61 lines
1.5 KiB
Plaintext
61 lines
1.5 KiB
Plaintext
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[[geohash-precision]]
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=== `geohash_precision`
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Geohashes are a form of lat/lon encoding which divides the earth up into
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a grid. Each cell in this grid is represented by a geohash string. Each
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cell in turn can be further subdivided into smaller cells which are
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represented by a longer string. So the longer the geohash, the smaller
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(and thus more accurate) the cell is.
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The `geohash_precision` setting controls the length of the geohash that is
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indexed when the <<geohash,`geohash`>> option is enabled, and the maximum
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geohash length when the <<geohash-prefix,`geohash_prefix`>> option is enabled.
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It accepts:
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* a number between 1 and 12 (default), which represents the length of the geohash.
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* a <<distance-units,distance>>, e.g. `1km`.
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If a distance is specified, it will be translated to the smallest
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geohash-length that will provide the requested resolution.
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For example:
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[source,js]
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--------------------------------------------------
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PUT my_index
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{
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"mappings": {
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"my_type": {
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"properties": {
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"location": {
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"type": "geo_point",
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"geohash_prefix": true,
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"geohash_precision": 6 <1>
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}
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}
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}
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}
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}
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PUT my_index/my_type/1
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{
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"location": {
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"lat": 41.12,
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"lon": -71.34
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}
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}
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GET my_index/_search?fielddata_fields=location.geohash
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{
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"query": {
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"term": {
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"location.geohash": "drm3bt"
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}
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}
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}
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--------------------------------------------------
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// AUTOSENSE
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<1> A `geohash_precision` of 6 equates to geohash cells of approximately 1.26km x 0.6km
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