Обсуждение: Is there a good reason we don't have INTERVAL 'infinity'?
Hackers, Is there a reason why INTERVAL 'infinity' is not implemented? That is, an interval which is larger than all defined intervals, and which added to any timestamp turns it into 'infinity'. Or is it just Round TUITs? -- Josh Berkus PostgreSQL Experts Inc. http://pgexperts.com
<br /><span id="IDstID">Josh Berkus wrote:</span><blockquote cite="mid:4EB095C8.1050703@agliodbs.com" type="cite"><pre wrap="">Hackers, Is there a reason why INTERVAL 'infinity' is not implemented? That is, an interval which is larger than all defined intervals, and which added to any timestamp turns it into 'infinity'. Or is it just Round TUITs?</pre></blockquote><br /> Probably the latter.<br /> There is even a function <tt class="LITERAL"><codeclass="FUNCTION">isfinite(<tt class="TYPE">interval</tt>)</code></tt> which doesn't seem to do anythinguseful.<br /> See complaint in <a class="moz-txt-link-freetext" href="http://archives.postgresql.org/message-id/200101241913.f0OJDUu45423@hub.org">http://archives.postgresql.org/message-id/200101241913.f0OJDUu45423@hub.org</a><br />Although the operation used in this complaint isn't obviously defined there certainly are operations that are defined likeinfinity + infinity = infinity.<br /> See <a class="moz-txt-link-freetext" href="http://de.wikipedia.org/wiki/Unendlichkeit#Analysis">http://de.wikipedia.org/wiki/Unendlichkeit#Analysis</a><br/> (Sorryfor linking the german wikipedia - the english text is ways less verbose on this.)<br /><br /> Regards,<br /><br />Brar<br />
On 2 November 2011 16:35, Brar Piening <brar@gmx.de> wrote: > See http://de.wikipedia.org/wiki/Unendlichkeit#Analysis > (Sorry for linking the german wikipedia - the english text is ways less > verbose on this.) Google Translate has come a very long way. I can read that whole section easily with my brain automatically fixing up the few grammatical errors that Google doesn't get quite right.
Brar Piening wrote: > > Josh Berkus wrote: > > Hackers, > > > > Is there a reason why INTERVAL 'infinity' is not implemented? That is, > > an interval which is larger than all defined intervals, and which added > > to any timestamp turns it into 'infinity'. > > > > Or is it just Round TUITs? > > Probably the latter. > There is even a function |isfinite(interval)| which doesn't seem to do > anything useful. > See complaint in > http://archives.postgresql.org/message-id/200101241913.f0OJDUu45423@hub.org > Although the operation used in this complaint isn't obviously defined > there certainly are operations that are defined like infinity + infinity > = infinity. > See http://de.wikipedia.org/wiki/Unendlichkeit#Analysis > (Sorry for linking the german wikipedia - the english text is ways less > verbose on this.) TODO has: Allow infinite intervals just like infinite timestamps -- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + It's impossible for everything to be true. +