Re:Yes, there is: Koha. (Score 2)

MARC is an extremely flexible data structure. Relational databases tend to view the world as a set of linked tables with data elements. Of course as anyone who has ever survived a CS data structures course can tell you, you can use almost any data structure to store any other data structure. Its mostly a matter of efficiency. Yes, people have stored MARC data in a relational database. It worked, sorta of. Think of a table where any column could be repeated any number of times, or omitted, or be of any length, or .... A book can have no authors, or 1 author or lots of authors, or some authors are really corporations, and other authors are really pseudonyms, and some authors have different names in different languages. Not an insurmountable problem if all you have is a relational database. The usual method is breaking the MARC record up into lots of itty-bitty pieces. You have the author table, the title table, the uniform title table, the serial title table, etc. The problem with breaking it up is you have to put it all back together again. Think about doing a join across 900 different tables. At this point CJ Date starts in with denormalizing your data.... Its a case of when you have a hammer everything looks like a nail. Relational databases have their place, but they aren't always the best way to store and retrieve all types of data. There are databases which aren't relational, and sometimes they outperform a relational database on specific types of data.