Leap2A mapping

Belongs to the 2009-03/Leap2A specification, written March 2010

Guide to explaining and documenting mappings to Leap2A
The objectives of a mapping are twofold: The second may well be more challenging. You will need to make explicit things which may not be obvious to others.
 * 1) to note for yourself how you have decided to map things, to guide those who implement Leap2A for your system
 * 2) to explain to others how you have decided to map things.

Diagrammatic guides can be very helpful and illustrative, but principally, for ease of reference, as well as construction, a tabular format is suggested. However, the mapping is often not one-to-one between system elements and Leap2A elements. So be prepared to use more than one line for a mapping, either several of your elements mapping onto one Leap2A element, or, more likely, one of your elements mapping onto several Leap2A elements.

On your side, you may want to document any or all of (perhaps in columns) If you have good reasons not to make your database structure public, the essential details (which cannot be kept secret in any case) are
 * name of field
 * data type
 * database table
 * field name in database table
 * web page(s) appearing in demo system on which information appears
 * example content, or (if long) typical length of content
 * web page(s) appearing in demo system on which information appears, allowing people to refer to the interface
 * any heading appearing on the page, indicating the nature of the content
 * example content, or (if long) typical length of content

On the Leap2A side, to be as clear as possible, any of these following may need to be detailed. Remember that there may be more than one Leap2A entity involved in representing something you think of as one entity. If you are mapping to a whole Leap2A item, you need to know: If you are mapping to a part of an item, you need to know the Leap2A "path", along with any significant types, etc. along the way.
 * rdf:type of Leap2A item used to represent this information
 * title of that item (what do you use for the title?)
 * what is in the content of that item
 * any required categories of that item
 * what links are needed from that item
 * the relationship
 * the object of the relationship

Exactly how you display and document these is a matter of personal choice and style. However, you will only have completed the mapping task when all of this information is decided -- and checked with me and others -- so it really needs to be able to be understood by us.

The mapping task is to some extent iterative. You cannot expect to get it "right" at the first attempt, or to make it communicate perfectly. Therefore, the sooner you start to share and check your mappings, the sooner you will approach something that will actually work for export and import.

Ideally, you would also then document the Leap2A XML to be (or actually) generated for this information. (If you have your own proprietary XML format, this should be shown alongside.)

One further consideration. When you import Leap2A, you will be looking out for patterns matching the patterns you have generated on export. Therefore, make sure that the mapped patterns of each of your different elements are distinguishable. Even just one different category may be sufficient to distinguish two different patterns; or the presence of a particular kind of link to a particular other kind of item. Try to find other systems that have similar information, and be sure to use the same ways of doing the same things as other people have used.

You are welcome to discuss your mappings with me at any convenient time. Then you should also check with other PIOP partner projects. Then implement your export, and give examples of the resulting Leap2A XML (or zip files) to established partners to see what they make of it on import.

Please keep the latest version of your mappings available on your PIOP 3 web page. Remember that this is publicly available, so please don't put confidential information anywhere on your PIOP 3 page. Look at other people's mappings, and look at your own from other people's point of view. Feel free to ask questions about other projects' mappings.