On Wed, 18 Jul 2001 11:03:11 -0700, Dan Goldberg wrote: >I can not edit data in a view in the windows version of R:base but I could in the DOS version. I pressed [F4] and I am in data editor but I still can not edit anything. Dan, I just did a test, and was able to edit and update a table through a simple view of that table from the RBWin browser/editor. In either the DOS or Windows version, it is very easy to make a view "non-updatable." For example, if you "sort" a view, either by putting an ORDER BY clause in the definition, or by sorting the browser window, it is no longer updatable. This is part of the SQL definition of a view. Here are the SQL rules for a view being updatable, from "SQL Instant Reference" by Martin Gruber, Sybex, ISBN 0-7821-4413-3: "* It must be drawn on one and only one simply underlying table. In other words, no joins. *It must contain one and only one query, in other words, no usage of UNION, EXCEPT, or INTERSECT *If the simply underlying table is itself a view, that view also must be updatable *The SELECT clause of the contained query may only specify column references, not value expressions or aggregate functions, and no column may be referenced more than once *The contained query may not specify GROUP BY or HAVING *The contained query may not specify DISTINCT." The books continues with this: "These are fairly stringent restrictions, and some products may relax them." And from the same book: "As with a base table, the rows of a view are by definition unordered. Therefore, ORDER BY may not be specified." Bill
