ltree
The ltree module implements a data type named ltree that you can use to represent labels of data stored in a hierarchical tree-like structure. The module also provides extensive facilities for searching through label trees.
The Greenplum Database ltree module is based on the ltree module used with PostgreSQL. The Greenplum version of the module differs as described in the See: Greenplum Database Considerations topic.
Installing and Registering the Module
The ltree module is installed when you install Greenplum Database. Before you can use any of the data types, functions, or operators defined in the module, you must register the ltree extension in each database in which you want to use the objects:
Refer to Installing Additional Supplied Modules for more information.
Module Documentation
Refer to the ltree PostgreSQL documentation for detailed information about the data types, functions, and operators defined in this module.
Greenplum Database Considerations
Because this extension does not provide a hash operator class, columns defined with the data type ltree can not be used as the distribution key for a Greenplum Database table.