All five RDBMSs offer at least some support for XML data types and related operations. The enterprise class RDBMS such as IBM DB2, Oracle and Microsoft SQL Server have implemented most of the features defined in SQL:2006 standard. The desktop databases such as Microsoft Access and OpenOffice.org BASE do not support XML as part of their SQL implementation, but enable manipulating the XML documents using built-in languages: VBA and Basic, respectively.
Details of implementation differ between various RDBMSs.
XML documents inside RDBMSs can be stored in various formats, including an unstructured character string, shredding into a set of relational tables, and a native XML data type.
Storing, retrieving, and manipulating XML information involves understanding XQuery, XPath, and SQL/XML concepts because manipulation can be performed on very fine-grained levels — those of XML elements and attributes.
Columns of the XML data type can be indexed in a similar fashion as other built-in data type columns.
Even by itself, XML is a vast topic, and there are many sources of information about it, including the aforementioned www.w3.org, which is the “horse's mouth” because it is the source of the original specification (it is not always easily intelligible, however). Other sources include vendor documentation, various blogs and pages, and, of course, books.
The full-text search in the text fields is made possible with creating special indices and utilizing SQL functions implemented by ...