query "SELECT * FROM (SELECT 1, 2, 3) AS t1;" got error:No dataNode found

[irene-coming]

• dble version：
  5.6.29-dble-9.9.9.9-287a2f4-20180921052651
• preconditions ：
  reference: https://dev.mysql.com/doc/refman/8.0/en/join.html

A table_subquery is also known as a derived table or subquery in the FROM clause. See Section 13.2.11.8, “Derived Tables”. Such subqueries must include an alias to give the subquery result a table name, and may optionally include a list of table column names in parentheses. A trivial example follows:
SELECT * FROM (SELECT 1, 2, 3) AS t1;

• steps：
  step1. execute query with dble business port

mysql> SELECT * FROM (SELECT 1, 2, 3) AS t1;
ERROR 1046 (HY000): No dataNode found ,please check tables defined in schema:mytest
mysql> explain SELECT * FROM (SELECT 1, 2, 3) AS t1;
ERROR 1105 (HY000): java.lang.NullPointerException

• expect result：
  1. step1 query success
• real result：
  1. step1 query fail
• supplements：
  1.

/label ~BUG

[yexiaoli88]

verified on version: 5.6.29-dble-9.9.9.9-21b7b82-20180925034029