Spatial Reference Systems (SQL Anywhere)

Sybase IQ v15.4 and higher and SQL Anywhere v12 and higher support spatial reference systems, which define the space in which geometries are described. PowerDesigner models spatial reference systems as extended objects with a stereotype of <<SpatialReferenceSystem>>.

Creating a Spatial Reference System

You can create a spatial reference system in any of the following ways:

  • Select Model > Spatial Reference Systems to access the List of Spatial Reference Systems, and click the Add a Row tool.

  • Right-click the model (or a package) in the Browser, and select New > Spatial Reference System.

Spatial Reference System Properties

You can modify an object's properties from its property sheet. To open a spatial reference system property sheet, double-click its diagram symbol or its Browser entry in the Spatial Reference Systems folder.

The following extended attributes are available on the General tab:

Name

Description

Spatial reference system identifier

Specifies the SRID (srs-id) for the spatial reference system.

Scripting name: SRS_Id

Organization

Specifies the organization that created the spatial reference system that the new spatial reference system is based on.

Scripting name: Organization

Organization coordinate reference system ID

Specifies the numeric identifier the organization uses to identify the spatial reference system.

Scripting name: OrganizationSRSId

The following extended attributes are available on the Definition tab:

Name

Description

Definition

Specifies default coordinate system settings. If any attribute is set in a clause other than the DEFINITION clause, the value specified in the other clause is used regardless of what is specified in the DEFINITION clause.

Scripting name: Definition

Type

Specifies whether the system is Projected, Geographic, or Engineering. If a definition is given, this attribute is computed from the definition text.

Scripting name: SRSType

Transform definition

Specify a description of the transform to use for the spatial reference system.

Scripting name: TransformDefinition

The following extended attributes are available on the Settings tab:

Name

Description

Line interpretation

Specifies how the SRS interprets lines between points.

Scripting name: LineInterpretation

Axis order

Specifies the order in which values are given for each axis.

Scripting name: AxisOrder

Polygon format

Specifies how polygons are interpreted.

Scripting name: PolygonFormat

Storage format

Specifies how data is stored.

Scripting name: StorageFormat

The following extended attributes are available on the Coordinate tab:

Name

Description

Axis/Bounded/Unbounded

Specifies whether the axis is bounded or unbounded and, if it is bounded, the minimum and maximum values.

Scripting names: BoundedCoordinateAxis, MinCoordinateAxis, MaxCoordinateAxis

Ellipsoid axis length

[round earth systems] Specifies the values to use for representing the Earth as an ellipsoid.

Scripting names: SemiMajorAxisLength, SemiMinorAxisLength, InverseFlattening

Grid Size

[planar systems] Specifies the size of the grid to use when performing calculations.

Scripting name: GridSize

Tolerance

[planar systems] Specifies the precision to use when comparing points.

Scripting name: Tolerance

Linear/Angular unit of measure

Specify the linear and angular units of measure for the spatial reference system.

Scripting name: LinearUnitOfMeasure, AngularUnitOfMeasure