如何启用 hstore_plpython3u

Question

扩展 hstore_plpython3u 应该按照文档中的描述转换 hstore to/from python dict，但似乎不起作用。 hstore 变成了一个字符串（似乎没有发生转换）。为什么，以及如何解决它？

The extensions for PL/Python are called hstore_plpythonu, hstore_plpython2u, and hstore_plpython3u (see Section 45.1 for the PL/Python naming convention). If you use them, hstore values are mapped to Python dictionaries. https://www.postgresql.org/docs/current/hstore.html

创建扩展

create extension plpython3u;
create extension hstore_plpython3u;

创建函数

create function type(names hstore)
returns text
language plpython3u as $$
   return type(names);
$$;

调用函数

select type(hstore('name','martin'));

returns

     type      
---------------
 <class 'str'>
(1 row)

Answer 1

我想明白了。来自 /contrib/hstore_plpython 中的 expected/hstore_plpython.out 文件：

CREATE FUNCTION test1arr(val hstore[]) RETURNS int
LANGUAGE plpythonu
TRANSFORM FOR TYPE hstore
AS $$
assert(val == [{'aa': 'bb', 'cc': None}, {'dd': 'ee'}])
return len(val)
$$;
SELECT test1arr(array['aa=>bb, cc=>NULL'::hstore, 'dd=>ee']);
 test1arr
----------
        2

如何启用 hstore_plpython3u

How to enable hstore_plpython3u

postgresql

hstore

plpython