Postgresql tree data structure

问题

I have installed Postgresql 9.2 and would like to use LTREE data type. When I try to create table as in the documentation.

CREATE TABLE test (path ltree);

I have error: type ltree does not exist
I use pgAdmin III for this query. What am I doing wrong? Should I install this module separately. If yes, how?
P.S. OS Windows.

回答1:

You need to install the ltree extension by running:

CREATE EXTENSION ltree;

as a superuser.

See the manual for details: http://www.postgresql.org/docs/current/static/sql-createextension.html

You might also want to read up on recursive queries which let query this kind of data structure in a "regular table" using a parent_id

来源：https://stackoverflow.com/questions/17065625/postgresql-tree-data-structure