Re: [HACKERS] pow support for pgbench - Mailing list pgsql-hackers

From Fabien COELHO
Subject Re: [HACKERS] pow support for pgbench
Date
Msg-id alpine.DEB.2.20.1712051355450.7660@lancre
Whole thread Raw
In response to Re: [HACKERS] pow support for pgbench  (Raúl Marín Rodríguez <rmrodriguez@carto.com>)
List pgsql-hackers
> I've been giving a thought about this and I think we could reach the
> compromise
> of having a single function with 2 overloads:
> * pow(double, double) -> double: Uses C pow().
> * pow(int, int) -> double: Uses ipow() for positive exponents, and pow()
> for negative exponents.
>
> In both cases we'd return a double but we use the fast ipow if it's 
> possible (which can be 20x faster), so at the cost of an extra cast if 
> you need an int, we'd have a consistent API. Would this be acceptable?

This is for Robert to say whether it is more acceptable to him.

My 0.02€: ISTM that it closely equivalent to having just the double 
version and using an explicit cast to get an int if needed, which does not 
conform anymore to strict SQL behavior than the previous compromise.

Also, probably having something (anything) is better than nothing.

-- 
Fabien.

pgsql-hackers by date:

Previous
From: Raúl Marín Rodríguez
Date:
Subject: Re: [HACKERS] pow support for pgbench
Next
From: Rafia Sabih
Date:
Subject: Re: [HACKERS] [POC] Faster processing at Gather node