Implementation of the DDI at the Roper Center A Pilot Project on Resource Integration Marc Maynard and Hui Wang The Roper Center for Public Opinion Research University of Connecticut IASSIST Conference 2003, Ottawa, Canada

Introduction First systematic attempt to integrate DDI with existing metadata resources Project plan includes –review of metadata resources and relationships –evaluation and selection of appropriate DDI elements, –mapping of existing fields to DDI elements –development of software to extract metadata and generate XML documents Develop base of experience to evaluate further integration

Description of Metadata Resources Catalog of Holdings –study level –15,000 records –only studies for which raw data is housed at the Center –MS-Access database iPOLL –variable level –400,000 records –includes studies for which data is not housed at the Center –Oracle 8i database Pre-2003 these systems were independent of each other

DDI Elements Review of 30± recommended elements Focus 1. Document description 2. Study description 3. Data file description Consider –User requirements –Nature of collections

DDI-Database Mapping DDI Codebook DTD (40 selected elements) Roper Center Databases Roper Center Database Mapping to the DDI DTD

Mapping Issues Semantic differences Existing metadata deficiencies –current database table structure –inconsistent entries –incomplete entries Prompts further general evaluation of metadata –Avoid “work with what you’ve got”

Mapping Scheme Developed a preliminary scheme 1. Document description (4 of 10 elements) 2. Study description (11 of 17 elements) 3. Data file description (8 of 13 elements) Most critical elements mapped successfully

Mapping Scheme - Sec. 2

Application Development Java (JDBC) App Oracle Database XML document To simplify and stabilize application development the catalog was ported to Oracle

Application Development Prototype application –Java (JDBC) –Two versions Java application –allow staff to generate static xml documents for placement on the web Browser interface (JSP) –allow outside users to dynamically generate xml documents when requested

Application Development Oracle Database 1. User provide s study number 2. Search the database for metadata 3. metadata is retreived 4. Generate an XML document 5. XML document is made available to user Tomcat 4.1 Server

Future Actions Resolve mapping issues Address metadata deficiencies –Modify catalog database structure to accommodate DDI elements not successfully mapped –Complete catalog records Map iPOLL database to DDI section 4 (variable-level) Determine best way to manage and make available metadata to user groups Employ DDI XML to provide better finding aids and more integrated data access