Re: extend JSON_TABLE top level path expression

hi.

https://www.postgresql.org/docs/current/functions-json.html#FUNCTIONS-SQLJSON-TABLE
JSON_TABLE (
    context_item, path_expression [ AS json_path_name ] [ PASSING {
value AS varname } [, ...] ]

I quickly realized I didn't have tests that path_expression is not String
A_Const and PASSING clause is not NULL.  so I changed existing tests
to cover this
scenario.

The rest of the patch remains the same as v1.


--
jian
https://www.enterprisedb.com/