Feature Representation

Features read from Informix Spatial consist of a series of attribute values and geometry. The feature type of each Database feature is as defined on its DEF line.

Features written to the database have the destination table as their feature type, and attributes as defined by on the DEF line.

In addition to the generic FME feature attributes that FME Workbench adds to all features (see About Feature Attributes), the Informix Spatial module adds the format-specific attributes described below:

Attribute Name

Contents

infx_type

The type of geometric entity stored within the feature. The valid values for the object model are listed below:

infx_null

infx_point

infx_linestring

infx_polygon

infx_geometry

Features read from, or written to, Informix Spatial also have an attribute for each column in the database table. The feature attribute name will be the same as the source or destination column name. The attribute and column names are not case-sensitive.

No Coordinates

infx_type: infx_null

Features with no coordinates are tagged with this value when reading from or writing to Informix Spatial.

Points

infx_type: infx_point

All Informix Spatial point and multipoint features are read as infx_point. The only difference being the geometry type of feature, which will be set to fme_aggregate if it is a multipoint and fme_point if it is a point.

Lines

infx_type: infx_line

All Informix Spatial linestring and multilinestring features are read as infx_line. The only difference is the geometry type of feature, which will be set to fme_aggregate if it is a multilinestring and fme_line if it is a linestring.

Polygons

infx_type: infx_polygon

All Informix Spatial polygon and multipolygon features are read as infx_polygon. The only difference is the geometry type of feature, which will be set to fme_aggregate if it is a multipolygon and fme_polygon if it is a polygon. Polygon features include donut polygons with one or more holes.

The following table summarizes all of the infx_type values that are possible with Informix Spatial geometry, and provides a description of each representation.

infx_type

Informix Spatial type

Representation

infx_null

Not applicable

No geometry

infx_point

POINT

Single point geometry.

fme_geometry = fme_point

fme_type = fme_point

MULTIPOINT

Aggregate containing one or more points.

fme_geometry = fme_aggregate

fme_type = fme_point

infx_line

LINESTRING

Single line geometry.

fme_geometry = fme_line

fme_type = fme_line

MULTILINESTRING

An aggregate of linestrings.

fme_geometry = fme_aggregate

fme_type = fme_line

infx_polygon

POLYGON

A single polygon or donut geometry.

fme_geometry = fme_polygon or fme_donut

fme_type = fme_polygon

 

MULTIPOLYGON

An aggregate of simple polygons or donut polygons.

fme_geometry = fme_aggregate

fme_type = fme_polygon

infx_geometry

GEOMETRY

An arbitrary geometry.