ST_eventType

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Returns the type ID of the event at the specified index in a trajectory object.

Syntax

integer ST_eventType(trajectory traj, integer index)

Parameters

ParameterDescription
trajThe trajectory object.
indexThe event index.

Examples

This example uses a common table expression (CTE) to construct a trajectory object and retrieve the event type ID at index 0.

WITH traj AS (
  SELECT '{"trajectory":{"version":1,"type":"STPOINT","leafcount":2,"start_time":"2010-01-01 11:30:00","end_time":"2010-01-01 12:30:00","spatial":"SRID=4326;LINESTRING(1 1,3 5)","timeline":["2010-01-01 11:30:00","2010-01-01 12:30:00"],"attributes":{"leafcount":2,"velocity":{"type":"integer","length":4,"nullable":true,"value":[1,null]},"speed":{"type":"float","length":8,"nullable":true,"value":[null,1.0]},"angle":{"type":"string","length":64,"nullable":true,"value":["test",null]},"tngel2":{"type":"timestamp","length":8,"nullable":true,"value":["2010-01-01 12:30:00",null]},"bearing":{"type":"bool","length":1,"nullable":true,"value":[null,true]}},"events":[{"1":"Fri Jan 01 14:30:00 2010"},{"2":"Fri Jan 01 14:30:00 2010"}]}}'::trajectory a
)
SELECT ST_eventType(a, 0) FROM traj;

Output:

 st_eventtype
--------------
            1