Revision 1309666

HIVE-2822 [jira] Add JSON output to the hive ddl commands
(Chris Dean via Ashutosh Chauhan)

Summary:
JSON output for DDL commands

By setting the variable hive.format=json then ddl commands will
produce json output suitable for client side parsing.  For example, to
list all the databases one might get:

    {
      "databases": [
        "default"
      ]
    }

The goal is to have an option to produce JSON output of the DDL commands that is
easily machine parseable.

For example, "desc my_table" currently gives

    id    bigint
    user  string

and we want to allow a json output:

    {
      "columns": [
        {"name": "id", "type": "bigint"},
        {"name": "user", "type": "string"}
      ]
    }

Test Plan: Run the provided unit tests

Reviewers: JIRA, ashutoshc

Reviewed By: ashutoshc

Differential Revision: https://reviews.facebook.net/D2475