This tab has the following components:
Spatial reference system type Specifies the type of spatial reference system, as defined by the SQL/MM standard. Values can be Geographic, Projected, or Engineering (internal use). See srs_type.
Line interpretation Specifies how the spatial reference system interprets lines between points. When the Spatial Reference System Type is Geographic you can select either Round earth or Planar. Otherwise, you can only select Planar. See TYPE clause, CREATE SPATIAL REFERENCE SYSTEM statement.
Round earth Select to have the earth represented using an ellipsoid, providing a two-dimensional representation of a three-dimensional model of the Earth.
Planar Select to have the Earth represented on a flat, two-dimensional plane.
Axis order Specifies how the database server interprets points with regards to latitude and longitude. When the Spatial Reference System Type is Geographic, the default axis order is Long./Lat./Z/M; Lat./Long./Z/M is also supported. When the Spatial Reference System Type is Projected or Engineering, the axis order is X/Y/Z/M.
Polygon format Specifies how the database should interpret polygons. Internally, SQL Anywhere formats its polygons counterclockwise; however other products can format their polygons differently. See POLYGON FORMAT clause, CREATE SPATIAL REFERENCE SYSTEM statement.
The following is a list of polygon formats that SQL Anywhere supports:
Counterclockwise The inside of the polygon is on the left side while following ring orientation.
Clockwise The inside of the polygon is on the right hand side while following ring orientation.
EvenOdd The orientation of rings is ignored and the inside of the polygon is instead determined by looking at the nesting of the rings, with the exterior ring being the largest ring and interior rings being smaller rings inside this ring. A ray is traced from a point within all rings, radiating outward. This is the default format.
Storage format Specifies the format that is used to store the spatial data. See STORAGE FORMAT clause, CREATE SPATIAL REFERENCE SYSTEM statement.
Internal SQL Anywhere stores only the normalized representation. This is the default option when the Line Interpretation is Planar.
Original SQL Anywhere stores only the original representation. The original input characteristics can be reproduced, but all operations on the stored values must repeat normalization steps, possibly slowing down the operations.
Mixed SQL Anywhere stores both the original and internal representations, if different. The original representation characteristics can be reproduced and operations on stored values do not need to repeat normalization steps. This is the default option when the Line Interpretation is Round Earth.
Semi-major axis Specifies the distance from center of the earth to the equator. See ELLIPSOID clause, CREATE SPATIAL REFERENCE SYSTEM statement.
Inverse flattening Specifies the inverse flattening ratio. See ELLIPSOID clause, CREATE SPATIAL REFERENCE SYSTEM statement.
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