Geospatial Operators

Bing Tile Functions

Bing tiles are a convenient quad-tree representation of the WGS84 projection of Earth’s surface. They can be used to partition geospatial data, perform quick proximity or intersection checks, and more. Each tile is defined by a zoom level (how far down the quad-tree the tile lives), and an x and y coordinate specifying where it is in that zoom level. Velox supports zoom levels from 0 to 23. For a given zoom level, x and y must be between 0 and 2**zoom - 1 inclusive. Lower x values are west of higher x values, and lower y values are north of higher y values.

Bing tiles can be cast to and from an efficient BIGINT representation. While every Bing tile can be cast to a valid BIGINT, not every BIGINT is a valid Bing tile, so casting BIGINT to BINGTILE may fail.

::

CAST(CAST(tile AS BIGINT) AS BINGTILE)

See https://learn.microsoft.com/en-us/bingmaps/articles/bing-maps-tile-system for more details.

bing_tile(x: integer, y: integer, zoom_level: tinyint) → tile: BingTile

Creates a Bing tile object from x, y coordinates and a zoom_level. Zoom levels from 0 to 23 are supported, with valid x and y coordinates described above. Invalid parameters will return a User Error.

bing_tile_coordinates(tile: BingTile) -> coords: row(integer, integer)

Returns the x, y coordinates of a given Bing tile as row(x, y).

bing_tile_zoom_level(tile: BingTile) → zoom_level: tinyint

Returns the zoom level of a given Bing tile.

bing_tile_parent(tile) → parent: BingTile

Returns the parent of the Bing tile at one lower zoom level. Throws an exception if tile is at zoom level 0.

bing_tile_parent(tile, parentZoom) → parent: BingTile

Returns the parent of the Bing tile at the specified lower zoom level. Throws an exception if parentZoom is less than 0, or parentZoom is greater than the tile’s zoom.

bing_tile_children(tile) -> children: array(BingTile)

Returns the children of the Bing tile at one higher zoom level. Throws an exception if tile is at max zoom level.

bing_tile_children(tile, childZoom) -> children: array(BingTile)

Returns the children of the Bing tile at the specified higher zoom level. Throws an exception if childZoom is greater than the max zoom level, or childZoom is less than the tile’s zoom. The order is deterministic but not specified.