I like to make org-mode tables in arbitrary buffers, then save them as CVS files. The export fails when done from a buffer with no associated file.
Here's a little patch that allows exporting a table from any buffer (org-mode version 6.28trans):
diff --git a/lisp/org-table.el b/lisp/org-table.el
index 410f721..4b85f97 100644
--- a/lisp/org-table.el
+++ b/lisp/org-table.el
@@ -471,8 +471,9 @@ property, locally or anywhere up in the hierarchy."
(error "Abort")))
(if (file-directory-p file)
(error "This is a directory path, not a file"))
- (if (equal (file-truename file)
- (file-truename (buffer-file-name)))
+ (if (and (buffer-file-name)
+ (equal (file-truename file)
+ (file-truename (buffer-file-name))))
(error "Please specify a file name that is different from current"))
(unless format
(setq deffmt-readable org-table-export-default-format)