Sedna is an open-source database management system that provides native storage for XML data.
The distinctive design decisions employed in Sedna are (i) schema-based clustering storage strategy for XML data and (ii) memory management based on layered address space.
[1] Data organization in Sedna is designed with the goal of providing a balance in performance between XML queries and updates execution.
[1] The two primary design decisions in data organization in Sedna are: The following figure illustrates the overall principles of data organization in Sedna.
Data blocks related to a common schema node are linked via pointers into a bidirectional list.
<library>
<book>
<title>Foundations of Databases</title>
<author>Abiteboul</author>
<author>Hull</author>
<author>Vianu</author>
</book>
<book>
<title>An Introduction to Database Systems</title>
<author>Date</author>
<issue>
<publisher>Addison-Wesley</publisher>
<year>2004</year>
</issue>
</book>
...
<paper>
<title>A Relational Model for Large Shared Data Banks</title>
<author>Codd</author>
</paper>
</library>