Native XML database and DBMS

XML is a popular data format which can be stored, processed and analyzed in traditional relational DBMS as well as new breed of database called native XML DB (NXD).

Traditional relational database can store the XML as (Connolly & Begg, 2014):

1. Value of some attribute within a tuple using data type of character large object (CLOB)

2. Shredded form in several attributes and relations by decomposing into constituent elements

3. transforming XML schema into relational mapping or object-relational mapping

4. Schema independent form

5. Parsed form (converting XML to internal format etc.)

Native XML database (NXD) is a new emerging type of database that supports the retrieval and storage of XML in its native format (Connolly & Begg, 2014). NXD should be supporting all the necessary attributes of typical database like security, recovery, concurrency, and transactions. Usual database operations like insert, delete, modify etc. are supported in NXD. XML DBMS can be broken into text-based and model based types. Text-based stores in the form of text while model-based stores in the form of XML tree schema. XPath is currently used as the NXD query language (Staken, 2001). Since XPath was not designed as a database query language which is why there are some limitations like lack of grouping, sorting, data type etc. support. NXD supports the creation of indices which further improves the performance. Some popular NXDs are MarkLogic server, Ipedo XMLDB, Tamino, open-source BaseX, open-source Xindice etc.

Pros and Cons of NXD

NXD can work only on XML not the other way round which is why it is a preferable solution for document-oriented data with complex structure usually found in corporate information portal, catalog data, manufacturing parts database, medical information storage, document management systems, etc. (Staken, 2001). However NXD is not a preferred solution for traditional well-defined data sets like finance, accounts etc.

Pros and Cons of Relational DBMS

Relational DBMS has evolved over several decades and provide efficient and robust solution for traditional data in rows and columns formats. Owing to significant adaptation of XML across industries, relational databases has added support of XML over the period of time, like Oracle XML development kit and Oracle XML DB (Connolly & Begg, 2014).

Reference

Connolly, T. M., & Begg, C. E. (2014). Database systems: a practical approach to design, implementation, and management. New Jersey, NJ: Pearson.

Staken, K. (2001). Introduction to native XML databases. Retrieved from http://www.xml.com/pub/a/2001/10/31/nativexmldb.html