Why can't a primary key be duplicated?
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From: torijoshmom on 25 Mar 2010 23:05 Why can't a primary key be duplicated in Access?
From: Ken Snell on 25 Mar 2010 23:16 Because a primary key, by definition, identifies a unique record within a table. If it can be duplicated, then you don't have uniquely identifiable records in your table. -- Ken Snell http://www.accessmvp.com/KDSnell/ "torijoshmom" <torijoshmom(a)discussions.microsoft.com> wrote in message news:ECB13770-C283-48A0-BC94-8374572F4E4E(a)microsoft.com... > Why can't a primary key be duplicated in Access?
From: Tony Toews [MVP] on 25 Mar 2010 23:18 torijoshmom <torijoshmom(a)discussions.microsoft.com> wrote: >Why can't a primary key be duplicated in Access? For the same reason you can't have the same address referring to two different buildings. Tony -- Tony Toews, Microsoft Access MVP Tony's Main MS Access pages - http://www.granite.ab.ca/accsmstr.htm Tony's Microsoft Access Blog - http://msmvps.com/blogs/access/ For a convenient utility to keep your users FEs and other files updated see http://www.autofeupdater.com/ Granite Fleet Manager http://www.granitefleet.com/
From: Jerry Whittle on 26 Mar 2010 10:55 It's not just Access. No relational database will allow duplicate data in the primary key field of a table. -- Jerry Whittle, Microsoft Access MVP Light. Strong. Cheap. Pick two. Keith Bontrager - Bicycle Builder. "torijoshmom" wrote: > Why can't a primary key be duplicated in Access?
From: Paul Shapiro on 26 Mar 2010 12:41
Maybe if you describe the table, its definition, and the columns in the table someone might be able to suggest a better data structure and/or a better primary key. As others said, a unique primary key is a requirement in a properly designed data structure. "Jerry Whittle" <JerryWhittle(a)discussions.microsoft.com> wrote in message news:26E1C8FD-1A28-44D7-8C3D-1EE8711BE72F(a)microsoft.com... > It's not just Access. No relational database will allow duplicate data in > the > primary key field of a table. > -- > Jerry Whittle, Microsoft Access MVP > Light. Strong. Cheap. Pick two. Keith Bontrager - Bicycle Builder. > > > "torijoshmom" wrote: > >> Why can't a primary key be duplicated in Access? |