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The OpenGIS Specification for Simple Features in SQL defines a binary geometry schema as one of three schemas for managing spatial data. In the
binary geometry
schema, the coordinate values for the shape are stored in a binary object called a BLOB. The BLOB is managed in a separate
geometry table. Access to the geometry
from the business table is through a foreign key—the Geometry ID, or GID.
The relationship between the business table and the geometry table in the binary geometry schema:
The ArcSDE binary schema is the same geometry storage schema used in earlier ArcSDE releases. This schema implements the OpenGIS Binary schema, with additional
functionality, and a compressed binary representation in place of the OpenGIS Well-Known Binary Representation for Geometry. The compressed binary representation
provides support for geometry properties not defined by the OpenGIS specification, including:
elevations, measures, annotation, and CAD data. Functions are available
in the C, JAVA, and SQL type API to convert this compressed binary representation into OpenGIS Well-Known Binary and Well-Known Text representations of
geometry.
The internal format of the ArcSDE binary is defined in ArcSDE compressed binary representation.
The schema for the ArcSDE binary schema geometry table is as follows:
| fid |
INTEGER |
NOT NULL |
The ID of the geometry |
| numofpts |
INTEGER |
NOT NULL |
The number of coordinate values in the
geometry |
| entity |
SMALLINT |
NOT NULL |
An accumulated mask of geometry and
coordinate type flags. |
| eminx
|
FLOAT(64) |
NOT NULL |
Minimum x ordinate value |
| eminy
|
Minimum y ordinate value |
| emaxx |
Maximum x ordinate value |
| emaxy |
Maximum y ordinate value |
| eminz |
Minimum
z ordinate value
(Initializes to NULL). |
| emaxz |
Maximum z ordinate value
(Initializes to NULL) |
| min_measure |
FLOAT(64) |
NOT NULL |
Minimum m ordinate value
(Initializes to NULL) |
| max_measure |
Maximum m ordinate value
(Initializes to NULL) |
| area |
FLOAT(64) |
NOT NULL |
Calculated area for the geometry |
| len |
FLOAT(64) |
NOT NULL |
Calculated length or perimeter for the
geometry |
| points |
<BLOB
DATATYPE> |
NOT NULL |
Geometry coordinate values |
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