address | _score |
|---|---|---|
| 1 | 880 Holmes Lane | 0.5 |
| 6 | 671 Bristol Street | 100 |
| 13 | 789 Madison Street | 100 |
