...
Now we can use this index to run a continuous range query for the vessels. We could reduce the number of vessels where we do the range query for by using another "Select"-operator. Nevertheless, here we calculate the range for every incoming object. The result of the query is within the "neighbors"-field of the tuple and as for now contains a JSON-object.
| Code Block |
|---|
#PARSER PQL
#DEFINE dataStructureName 'sanFranciscoStore'
#ADDQUERY
/// For every vessel we want to know which vessels are near them all the time
range = MOVINGOBJECTRANGE({
geometryattribute = 'SpatialPoint',
datastructurename = ${dataStructureName},
range = 300
},
System.SanFranciscoAIS
) |
A result could look like this:
| Code Block |
|---|
12|UnderwayUsingEngine|NotAvailable|223|false|218.2|12.9|374128000|20|false|POINT (37.751635 -122.68389166666667)|{"374128000":[{"trajectoryElement":{"movingObjectID":"374128000","geoHash":{"bits":5589500436528045806,"point":{"longitude":-122.68389166666667,"latitude":37.751635},"boundingBox":{"minLat":37.75163498707116,"maxLat":37.75163502898067,"minLon":-122.68389173783362,"maxLon":-122.68389165401459},"significantBits":64},"distanceToPreviousElement":66.39223462250055,"streamElement":{}},"meters":0.0},{"trajectoryElement":{"movingObjectID":"374128000","geoHash":{"bits":5589500440284126512,"point":{"longitude":-122.682585,"latitude":37.75300333333333},"boundingBox":{"minLat":37.75300333276391,"maxLat":37.753003374673426,"minLon":-122.68258508294821,"maxLon":-122.68258499912918},"significantBits":64},"distanceToPreviousElement":64.17029786044263,"streamElement":{}},"meters":190.5932328122322},{"trajectoryElement":{"movingObjectID":"374128000","geoHash":{"bits":5589500441130161997,"point":{"longitude":-122.68214666666667,"latitude":37.753465},"boundingBox":{"minLat":37.75346496608108,"maxLat":37.7534650079906,"minLon":-122.68214670941234,"maxLon":-122.6821466255933},"significantBits":64},"distanceToPreviousElement":63.10852580037621,"streamElement":{}},"meters":254.76334501265032},{"trajectoryElement":{"movingObjectID":"374128000","geoHash":{"bits":5589500439526094378,"point":{"longitude":-122.68342833333334,"latitude":37.75210666666667},"boundingBox":{"minLat":37.75210663676262,"maxLat":37.752106678672135,"minLon":-122.6834283862263,"maxLon":-122.68342830240726},"significantBits":64},"distanceToPreviousElement":59.35999960990177,"streamElement":{}},"meters":66.39223462250055},{"trajectoryElement":{"movingObjectID":"374128000","geoHash":{"bits":5589500439809071195,"point":{"longitude":-122.683025,"latitude":37.752535},"boundingBox":{"minLat":37.7525349939242,"maxLat":37.752535035833716,"minLon":-122.68302504904568,"maxLon":-122.68302496522665},"significantBits":64},"distanceToPreviousElement":64.85054572839009,"streamElement":{}},"meters":125.74570287102185}]} | META | 1488546619406|oo |
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Future Work
...