43 lines
1.4 KiB
Plaintext
43 lines
1.4 KiB
Plaintext
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[[query-dsl-span-field-masking-query]]
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=== Span Field Masking Query
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Wrapper to allow span queries to participate in composite single-field span queries by 'lying' about their search field. The span field masking query maps to Lucene's `SpanFieldMaskingQuery`
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This can be used to support queries like `span-near` or `span-or` across different fields, which is not ordinarily permitted.
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Span field masking query is invaluable in conjunction with *multi-fields* when same content is indexed with multiple analyzers. For instance we could index a field with the standard analyzer which breaks text up into words, and again with the english analyzer which stems words into their root form.
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Example:
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[source,js]
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--------------------------------------------------
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GET /_search
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{
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"query": {
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"span_near": {
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"clauses": [
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{
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"span_term": {
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"text": "quick brown"
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}
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},
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{
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"field_masking_span": {
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"query": {
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"span_term": {
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"text.stems": "fox"
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}
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},
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"field": "text"
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}
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}
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],
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"slop": 5,
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"in_order": false
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}
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}
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}
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--------------------------------------------------
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// CONSOLE
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Note: as span field masking query returns the masked field, scoring will be done using the norms of the field name supplied. This may lead to unexpected scoring behaviour.
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