Dictionary
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| Efficiency level | ||
| Rank | Search complexity | Description |
|---|---|---|
| 1 | O(1) in memory | Extremely fast (e.g. typically <100 ms) |
| 2 | O(1) | Fast (e.g. typically <500 ms) |
| 3 | O(log(n))pro rata prefix_length | Fast (e.g. typically < 1000 ms) |
| 4 | xtables couning | Fast enough (e.g. typically < 1000 ms) |
| 5 | O(n) | Slow (up to minutes on big datasets) |
Use cases that will not be effective in Elastic
| Function | Efficiency level | Indexed instance data | Search input text | Documentation |
|---|
| Full text search for terms with stemming and stop-word filtering | 2 | { "title": "The Lord of the Rings", ...} | title = Lords of the Ring | |
| Keyword search (aka exact match). | 2 | {"barcode" : "12345678", ... } | barcode = 12345678 | |
Full text Search for terms with over all text fields and exact match for all keyword fields |
. | 2 | { "title": "The Lord of the Rings", "publicNote" : "silver covering", "barcode" : "12345678" ... |
} | Lord of the Ring silver covers or Lord of the Ring 12345678 | Note: Stemming and Analyzing of various languages is supported, but we need to do use it only for required predefined list of languages. | ||
| Range filter | 2 | { "createdDate" : "12-12-2020", ...} | createdDate > 10-12-2020 | |
| Autocomplete | 1 | { "The Lord of the Rings" : "12-12-2020", ...} | input: Lord of, output: The Lord of the Rings | From |
| Facets |
| 4 | {"effectiveLocation" : "some_uuid"} | Output facets on the right-hand side | ||
| Wildcard search with * on left | in most cases 3, can be 2 if index_prefixes is |
| specified | {"hrid" : "12345678", ... } | hrid = 12345* | https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-prefix-query.html. The query could be slow, if small number of characters is specified for query and we need to calculate all matches, because we need accurate counts | |
| Wildcard search with * on right | 3 | {"hrid" : "12345678", ... } | hrid = *2345678 | https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-prefix-query.html |
| Wildcard search with * on left and right or in the middle | 5, but there can be optimizations that make it 2 for certain cases | {"hrid" : "12345678", ... } | hrid = *34567* hrid = 1234*78 | https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-wildcard-query.html or https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-regexp-query.html |