On 12 September 2016 at 12:28, Craig Ringer <craig@2ndquadrant.com> wrote: >> I'll take a closer read-through shortly.
>DEFAULT > isn't a normal literal, it's an xpath expression evaluated at the same > time as the rowexpression.
Sorry for the spam, but turns out that's not the case as implemented here. The docs you referenced say it should be an xpath expression, but the implementation here is of a literal value, and examples elsewhere on the Internet show a literal value. Unclear if the referenced docs are wrong or what and I don't have anything to test with.
Feel free to fix/trim the DEFAULT related changes in above docs patch as needed.
Also, tests/docs should probably cover what happens when PATH matches more than one element, i.e. produces a list of more than one match.
It is there for case, when this is allowed. When you change the target type to any non XML type, then a error is raised.
I didn't write a negative test cases until the text of messages will be final (or checked by native speaker).