Help for OAI:

What is OAI-PMH?

  The Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH) is a format for exchanging metadata records in a standardized and machine-parseable way. If you choose to enable the OAI server plugin, then your CWIS site will also be an OAI Repository from which others can pull records.

  Wikipedia's Open Archives Initiative page gives a more detailed summary of the OAI project, and more technical data on OAI-PMH can be obtained from the OAI-PMH protocol definition

What is XSD?

  OAI-PMH provides data in an XML dialect. While this can be helpful in that there are numerous tools to work with XML data, it can also be problematic in that XML is so extensible that it can be difficult to interpret. XSD a schema description language which can be used to define the structure of an XML document (see Wikipedia: XSD for mor detail).

  CWIS can serve OAI data in a number of standard formats, and has an XSD avaialble for each of those formats.

  If you choose to define a custom data format, then CWIS can generate an XSD for you to use. To use this facility, specify {CWIS_ROOT}/index.php?P=P_OAIPMHServer_XSD&FN={FORMAT_NAME} as the Schema Defintion URL when you define or edit your custom format. {CWIS_ROOT} should be replaced by the base URL of your site, and {FORMAT_NAME} should be replaced by the name of your custom format.

  The generated XSD will use <xs:include> elements to incorporate namespaces defined by your schema. When you have a field which supports multiple qualifiers, CWIS will attempt to compose them with an <xs:union>. Depending on which qualifiers must be composed in this way, and which validation tools are employed, this may result in an XSD which fails to validate.

  Note that differing XSD validation suites will often give different calidation results and that some of the more popular XML software, most notably libxml2, contains incomplete or non-compliant XSD validation functionality. Therefore, if your schema includes fields which compose multiple namespaces, then getting your XSD to validate in a cross-parser way may be difficult. In this case, your best option may be to use the CWIS-generated XSD as a starting point which can be refined.