Can't use ltree data type in postgresql

Question

According to https://dzone.com/articles/installing-the-postgres-ltree-extension, ltree is installed and enabled on my computer. But when I try to make a table with a column of type ltree in Postbird, it says 'type "ltree" does not exist'. This makes no sense. Please help.

Answer 1

Only execute this command in psql or some postgresql's sql client:

CREATE EXTENSION ltree;