Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1XSQb6-0000qk-SU for pgsql-docs@arkaria.postgresql.org; Fri, 12 Sep 2014 13:09:08 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1XSQb6-00013Q-85 for pgsql-docs@arkaria.postgresql.org; Fri, 12 Sep 2014 13:09:08 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1XSQb5-00013I-C8 for pgsql-docs@postgresql.org; Fri, 12 Sep 2014 13:09:07 +0000 Received: from bay004-omc3s24.hotmail.com ([65.54.190.162]) by magus.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1XSQaw-0005zC-4i for pgsql-docs@postgresql.org; Fri, 12 Sep 2014 13:09:06 +0000 Received: from BAY175-W1 ([65.54.190.187]) by BAY004-OMC3S24.hotmail.com with Microsoft SMTPSVC(7.5.7601.22724); Fri, 12 Sep 2014 06:08:54 -0700 X-TMN: [MGuaCAqoOiZf649nX9fQSV8G162oTyfG] X-Originating-Email: [johnlumby@hotmail.com] Message-ID: From: John Lumby To: David Johnston CC: postgresql docmaillist Subject: Re: NULL as a (pseudo-)value not described? Date: Fri, 12 Sep 2014 09:08:53 -0400 Importance: Normal In-Reply-To: References: , <1410398400332-5818543.post@n5.nabble.com>, , , , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 MIME-Version: 1.0 X-OriginalArrivalTime: 12 Sep 2014 13:08:54.0561 (UTC) FILETIME=[B4781110:01CFCE8A] X-Pg-Spam-Score: -3.1 (---) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-docs Precedence: bulk Sender: pgsql-docs-owner@postgresql.org CgpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fXwo+IERhdGU6IFRo dSwgMTEgU2VwIDIwMTQgMjI6MDg6MDUgLTA0MDAgCj4gU3ViamVjdDogUmU6 IFtET0NTXSBOVUxMIGFzIGEgKHBzZXVkby0pdmFsdWUgbm90IGRlc2NyaWJl ZD8gCj4gRnJvbTogZGF2aWQuZy5qb2huc3RvbkBnbWFpbC5jb20gCj4gVG86 IGpvaG5sdW1ieUBob3RtYWlsLmNvbSAKPiBDQzogcGdzcWwtZG9jc0Bwb3N0 Z3Jlc3FsLm9yZyAKPiAgCj4gIAo+ICAKPiBPbiBUaHUsIFNlcCAxMSwgMjAx NCBhdCA5OjI0IFBNLCBqb2hubHVtYnkgIAo+IDxqb2hubHVtYnlAaG90bWFp bC5jb208bWFpbHRvOmpvaG5sdW1ieUBob3RtYWlsLmNvbT4+IHdyb3RlOiAK PiBPbiAwOS8xMS8xNCAxMDowMywgRGF2aWQgSm9obnN0b24gd3JvdGU6IAo+ IE9uIFRodSwgU2VwIDExLCAyMDE0IGF0IDk6MjQgQU0sIEpvaG4gTHVtYnkg IAo+IDxqb2hubHVtYnlAaG90bWFpbC5jb208bWFpbHRvOmpvaG5sdW1ieUBo b3RtYWlsLmNvbT4+IHdyb3RlOiAKPiDigItBcyBJIG1lbnRpb25lZCBiZWZv cmUgdGhlIGZhY3QgdGhhdCBudWxsIGlzIGEgbGl0ZXJhbC9jb25zdGFudCBp cyAgCj4gLi4uCj4g4oCLT0sgLSBwc2V1ZG8tY29uc3RhbnQgdGhlbjsgaXQg Y2FuIGJlIHVzZWQgaW4gYW55IHBsYWNlIGEgbm9ybWFsICAKPiBjb25zdGFu dCBjYW4gYmUgdXNlZCBmb3IgdGhvc2Ugc2l0dWF0aW9ucyB3aGVyZSB5b3Ug ZG9uJ3QgaGF2ZSBhICAKPiB3ZWxsLWRlZmluZWQgdmFsdWUgdG8gcHV0IHRo ZXJlLuKAiyAKPiAgCj4gVGhlIGRvY3VtZW50YXRpb24gZG9lcyBub3QgZGVz Y3JpYmUgYWxsIHBvc3NpYmxlIHZhbGlkIGNvbnN0YW50cyAtICAKPiB0aG91 Z2ggSSBhZG1pdCBnaXZlbiB0aGUgc3BlY2lhbCBuYXR1cmUgb2YgTlVMTCBp dCBwcm9iYWJseSBzaG91bGQgZG8gIAo+IHNvIGluIHRoaXMgaW5zdGFuY2Uu ICBUaGUgdHJpY2sgaXMgYXZvaWRpbmcgYWRkaW5nIGNvbW1lbnRzIHBlcnRh aW5pbmcgIAo+IHRvIE5VTEwgYWxsIG92ZXIgdGhlIGRvY3VtZW50YXRpb24g KHNlZSBiZWxvdykgYW5kIGNvbmZ1c2luZyB0aGUgIAo+IHVuZGVybHlpbmcg bm9ybWFsIG5vbi1udWxsIHVzYWdlLiAgVGh1cywgcmlnaHQgbm93LCBvbmx5 IHdoZW4gTlVMTCAgCj4gYmVoYXZpb3IgaXMgaW1wb3J0YW50IGRvZXMgaXQg Z2V0IGFkZHJlc3NlZC4gIFNFVCBjb2wgPSBOVUxMIGlzIG5vICAKPiBkaWZm ZXJlbnQgdGhlbiBTRVQgY29sICA9ICdhIHN0cmluZycgc28gd2h5IG1ha2Ug aXQgc2VlbSBsaWtlIGEgc3BlY2lhbCAgCj4gY2FzZSBieSBwb2ludGluZyBv dXQgdGhlICJvYnZpb3VzIj8gCj4gIAo+IEV2ZW4gaWYgcGVvcGxlIGFyZSBu b3QgcG9zaXRpdmUgc2ltcGx5IHRyeWluZyB3aGF0IHlvdSB3cm90ZSBpcyBl YXN5ICAKPiBhbmQgaW4gdGhlIGFic2VuY2Ugb2YgYW55IGVycm9yIGl0IHdv dWxkIGJlY29tZSBvYnZpb3VzIHRoYXQgTlVMTCBpcyAgCj4gdmFsaWQgaW4g VVBEQVRFL1NFVC4gCgpOb3QgdG8gaGFycCBvbiB0aGlzLMKgIGJ1dCBhbHRo b3VnaCAidHJ5aW5nIiBpdCBpbiB0aGUgc2Vuc2Ugb2YKwqB0eXBpbmcgaXQg aW4gYW5kIHNlZWluZyBpZiBzb21lIGVycm9yIG9jY3VycyBpcyBlYXN5LAp2 ZXJpZnlpbmcgdGhhdCBpdCBwcm9kdWNlcyB0aGUgZXhwZWN0ZWQgcmVzdWx0 IGluIHRoZSBkYXRhYmFzZQppcyBmYXIgZnJvbSBlYXN5IElGIHRoZSBwZXJz b24gZG9pbmcgaXQgY2Fubm90IGZpbmQKYW55IHNlbWFudGljIGRlZmluaXRp b24gb2YgYSBudWxsIHZhbHVlLMKgIGUuZy4gdGhlIHZhcmlvdXMKdHJpY2t5 ICJ1bmtub3duIiBydWxlcyBldGMuCgo+ICAKPiBUaGUgbGFyZ2VyIHByb2Js ZW0gaXMgcGVvcGxlIHRoaW5raW5nICJOVUxMID0gTlVMTCIgcmV0dXJucyB0 cnVlIG9yICAKPiAiTlVMTCA9ICdzb21lIG90aGVyIGxpdGVyYWwnIiByZXR1 cm5zIEZBTFNFOiBpLmUuLCB0aGF0IE5VTEwgaXMgbmV2ZXIgIAo+IHNwZWNp YWwgYnV0IGlzIGp1c3QgYW5vdGhlciBsaXRlcmFsLiAKPiAgCj4gQWN0dWFs bHkgSSBoYXZlIHNlZW4gbWFpbGluZ3Mgd2hlcmUgc29tZW9uZSBpcyBhc2tp bmcgaG93IHRvIHNldCBhICAKPiBjb2x1bW4gdmFsdWUgdG8gTlVMTCAKPiBz byBJJ2Qgc2F5IGl0IGlzIG5vdCBvYnZpb3VzLiAgICAgIEEgcmVmZXJlbmNl IG1hbnVhbCBzaG91bGQgcHJlZmVyYWJseSBhdm9pZCAKPiBhc3N1bWluZyBh bnl0aGluZyBhYm91dCB3aGF0IGl0IGlzIGRvY3VtZW50aW5nLiAKPiAgCj4g Li4uIAo+ICAKPiDigItVc2VyIGRvY3VtZW50YXRpb24gZG9lcyBub3Qgd2Fu dCB0byBjb3B5IGZyb20gc3RhbmRhcmRzLCBvciBpbiBtYW55ICAKPiBjYXNl cywgc291cmNlIGNvZGUuICBUaGUgcGVyc29uIHdyaXRpbmcgc2FpZCBkb2N1 bWVudGF0aW9uIHNob3VsZCBiZSAgCj4gaW5mb3JtZWQgYnkgdGhvc2Ugc291 cmNlcyBhbmQgdGhlbiB3cml0ZSBzb21ldGhpbmcgdGFyZ2V0ZWQgZm9yIHRo ZSAgCj4gdHlwaWNhbCB1c2VyLiAKPiAgCj4gWW91IGVudGlyZSBwYXJhZ3Jh cGggYm9pbHMgZG93biB0bzogTlVMTCBjYW4gYmUgdXNlZCBsaWtlIGEgY29u c3RhbnQgIAo+IGJ1dCB3aGVuIGNvbXBhcmVkIHdpdGggaXRzZWxmLCBvciBv dGhlciBjb25zdGFudHMsIHJlc3VsdHMgaW4gdGhlIHRoaXJkICAKPiBsb2dp Y2FsIHN0YXRlIC0gdW5rbm93bi4gCj4gIAo+IOKAi0l0IGNhbiBiZSBkZWNs YXJlZCBhcyBhIGRlZmF1bHQ6ICAgQ1JFQVRFIFRBQkxFIHRlc3QgKCBjb2wg dmFyY2hhciAgCj4gTlVMTCBERUZBVUxUIE5VTEwgKTsgCj4gIAo+IEFuZCBp dHMgdXNlIGluIGFuIGV4cHJlc3Npb24gaXMgbm90IGxpbWl0ZWQgYW55IG1v cmUgdGhhbiBhbnkgb3RoZXIgIAo+ICJ0cnVlIGNvbnN0YW50IiAKPiAgCj4g TW9yZSBvZiBhIHNlbWFudGljIGJ1dCB5b3UgY2FuIGF0dGVtcHQgdG8gaW5z ZXJ0IE5VTEwgaW50byBhIGNvbHVtbiAgCj4gaGF2aW5nIGEgTk9UIE5VTEwg Y29uc3RyYWludCAtIGl0IHdpbGwganVzdCBjYXVzZSBhbiBlcnJvci4gIE11 Y2ggbGlrZSAgCj4geW91IGNhbiBhdHRlbXB0IHRvIGluc2VydCAtMjAgaW50 byBhIGNvbHVtbiB3aXRoIGEgY29uc3RyYWludCBDSEVDSyhjb2wgIAo+ID49 IDApIAo+ICAKPiAgCj4gIAo+IE15IHJvdWdoIGlkZWEgYXQgdGhlIG1vbWVu dCBpcyB0byBpbnRyb2R1Y2UgYSBzZWN0aW9uIGluICJUdXRvcmlhbDogVGhl ICAKPiBTUUwgTGFuZ3VhZ2UiIGNoYXB0ZXIsIHN1YnNlcXVlbnQgdG8gIkpv aW5zIEJldHdlZW4gVGFibGVzIiwgYW5kICAKPiBzdW1tYXJpemUgYW5kIGNy b3NzLXJlZmVyZW5jZSB0byBvdGhlciBzZWN0aW9ucyB0aGUgY29uY2VwdCBh bmQgdXNlIG9mICAKPiBOVUxMLiAgVGhlIHRocmVlIHByaW9yIHNlY3Rpb25z IChSb3dzLCBRdWVyaWVzLCBKb2lucykgYWxsIGhhdmUgTlVMTCAgCj4gaW1w bGljYXRpb25zIHRoYXQgYXJlIG5vdCBjb3ZlcmVkIGluIHRob3NlIGNoYXB0 ZXJzIGV4cGxpY2l0bHkgYW5kICAKPiBhZGRpbmcgaXQgdG8gYWxsIHRocmVl IGRvZXNuJ3QgZmVlbCByaWdodC4gIEEgc2VwYXJhdGUgZW5jYXBzdWxhdGlu ZyAgCj4gY2hhcHRlciBzZWVtcyBiZXR0ZXIgYW5kIGxldHMgdGhlIHJlYWRl ciBmb2N1cyBvbiB0aG9zZSB0b3BpY3Mgd2l0aG91dCAgCj4gdGhlIGltbWVk aWF0ZSBkaXN0cmFjdGlvbiBvZiBOVUxMIGNvbXBsaWNhdGluZyB0aGluZ3Mu IFRoaXMgd291bGQgYmUgIAo+IHRoZSAicmVmZXJlbmNlIHNlY3Rpb24iIGZv ciB0aGUgdG9waWMuICBJZiB5b3UgdGhpbmsgb2YgdGhlIHRvcGljIGFzICAK PiBiZWluZyBhIHByZS1yZXF1aXNpdGUgdGhlbiB0aGUgdHV0b3JpYWwgZG9l cyBtYWtlIHNvbWUgc2Vuc2UgLSBhbmQgd2hlbiAgCj4gSSBkZXZpc2VkIHRo ZSBhYm92ZSBJIGRpZG4ndCByZWFsbHkgcHJvY2VzcyB0aGF0IHRoaXMgd2Fz ICJ0dXRvcmlhbCIgIAo+IG1hdGVyaWFsLi4uY29uc2lkZXJhdGlvbiBmb3Ig YW5vdGhlciB0aW1lLiAKPiAgCj4gSW4gIlNRTCBTeW50YXgiIEkgd291bGQg Y292ZXIgdGhlIHRvcGljIGFnYWluIHVuZGVyICJjb25zdGFudHMiIC0gIAo+ IHByb2JhYmx5IGNhbGxpbmcgdGhlbSBwc2V1ZG8tY29uc3RhbnQgKGluc3Bp cmVkIGZyb20gdGhlIGFib3ZlICAKPiBkaXNjdXNzaW9uKS4gCj4gIAo+IEkn bSB1bmNlcnRhaW4gb24gd2hldGhlciBvciBob3cgdG8gY292ZXIgdGhlbSB3 aXRoaW4gdGhlICJEYXRhIFR5cGVzIiAgCj4gY2hhcHRlciBidXQgZmVlbCBs aWtlIGl0IHNob3VsZCBiZSBtZW50aW9uZWQgdGhlcmUgYXMgd2VsbC4gCj4g IAo+IERhdmlkIEouIAo+ICAKClllcyzCoMKgIEkgYWdyZWUsIMKgIHRoYXQg YWxsIHNvdW5kcyBnb29kLArCoCDCoMKgIGFuZCBhbHNvIHRoYW5rcyBmb3Ig Y29ycmVjdGluZyBmYWN0dWFsIGVycm9ycyBpbiBteSB2ZXJzaW9uLgoKSSBo YXZlIHR3byBjb21tZW50cyzCoCBvbmUgb2Ygd2hpY2ggSSB0aGluayB5b3Ug bWF5IGhhdmUgYWxyZWFkeSBhZGRyZXNzZWQ6CgoxIC7CoMKgIHdvdWxkIGJl IGdvb2QgaWYgdGhlIGRvY3VtZW50YXRpb24gZGlzdGluZ3Vpc2hlcwrCoCDC oCBiZXR3ZWVuIHR3byBzbGlnaHRseSBkaWZmZXJlbnQgcG9pbnRzOgrCoMKg wqDCoCAuwqDCoMKgIHRoZSBzZW1hbnRpYyBtZWFuaW5nIG9mIGEgbnVsbCB2 YWx1ZQrCoMKgwqDCoCAuwqDCoCB2YWxpZCBzeW50YWN0aWMgdXNlcyBvZiB0 aGUgdG9rZW4gTlVMTAoKMi7CoMKgwqAgSSBzdWdnZXN0IGluY2x1ZGluZyBz b21ld2hlcmUgZXhwbGljaXQgZXhhbXBsZXMgb2YKwqAgwqAgwqDCoCBzZXR0 aW5nIGEgY29sdW1uIHZhbHVlIHRvIE5VTEwKwqDCoMKgwqDCoCBhKcKgIGlu IGEgVkFMVUVTIGNsYXVzZSBvZiBJTlNFUlQKwqDCoMKgwqDCoCBiKcKgIGlu IGEgU0VUIGNsYXVzZSBvZiBVUERBVEUKIAkJIAkgICAJCSAgCi0tIApTZW50 IHZpYSBwZ3NxbC1kb2NzIG1haWxpbmcgbGlzdCAocGdzcWwtZG9jc0Bwb3N0 Z3Jlc3FsLm9yZykKVG8gbWFrZSBjaGFuZ2VzIHRvIHlvdXIgc3Vic2NyaXB0 aW9uOgpodHRwOi8vd3d3LnBvc3RncmVzcWwub3JnL21haWxwcmVmL3Bnc3Fs LWRvY3MK