This topic describes the spatio-temporal functions supported by Lindorm GanosBase.
Applicable engines and versions
The spatio-temporal functions described in this topic are applicable only to all versions of LindormTable.
Functions
The following table lists the spatio-temporal functions supported by Lindorm GanosBase.
The names of the spatio-temporal functions are case-insensitive.
Category | Documentation | Description |
Constructor functions | Constructs a geometry object based on the specified Well-known Text (WKT) string. | |
Constructs a LineString object based on the specified MultiPoint object. | ||
Constructs a point object. | ||
Output functions | Returns the information about a geometry object in Well-known Text (WKT) format. | |
Access functions | Returns the centroid of the specified geometry object. | |
Returns the last point of the specified LineString object. | ||
Returns the number of vertexes in the specified geometry object. | ||
Returns the start point of the specified LineString object. | ||
Returns the x coordinate of the specified point object. | ||
Returns the maximum x coordinate on the bounding box of the specified geometry object. | ||
Returns the minimum x coordinate on the bounding box of the specified geometry object. | ||
Returns the y coordinate of the specified point object. | ||
Returns the maximum y coordinate on the bounding box of the specified geometry object. | ||
Returns the minimum y coordinate on the bounding box of the specified geometry object. | ||
Functions for spatial relationships | Checks whether the first geometry object that you specify contains the second geometry object that you specify. If the first geometry object contains the second geometry object, this function returns true. | |
Checks whether the 2D distance between two geometry objects is within the specified range. If the 2D distance between the objects is within the specified range, this function returns true. | ||
Checks whether the spherical distance between two geometry objects is within the specified range. If the spherical distance between the objects is within the specified range, this function returns true. | ||
Checks whether two geometry objects intersect. If the two geometry objects have any shared spatial space, this function determines that the two objects intersect and returns true. | ||
Checks whether two geometry objects spatially overlap but one is not included in the other. If the two geometry objects spatially overlap but one is not included in the other, this function returns true. | ||
Checks whether the second geometry object that you specify completely lies in the first geometry object that you specify. If the second geometry object completely lies in the first geometry object, this function returns true. | ||
Aggregate functions | Returns the spherical length of the trajectory aggregated by all points in the specified point column. The unit of the returned value is meter. This function reads all points in the specified point column in the order of the primary keys, and then calculates the length of the trajectory aggregated by the points. | |
Calculates the trajectory aggregated by all points in the specified point column based on the order of time data in the specified time column, and returns the trajectory segments divided by a specific time threshold. This function is usually used together with functions for spatial relationship, such as ST_DWithinSphere. In this case, you can calculate the coordinates and time of the point that first enters a specified area and the point that last leaves a specified area in a trajectory segment. | ||
Generates a trajectory by using the specified time points that are sorted in ascending order and downsampled based on the specified threshold. |