List: | General Discussion | « Previous MessageNext Message » | |
From: | Brent Baisley | Date: | September 15 2003 3:47pm |
Subject: | Re: Does NULL == ""? | ||
View as plain text |
This is sometime a tough concept to get through. For example, there is more than two answers to a yes and no question. There is yes, no, "I don't know" (the empty set) and the "No answer at all" (null). It's almost useless to specify a property as NOT NULL and also set a default value. The only way it would ever be NULL is if you specifically set it to NULL. If you see an empty field in a database, you have to wonder if someone forgot to enter a value or if there was no value to enter. The difference between NULL (no value entered) and "" (no value to enter). On Monday, September 15, 2003, at 11:00 AM, Randy Chrismon wrote: > The MySQL documentation confuses me a bit. If I create a table with > property NOT NULL and default "", does that mean that a record with a > column so defined will have a zero-length string in that column if I > don't provide a value? I guess what I'm asking is whether there's a > difference between a field with NULL in it and a field with a > zero-length ("") string in it. > -- Brent Baisley Systems Architect Landover Associates, Inc. Search & Advisory Services for Advanced Technology Environments p: 212.759.6400/800.759.0577
Thread | ||
---|---|---|
• Does NULL == ""? | Randy Chrismon | 15 Sep |
• Re: Does NULL == ""? | Bruce Feist | 15 Sep |
• RE: Does NULL == ""? | Mark Richards | 15 Sep |
• Re: Does NULL == ""? | Brent Baisley | 15 Sep |
• Re: Does NULL == ""? | Keith C. Ivey | 15 Sep |
• Re: Does NULL == ""? | Paul DuBois | 15 Sep |
• Re: Does NULL == ""? | Alec.Cawley | 15 Sep |
• RE: Does NULL == ""? | Mark Richards | 15 Sep |
• Re: Does Null == ""? | Randy Chrismon | 15 Sep |
• RE: Does Null == ""? | Mark Richards | 15 Sep |
• Re: Does Null == ""? | Bob Hall | 16 Sep |
• Re: Does Null == ""? | Bruce Feist | 16 Sep |
• Re: Does Null == ""? | Dan Nelson | 16 Sep |
• Re: Does Null == ""? | Bruce Feist | 16 Sep |
• Re: Does Null == ""? | Bob Hall | 16 Sep |
• Re: Does Null == ""? | Bob Hall | 16 Sep |
• RE: Does Null == ""? | Jon Frisby | 16 Sep |
• Re: Does Null == ""? | Bruce Feist | 16 Sep |
• RE: Does Null == ""? | Jon Frisby | 16 Sep |
• Re: Does Null == ""? | Bruce Feist | 16 Sep |
• RE: Does Null == ""? | Jon Frisby | 16 Sep |
• Re: Does Null == ""? | Bob Hall | 17 Sep |
• Re: Does Null == ""? | Bob Hall | 16 Sep |
• Re: Does Null == ""? | Bob Hall | 16 Sep |
• Re: Does Null == ""? | Bob Hall | 17 Sep |
• Re: Does Null == ""? | Bruce Feist | 18 Sep |
• Re: Does Null == ""? | Bob Hall | 18 Sep |
• Re: Does Null == ""? | Haydies | 18 Sep |
• Re: Does Null == ""? | Bob Hall | 18 Sep |