Paul Clapham wrote:If you are writing a serious application you should store the data in GEDCOM format. This seems to be the lingua franca of the genealogy world.
NO, no, no, a thousand times no. GEDCOM is the external transfer language, the least common subset of requirements. Yes, you must be able to import and export from and to GEDCOM, but you do not want to use that internally. GEDCOM was invented by the Mormons (Church of Latter Day Saints) for their own theological needs. It meets them, but it does not meet the needs of general genealogy research. The LDS have stated that they do not intend to revise the standard, it suits their needs well.
Any relational DBMS will work fine. You do have to make is support how complicated real world families are. My grandfather had three wives, so you had better not just have a structure to support one. A multi-linked tree is probably the right in-memory datastore, as genealogy is usually a directed graph.
There is an old bluegrass standard song about this: "I am my own grandpa"