Index Properties (Spatial Page)

When you are creating a spatial index, use the Spatial page of the New Index dialog box to specify the values of the spatial properties.

For an existing spatial index, use the Spatial page of the Index Properties dialog box to view or modify the spatial properties of the index. When you modify any of the spatial properties, the spatial index is dropped and re-created.

Note

When you are creating a spatial index, you can generate the Transact-SQL CREATE SPATIAL INDEX script for creating the spatial index by clicking the Script button and then selecting a destination for the script.

To create a spatial index in SQL Server Management Studio

To view the properties of an index in SQL Server Management Studio

Options

Bounding Box

The bounding box is the perimeter of the top-level grid of a geometric plane. The bounding-box parameters exist only in the geometry grid tessellation. These parameters are dimmed if the Tessellation Scheme is Geography grid.

The panel displays the (X-min,Y-min) and (X-max,Y-max) coordinates of the bounding box. There are no default coordinate values. Therefore, when you are creating a new spatial index on a geometry type column, you must specify the coordinate values.

  • X-min
    The X-coordinate of the lower-left corner of the bounding box.

  • Y-min
    The Y-coordinate of the lower-left corner of the bounding box.

  • X-max
    The X-coordinate of the upper-right corner of the bounding box.

  • Y-max
    The Y-coordinate of upper-right corner of the bounding box.

General

  • Tessellation Scheme
    Indicates the tessellation scheme of the index. The supported tessellation schemes are:

    • Geometry grid
      Specifies the geometry grid tessellation scheme, which applies to a column of the geometry data type.

    • Geography grid
      Specifies the geography grid tessellation scheme, which applies to a column of the geography data type.

    For information about how SQL Server implements tessellation, see Spatial Indexing Overview.

  • Cells Per Object
    Indicates the number of tessellation cells-per-object that can be used for a single spatial object in the index. This number can be any integer between 1 and 8192, inclusive. The default is 16.

    At the top level, if an object covers more cells than specified by n, the indexing uses as many cells as necessary to provide a complete top-level tessellation. In such cases, an object might receive more than the specified number of cells. In this case, the maximum number is the number of cells generated by the top-level grid, which depends on the Level 1 density.

Grids

This panel shows the density of the grid at each level of the tessellation scheme. Density is specified as Low, Medium, or High. The default is Medium. Low represents a 4x4 grid (16 cells), Medium represents an 8x8 grid (64 cells), and High represents a 16x16 grid (256 cells).

  • Level 1
    The density of the first-level (top) grid.

  • Level 2
    The density of the second-level grid.

  • Level 3
    The density of the third-level grid.

  • Level 4
    The density of the fourth-level grid.