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diff --git a/development/pim/dbpaper/intro.tex b/development/pim/dbpaper/intro.tex index c456333..fd790d7 100644 --- a/development/pim/dbpaper/intro.tex +++ b/development/pim/dbpaper/intro.tex @@ -3,35 +3,35 @@ \subsection{This document} Note: This paper is just a request for comment! Don't expect to find anything in the real implementation ! \\ This draft paper describes the database layout of the Opie PIM applications. Design goal is a fast and extendable layout on a sql database to support cross referencing. \subsection{Copyright} Copyright notice -\copyright 2002, Maximilian Rei{\ss} \& Stefan Eilers \& Holger Freyther +\copyright 2002-2004, Maximilian Rei{\ss} \& Stefan Eilers \& Holger Freyther \pagebreak \section{Relations} \subsection{About Cross Referencing and Horizontal Data Storage} Before you read on, it may be helpful to get some information about the solution of ``horizontal'' data storage into the tables and cross referencing. Some of the tables are just using 5 attributes: \begin{enumerate} \item UID: This countains an unique ID for the complete entry. An entry may consist of multiple rows, seperated by ID. -\item ID: This defines a number to seperate the rows of an entry. UID + ID must be unique for every entry. +\item ID: This defines a number to seperate the rows of an entry. UID + ID must be unique for every entry (primary key). \item Type: Describes the type of this entry. \item Priority: For instance: Your default email-address will get the priority 1 and the other 2.. . 0 means ``not defined''. \item Value: The data which was described by ``Type'' is stored here. \end{enumerate} These kinds of tables are very flexible in what they may contain, due to the fact that the ``Type'' may be without any constraint. Therefore it is perfectly for storing personal information, which may change in the future, or should be increased. \\ Let's see how such an entry may look like for the table ``ADDRESSBOOK'': \begin{tabular}[ht]{|l|l|l|l|} \hline \underline{UID} & \underline{ID} & Type & Value\\ |