在 NEST 中,如何根据术语列表动态构建查询?
in NEST, how do I dynamically build a query from a list of terms?
假设我的用户提供了我收集到 array/list 中的搜索词列表,现在我想使用 MatchPhrase 将这些 OR-wise 组合成一个 NEST 查询。我该怎么做? (单个)搜索词的代码如下所示:
var search = client.Search<ElasticRequirement>(s => s
.Query(q =>
q.MatchPhrase(m => m.OnField(f => f.Title).Query(term.ToLower()).Slop(slop))
|| q.MatchPhrase(m => m.OnField(f => f.Description).Query(text).Slop(slop))
)
.LowercaseExpandedTerms()
.Explain()
.Query(q => q.Fuzzy(f => f.PrefixLength(1).OnField(c => c.Title).OnField(c => c.Description)))
);
很好,但我需要为提供的每个搜索词应用一次相同的 MatchPhrase 过滤器。非常感谢任何帮助。
您可以使用 bool
should
表达式来动态构建查询。我将在下面提供完整的解决方案。使用适当的参数调用 BuildQuery()
方法。
ISearchResponse<ElasticRequirement> BuildQuery(IElasticClient client, IEnumerable<string> terms, int slop)
{
return client.Search<ElasticRequirement>(s => s
.Query(q => q
.Bool(b => b
.Should(terms.Select(t => BuildPhraseQueryContainer(q, t, slop)).ToArray())))
.LowercaseExpandedTerms()
.Explain()
.Query(q => q.Fuzzy(f => f.PrefixLength(1).OnField(c => c.Title).OnField(c => c.Description))));
}
QueryContainer BuildPhraseQueryContainer(QueryDescriptor<ElasticRequirement> qd, string term, int slop)
{
return qd.MatchPhrase(m => m.OnField(f => f.Title).Query(term.ToLower()).Slop(slop)) ||
qd.MatchPhrase(m => m.OnField(f => f.Description).Query(term.ToLower()).Slop(slop));
}
对于 terms = {"term1", "term2", "term3"}
和 slop = 0
,将由我的代码构建的 Elasticsearch 搜索 JSON 命令如下:
{
"explain": true,
"query": {
"bool": {
"should": [
{
"bool": {
"should": [
{
"match": {
"title": {
"type": "phrase",
"query": "term1",
"slop": 0
}
}
},
{
"match": {
"description": {
"type": "phrase",
"query": "term1",
"slop": 0
}
}
}
]
}
},
{
"bool": {
"should": [
{
"match": {
"title": {
"type": "phrase",
"query": "term2",
"slop": 0
}
}
},
{
"match": {
"description": {
"type": "phrase",
"query": "term2",
"slop": 0
}
}
}
]
}
},
{
"bool": {
"should": [
{
"match": {
"title": {
"type": "phrase",
"query": "term3",
"slop": 0
}
}
},
{
"match": {
"description": {
"type": "phrase",
"query": "term3",
"slop": 0
}
}
}
]
}
}
]
}
}
}
您可以调整此代码,使所有 match
命令都在同一个 should
节点下。我会把它留给你去弄清楚:)
假设我的用户提供了我收集到 array/list 中的搜索词列表,现在我想使用 MatchPhrase 将这些 OR-wise 组合成一个 NEST 查询。我该怎么做? (单个)搜索词的代码如下所示:
var search = client.Search<ElasticRequirement>(s => s
.Query(q =>
q.MatchPhrase(m => m.OnField(f => f.Title).Query(term.ToLower()).Slop(slop))
|| q.MatchPhrase(m => m.OnField(f => f.Description).Query(text).Slop(slop))
)
.LowercaseExpandedTerms()
.Explain()
.Query(q => q.Fuzzy(f => f.PrefixLength(1).OnField(c => c.Title).OnField(c => c.Description)))
);
很好,但我需要为提供的每个搜索词应用一次相同的 MatchPhrase 过滤器。非常感谢任何帮助。
您可以使用 bool
should
表达式来动态构建查询。我将在下面提供完整的解决方案。使用适当的参数调用 BuildQuery()
方法。
ISearchResponse<ElasticRequirement> BuildQuery(IElasticClient client, IEnumerable<string> terms, int slop)
{
return client.Search<ElasticRequirement>(s => s
.Query(q => q
.Bool(b => b
.Should(terms.Select(t => BuildPhraseQueryContainer(q, t, slop)).ToArray())))
.LowercaseExpandedTerms()
.Explain()
.Query(q => q.Fuzzy(f => f.PrefixLength(1).OnField(c => c.Title).OnField(c => c.Description))));
}
QueryContainer BuildPhraseQueryContainer(QueryDescriptor<ElasticRequirement> qd, string term, int slop)
{
return qd.MatchPhrase(m => m.OnField(f => f.Title).Query(term.ToLower()).Slop(slop)) ||
qd.MatchPhrase(m => m.OnField(f => f.Description).Query(term.ToLower()).Slop(slop));
}
对于 terms = {"term1", "term2", "term3"}
和 slop = 0
,将由我的代码构建的 Elasticsearch 搜索 JSON 命令如下:
{
"explain": true,
"query": {
"bool": {
"should": [
{
"bool": {
"should": [
{
"match": {
"title": {
"type": "phrase",
"query": "term1",
"slop": 0
}
}
},
{
"match": {
"description": {
"type": "phrase",
"query": "term1",
"slop": 0
}
}
}
]
}
},
{
"bool": {
"should": [
{
"match": {
"title": {
"type": "phrase",
"query": "term2",
"slop": 0
}
}
},
{
"match": {
"description": {
"type": "phrase",
"query": "term2",
"slop": 0
}
}
}
]
}
},
{
"bool": {
"should": [
{
"match": {
"title": {
"type": "phrase",
"query": "term3",
"slop": 0
}
}
},
{
"match": {
"description": {
"type": "phrase",
"query": "term3",
"slop": 0
}
}
}
]
}
}
]
}
}
}
您可以调整此代码,使所有 match
命令都在同一个 should
节点下。我会把它留给你去弄清楚:)