[support] Auto increment CCK vid and/or nid?

I've been getting a bunch of duplicate entry errors on a site, something like this:

user warning: Duplicate entry '81-0' for key 1 query: INSERT INTO content_field_testimonial (vid, nid, delta, field_testimonial_value, field_testimonial_format) VALUES (81, 81, 0, '<p><em> ...trimmed... /sites/all/modules/cck/content.modulehttp://judylarkins.com/html/sites/all/modules/cck/content.moduleon line 1213.

Some searching suggests auto-incrememnt is not set, and in fact none of the fields in the content_field_testimonial are auto-incrementing. However, before I arbitrarily assign auto-increment to any of the fields, I thought I'd ask which if any should be auto-incrementing: vid, nid, delta, field_ccktype_value, field_ccktype_format.

Thanks, Brian