The type of spatial relationship that must exist between the search envelope and the geometry in the target layer. Any supported relationship, in combination with Result of Spatial Comparison, can be used to filter the features being read.
For example, consider the following settings:
Spatial Relationship to Search Envelope = ST_Intersects
Result of Spatial Comparison = False
This would result in a spatial filter using DB2 Spatial’s native spatial function
DB2GSE.ST_Intersects( g1 geometry, g2 geometry) = 0
where g1 is the search envelope and g2 is the target feature. This will cause FME to return only those features that satisfy the spatial relationship above.
The following table lists the valid spatial relationships.
ST_CONTAINS
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Determines whether the search envelope is completely contained by the target feature.
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ST_CROSSES
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Determines whether the intersection of search envelope and the target feature results in a geometry object whose dimension is one less than the maximum dimension of the source geometries. Also determines if the intersection object contains points that are interior to both source geometries and are not equal to either of the source objects.
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ST_DISJOINT
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Determines whether the intersection of search envelope with the target feature is an empty set.
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ST_EQUALS
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Determines whether the search envelope and target feature are of the same type and have identical x,y coordinate values.
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ST_INTERSECTS
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Determines whether the intersection of search envelope and target feature does not result in an empty set. This is the exact opposite of DISJOINT.
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ST_ORDERINGEQUALS
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Determines whether the search envelope and target feature are equal and the coordinates are in the same order.
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ST_OVERLAPS
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Determines whether the search envelope and target feature overlap each other.
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ST_TOUCHES
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Determines whether any of the points common to search envelope and target feature intersect the interiors of both geometries. At least one geometry must be a linestring, polygon, multilinestring, multipolygon.
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ST_WITHIN
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Determines whether the target feature is completely within the search envelope.
This is exactly opposite to CONTAINS.
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For more details, refer to the IBM DB2 Spatial Extender User’s Guide and Reference.