I wonder if ZODB is suitable for the following problem, which I'll describe in relational terms: There are articles and writers (authors). Each article has at least one writer, but it can have more than one writer. I need to list all articles of a given writer, and all writers of a given article. A pure relation database solution would be as follows: To escape putting list of writers in 'articles' table, there is an 'article-writer' table, called 'aw'. It contains valid combination of writers & articles. aw table has these columns: a, w. articles table has these columns: a,other-data writers table has these columns: w,other-data To list all articles of a writer No.1 : SELECT aw.a, articles.other-data FROM aw, articles, writers WHERE aw.w=1 AND writers.w=1 AND articles.a=aw.a To list all writers of article No.2: SELECT FROM aw,articles,writers WHERE aw.a=2 AND article.a=2 AND writers.w=aw.w Is there an OO solution to this situation? -- Milos Prudek, confused ZODB newbie