Hopefully during our research we will run into fellow researchers who would like to exchange our data. But very often they will use one of the many other genealogical programs.
Besides, Genj is a great application, but …
- There is no application that fits for all my needs. There are always specialists for special needs.
- There will be a successor for GEDCOM, where we (or our successor) would like to migrate to.
- Maybe, my ambition as a researcher will grow and I need much more support in the research process.
- Every application will eventually become obsolete. With new technologies new applications will emerge.
Inspite GEDCOM was developed to foster the data exchange between genealogical programs there are often problems with exchanging data between applications. yet
The most insidious problem is:
The exporting researcher doesn't know that his data has been mangled and the importing researcher doesn't either!
This is a problem for applications that have an own database to store the information and to extract it into GEDCOM format. In contrast is GenJ storing all its information into GEDCOM immediately and thus avoids garbling information on reading and saving.
The main reasons are (roughly in that sequence):
- Users misuse tags.
- Applications are not updated to the current version of the standard.
- The standard was misunderstood by the application developers.
- The standard is incomplete or not up-to-date to actual needs.
- The standard is ambiguous.
The standard allows user defined tags (_<ABCDE>). These are per definition unknown for receiving applications.
The following lists some further problem areas for data exchange.
Applications are not completely conform to the standard and often mangle:
- the precedence of a person's multiple names
- the relative birth order among his siblings (especially when some birth dates are unknown)
- in general the precedence of multiple same tags in a »context«1)
- incomplete/ambiguous dates
- dis-aggregate sources (is this »Johnson Family Bible« the same as that »Johnson Family Bible«?)
- the format of notes (e.g. extraneous carriage returns)
- the researcher's knowledge about a place (is »Washington« a city or state?)
- standard tags they don't know
The standard is incomplete or not up-to-date to actual needs:
- witnesses of marriage
- research tasks planning (_TODO)
- naming conventions of persons in different cultures
- German: Rufname (engl. 'known by')
- BAPM and CHR
- direction of association (ASSO)
The following hints may reduce the data exchange problems:
- Don't use User-defined (nor vendor-specific!) tags, see GEDCOM Usage Recommendations
- Save those information in notes that are not likely to be interpreted automatically by a program, e.g. for statistics or sorting.
- Avoid to use eccentric (seldom used) tags; in doubt use notes
- Record complete jurisdiction or coordinates, see Place specifications
- Perform plausibility check before exchanging data, see GenJ Usage Recommendations
- in general: follow GEDCOM Usage Recommendations
Further keywords: data migration, portability