sql

lib/sql/doc/CartoDB-PLpgSQL.md

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+INTRODUCTION
+============
+
+CartoDB uses a number of custom [PLpgSQL](http://www.postgresql.org/docs/8.3/static/plpgsql.html) 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](CDB_HexagonGrid) - create hexagonal grid from extent and size
+
+[CDB_MakeHexagon](CDB_MakeHexagon) - make a hexagon with given center and side
+
+[CDB_RectangleGrid](CDB_RectangleGrid) - fill given extent with a rectangular coverage
+
+##### Tile based
+
+[CDB_XYZ_Extent](CDB_XYZ_Extent) - Find the extent of a tile by XYZ
+
+[CDB_XYZ_Resolution](CDB_XYZ_Resolution) - Find the pixel resolution of tiles
+
+[CDB_TransformToWebmercator](CDB_TransformToWebmercator) - Convert a geometry to valid webmercator
+
+## Statistical functions
+
+[CDB_JenksBins](CDB_JenksBins) - Find breaks in an array of numbers using Jenks method
+
+[CDB_HeadsTailsBins](CDB_HeadsTailsBins) - Find breaks in an array of numbers using Heads/Tails method
+
+[CDB_QuantileBins](CDB_QuantileBins) - Find quantile breaks in an array of numbers
+
+## System functions
+
+[CDB_UserTables](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