BUG #15925: Loss of precision converting money to numeric

From: PG Bug reporting form <noreply(at)postgresql(dot)org>
To: pgsql-bugs(at)lists(dot)postgresql(dot)org
Cc: slawomir(dot)chodnicki(at)gmail(dot)com
Subject: BUG #15925: Loss of precision converting money to numeric
Date: 2019-07-26 07:39:17
Message-ID: 15925-da9953e2674bb5c8@postgresql.org
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-bugs

The following bug has been logged on the website:

Bug reference: 15925
Logged by: Slawomir Chodnicki
Email address: slawomir(dot)chodnicki(at)gmail(dot)com
PostgreSQL version: 11.4
Operating system: Linux
Description:

As per documentation converting a money value to numeric does not lose
precision. In general that is the case:

select '8547758.07'::money, '8547758.07'::money::numeric(30,2);

money |numeric |
-------------|----------|
$8,547,758.07|8547758.07|

During my testing I found unexpected results for the min and max value of
the money type.

select '-92233720368547758.08'::money,
'-92233720368547758.08'::money::numeric(30,2);

money |numeric |
---------------------------|---------------------|
-$92,233,720,368,547,758.08|-92233720368547758.00|

Note that the cent value is gone after converting to numeric.

Same issue for the max value:

money |numeric |
--------------------------|--------------------|
$92,233,720,368,547,758.07|92233720368547758.00|

Best Wishes
Slawo

Responses

Browse pgsql-bugs by date

  From Date Subject
Next Message PG Bug reporting form 2019-07-26 13:16:50 BUG #15926: TPCH Q18 slow: explain plan with 2 step Hash Aggregate (partial and finalize)
Previous Message Michael Paquier 2019-07-26 04:58:08 Re: BUG #15827: Unable to connect on Windows using pg_services.conf using Python psycopg2