TAJO-1627 Rest API should support this type of query "select 1"

[charsyam]

Currently, Tajo Rest API supports well "select * from table" or "select count from table" <-- normal type
but, Tajo Rest API couldn't support this type of query like "select 1" <-- direct return type
to solve this, queries api should support resultset also.
so I suggest this.
queries return 201 Created when it is normal type of query
and query is direct query type and return 200 with result
like this (direct return type)
{"resultCode":"OK","schema":{"fields":[{"name":"?number","typeDesc":{"dataType":
{"type":"INT4"}
}}],"fieldsByQualifiedName":
{"?number":0}
,"fieldsByName":{"?number":[0]}},"serializedTupes":["AAAAAAE\u003d"]}

[hyunsik]

Hi @charsyam,

The proposal looks good to me. I have one suggestion. The JSON schema for Tajo schema looks different from those of other APIs. It would be great if they are consistent.