cartodb-postgresql/doc/CartoDB-PLpgSQL.md
2015-07-01 07:01:50 -07:00

1.4 KiB

INTRODUCTION

CartoDB uses a number of custom PLpgSQL functions to perform a few magical things. Those functions are accessible to users on CartoDB as well, so we would like to document what they are and what they do here.

Spatial functions

CDB_HexagonGrid - create hexagonal grid from extent and size

CDB_MakeHexagon - make a hexagon with given center and side

CDB_RectangleGrid - fill given extent with a rectangular coverage

Tile based

CDB_XYZ_Extent - Find the extent of a tile by XYZ

CDB_XYZ_Resolution - Find the pixel resolution of tiles

CDB_TransformToWebmercator - Convert a geometry to valid webmercator

Statistical functions

CDB_JenksBins - Find breaks in an array of numbers using Jenks method

CDB_HeadsTailsBins - Find breaks in an array of numbers using Heads/Tails method

CDB_QuantileBins - Find quantile breaks in an array of numbers

System functions

CDB_UserTables - Get a list of all tables in your account

CDB_SetUserQuotaInBytes - Set maximum user quota in bytes

column names - now returned in JSON response

column types - now returned in JSON response