12.9
Using a Relational Database and the Extensible Markup Language to Store and Distribute Climate Metadata
Roland H. Schweitzer, NOAA/CDC and CIRES/Univ. of Colorado, Boulder, CO
In this paper, we describe our experiences using a relational database, the Extensible Markup Language (XML) and style sheets to store and distribute climate metadata. We report on the advantages and disadvantages of this technique. We also discuss how we think this emerging technology will evolve in the near future.
As climate data providers we are often asked to create metadata descriptions of our data. People that make the requests need the metadata in different formats. We also use metadata in different formats. For example, our Web site has a Hypertext Markup Language (HTML) page that uses metadata to describe each climate data set we redistribute to the public. We also have metadata stored in the Federal Geographic Data Committee (FGDC) format, which is used by NOAAServer (a geographically distributed data access and retrieval system on the World Wide Web).
We also store metadata in a small public-domain relational database, so users can search the it through a Web interface,. We want to use the database to help create metadata files we need in different formats. One approach would be to write programs to create metadata reports in various formats directly from the database. However, we hope to create a more flexible solution by using XML as an intermediate data format.
XML is a data format for structured document interchange on the Web. In XML we can define our own tags. These tags are used to delimit sections of information based on content, rather than indicating how to display it. We can also create a style sheet that is used on the Web together with the XML file. The style sheet tells the Web browser what information it should extract from the XML and how to display it. This solution is more flexible, because a person viewing the metadata on the Web can switch easily between formats without making a request of the Web server. Using this approach, a new style sheet is all we need to create metadata in a new format.
Session 12, Applications of decision support tools in the use and leverage of the Internet (Parallel with Sessions 11 and 13)
Thursday, 13 January 2000, 8:30 AM-12:15 PM
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