Thread: Null and Not Null
** Reply Requested When Convenient ** Can some one please help me understand Null and Not Null Thanks Mike Hammonds, CNE5, MCP-NT Fellon-McCord & Associates, Inc. Office: 502.214-6324 Fax: 502.426.8800 mhammonds@knowledgeinenergy.com Show Me the Code!!
Attachment
Hi Mike, Your question is sort of broad. Could you be more specific? However, a general reply to your broad question (and a source of confusion for many people) is that Null does not mean "empty", rather it means "undefined" (as in "the answer to a poorly formed question") -- which is why Null = Null is false. Thanks, David Boerwinkle ----- Original Message ----- From: Mike Hammonds <mhammonds@knowledgeinenergy.com> To: <pgsql-novice@postgresql.org> Sent: Tuesday, December 26, 2000 9:43 AM Subject: [NOVICE] Null and Not Null ** Reply Requested When Convenient ** Can some one please help me understand Null and Not Null Thanks Mike Hammonds, CNE5, MCP-NT Fellon-McCord & Associates, Inc. Office: 502.214-6324 Fax: 502.426.8800 mhammonds@knowledgeinenergy.com Show Me the Code!!
Look at http://www.comptechnews.com/~reaster/dbdesign.html#three-valued-logic Might be helpful. On Tuesday 26 December 2000 10:43, Mike Hammonds wrote: > > ** Reply Requested When Convenient ** > > Can some one please help me understand Null and Not Null > > Thanks > > Mike Hammonds, CNE5, MCP-NT > Fellon-McCord & Associates, Inc. > Office: 502.214-6324 > Fax: 502.426.8800 > mhammonds@knowledgeinenergy.com > Show Me the Code!! ---------------------------------------- Content-Type: text/plain; charset="US-ASCII"; name="Attachment: 1" Content-Transfer-Encoding: 7bit Content-Description: ---------------------------------------- -- -------- Robert B. Easter reaster@comptechnews.com --------- - CompTechNews Message Board http://www.comptechnews.com/ - - CompTechServ Tech Services http://www.comptechserv.com/ - ---------- http://www.comptechnews.com/~reaster/ ------------