From: Tom Lane <tgl@sss.pgh.pa.us>
To: Erki Eessaar <erki.eessaar@taltech.ee>
cc: "pgsql-bugs@lists.postgresql.org" <pgsql-bugs@lists.postgresql.org>
Subject: Re: Problem with Avg function and Money type in PostgreSQL 15
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Comments: In-reply-to Erki Eessaar <erki.eessaar@taltech.ee>
	message dated "Sun, 30 Oct 2022 10:15:32 -0000"
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Date: Sun, 30 Oct 2022 13:57:37 -0400
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Erki Eessaar <erki.eessaar@taltech.ee> writes:
> CREATE TABLE Product(product_id SERIAL PRIMARY KEY,
> price MONEY NOT NULL);

> INSERT INTO Product(price) VALUES (30);
> INSERT INTO Product(price) VALUES (40);

> SELECT Avg(price) AS av FROM Product;

> PostgreSQL 15

> ERROR:  stack depth limit exceeded
> HINT:  Increase the configuration parameter "max_stack_depth" (currently=
 2048kB), after ensuring the platform's stack depth limit is adequate.
> CONTEXT:  SQL function "avg" during inlining


I get "function avg(money) does not exist" in all branches.
Judging from the mention of a SQL function, you must have
created a not-very-well-thought-out SQL function named "avg",
and that function is recursing till stack overflow.

			regards, tom lane