Our S2 module is based on a port of the official S2 geometry library created by Google. For more information about S2 check the library's website or the Spatial Indexes section of this documentation.
S2_BOUNDARY
Description
Returns the boundary for a given S2 cell ID. We extract the boundary by getting the corner longitudes and latitudes, then enclose it in a GeoJSON and finally transform it into geography.
id: INT64 S2 cell ID to get the boundary geography from.
Return type
GEOGRAPHY
Example
carto-un carto-un-eu manual
Copy SELECT `carto-un`.carto.S2_BOUNDARY(955378847514099712);
-- POLYGON((-3.41955272426037 40.25850071217, -3.41955272426037 ...
Copy SELECT `carto-un-eu`.carto.S2_BOUNDARY(955378847514099712);
-- POLYGON((-3.41955272426037 40.25850071217, -3.41955272426037 ...
Copy SELECT carto.S2_BOUNDARY(955378847514099712);
-- POLYGON((-3.41955272426037 40.25850071217, -3.41955272426037 ...
S2 Cell edges are spherical geodesics. The boundary edges can be interpreted as straight lines in other GIS tools, so to export the exact shape of the cells, use ST_GEOGFROM(ST_ASGEOJSON(geog). In this process, BigQuery will add intermediate points to preserve the geodesic curves.
S2_CENTER
Description
Returns a POINT corresponding to the centroid of an S2 cell, given its ID.
id: INT64 S2 cell ID to get the boundary geography from.
Return type
GEOGRAPHY
Example
carto-un carto-un-eu manual
Copy SELECT `carto-un`.carto.S2_CENTER(955378847514099712);
-- POINT(-3.58126923539589 40.4167087628243)
Copy SELECT `carto-un-eu`.carto.S2_CENTER(955378847514099712);
-- POINT(-3.58126923539589 40.4167087628243)
Copy SELECT carto.S2_CENTER(955378847514099712);
-- POINT(-3.58126923539589 40.4167087628243) S2_FROMGEOGPOINT
Copy S2_FROMGEOGPOINT(point, resolution) Description
Returns the S2 cell ID of a given point at a requested resolution.
point: GEOGRAPHY point to get the ID from.
resolution: INT64 level of detail or zoom.
Return type
INT64
Example
carto-un carto-un-eu manual
Copy SELECT `carto-un`.carto.S2_FROMGEOGPOINT(ST_GEOGPOINT(-3.7038, 40.4168), 8);
-- 955378847514099712
Copy SELECT `carto-un-eu`.carto.S2_FROMGEOGPOINT(ST_GEOGPOINT(-3.7038, 40.4168), 8);
-- 955378847514099712
Copy SELECT carto.S2_FROMGEOGPOINT(ST_GEOGPOINT(-3.7038, 40.4168), 8);
-- 955378847514099712 S2_FROMHILBERTQUADKEY
Copy S2_FROMHILBERTQUADKEY(hquadkey) Description
Returns the conversion of a Hilbert quadkey (a.k.a Hilbert curve quadtree ID) into a S2 cell ID.
hquadkey: STRING Hilbert quadkey to be converted.
Return type
INT64
Example
carto-un carto-un-eu manual
Copy SELECT `carto-un`.carto.S2_FROMHILBERTQUADKEY('0/12220101');
-- 955378847514099712
Copy SELECT `carto-un-eu`.carto.S2_FROMHILBERTQUADKEY('0/12220101');
-- 955378847514099712
Copy SELECT carto.S2_FROMHILBERTQUADKEY('0/12220101');
-- 955378847514099712 S2_FROMLONGLAT
Copy S2_FROMLONGLAT(longitude, latitude, resolution) Description
Returns the S2 cell ID for a given longitude, latitude and zoom resolution.
longitude: FLOAT64 horizontal coordinate on the map.
latitude: FLOAT64 vertical coordinate on the map.
resolution: INT64 level of detail or zoom.
Return type
INT64
Example
carto-un carto-un-eu manual
Copy SELECT `carto-un`.carto.S2_FROMLONGLAT(-3.7038, 40.4168, 8);
-- 955378847514099712
Copy SELECT `carto-un-eu`.carto.S2_FROMLONGLAT(-3.7038, 40.4168, 8);
-- 955378847514099712
Copy SELECT carto.S2_FROMLONGLAT(-3.7038, 40.4168, 8);
-- 955378847514099712 S2_FROMTOKEN
Description
Returns the conversion of a token into a S2 cell ID.
token: STRING S2 cell hexified ID.
Return type
INT64
Example
carto-un carto-un-eu manual
Copy SELECT `carto-un`.carto.S2_FROMTOKEN('0d42300000000000');
-- 955378847514099712
Copy SELECT `carto-un-eu`.carto.S2_FROMTOKEN('0d42300000000000');
-- 955378847514099712
Copy SELECT carto.S2_FROMTOKEN('0d42300000000000');
-- 955378847514099712 S2_FROMUINT64REPR
Copy S2_FROMUINT64REPR(uid) Description
Returns the cell ID from a UINT64 representation.
uid: STRING UINT64 representation of a S2 cell ID.
Return type
INT64
Example
carto-un carto-un-eu manual
Copy SELECT `carto-un`.carto.S2_FROMUINT64REPR('9926595690882924544');
-- -8520148382826627072
Copy SELECT `carto-un-eu`.carto.S2_FROMUINT64REPR('9926595690882924544');
-- -8520148382826627072
Copy SELECT carto.S2_FROMUINT64REPR('9926595690882924544');
-- -8520148382826627072 S2_RESOLUTION
Description
Returns the S2 cell resolution as an integer.
index: STRING The S2 cell index.
Return type
INT64
Example
carto-un carto-un-eu manual
Copy SELECT `carto-un`.carto.S2_RESOLUTION(955378847514099712);
-- 9
Copy SELECT `carto-un-eu`.carto.S2_RESOLUTION(955378847514099712);
-- 9
Copy SELECT carto.S2_RESOLUTION(955378847514099712);
-- 9 S2_TOCHILDREN
Copy S2_TOCHILDREN(index, resolution) Description
Returns an array with the S2 indexes of the children/descendents of the given hexagon at the given resolution.
index: STRING The S2 cell index.
resolution: INT64 number between 0 and 30 with the S2 resolution .
Return type
ARRAY<STRING>
Example
carto-un carto-un-eu manual
Copy SELECT `carto-un`.carto.S2_TOCHILDREN(955378847514099712, 10);
-- 955365653374566400
-- 955374449467588608
-- 955383245560610816
-- 955392041653633024
Copy SELECT `carto-un-eu`.carto.S2_TOCHILDREN(955378847514099712, 10);
-- 955365653374566400
-- 955374449467588608
-- 955383245560610816
-- 955392041653633024
Copy SELECT carto.S2_TOCHILDREN(955378847514099712, 10);
-- 955365653374566400
-- 955374449467588608
-- 955383245560610816
-- 955392041653633024 S2_TOHILBERTQUADKEY
Copy S2_TOHILBERTQUADKEY(id) Description
Returns the conversion of a S2 cell ID into a Hilbert quadkey (a.k.a Hilbert curve quadtree ID).
id: INT64 S2 cell ID to be converted.
Return type
STRING
Example
carto-un carto-un-eu manual
Copy SELECT `carto-un`.carto.S2_TOHILBERTQUADKEY(955378847514099712);
-- 0/12220101
Copy SELECT `carto-un-eu`.carto.S2_TOHILBERTQUADKEY(955378847514099712);
-- 0/12220101
Copy SELECT carto.S2_TOHILBERTQUADKEY(955378847514099712);
-- 0/12220101 S2_TOTOKEN
Description
Returns the conversion of a S2 cell ID into a token (S2 cell hexified ID).
Return type
STRING
Example
carto-un carto-un-eu manual
Copy SELECT `carto-un`.carto.S2_TOTOKEN(955378847514099712);
-- 0d42300000000000
Copy SELECT `carto-un-eu`.carto.S2_TOTOKEN(955378847514099712);
-- 0d42300000000000
Copy SELECT carto.S2_TOTOKEN(955378847514099712);
-- 0d42300000000000 S2_TOUINT64REPR
Description
Returns the UINT64 representation of a cell ID.
Return type
STRING
Example
carto-un carto-un-eu manual
Copy SELECT `carto-un`.carto.S2_TOUINT64REPR(-8520148382826627072);
-- 9926595690882924544
Copy SELECT `carto-un-eu`.carto.S2_TOUINT64REPR(-8520148382826627072);
-- 9926595690882924544
Copy SELECT carto.S2_TOUINT64REPR(-8520148382826627072);
-- 9926595690882924544 Last updated 4 months ago
