Error when using(subquery column)

[FlyingMao]

steps:

mysql> CREATE TABLE a_test(`id` int(10) unsigned NOT NULL,`t_id` int(10) unsigned NOT NULL DEFAULT '0',`name` char(120) NOT NULL DEFAULT '',`pad` int(11) NOT NULL,PRIMARY KEY (`id`),KEY `k_1` (`t_id`));
Query OK, 0 rows affected (0.03 sec)

mysql> CREATE TABLE a_order(`id` int(10) unsigned NOT NULL,`o_id` int(10) unsigned NOT NULL DEFAULT '0',`name` char(120) NOT NULL DEFAULT '',`pad` int(11) NOT NULL,PRIMARY KEY (`id`),KEY `k_1` (`o_id`));
Query OK, 0 rows affected (0.03 sec)

mysql> insert into a_test values(1,1,'test中id为1',1),(2,2,'test_2',2),(3,3,'test中id为3',4),(4,4,'$test$4',3),(5,5,'test...5',1),(6,6,'test6',6);
Query OK, 6 rows affected (0.02 sec)

mysql> insert into a_order values(1,1,'order中id为1',1),(2,2,'test_2',2),(3,3,'order中id为3',3),(4,4,'$order$4',4),(5,5,'order...5',1);
Query OK, 5 rows affected (0.02 sec)

mysql> select * from a_test a join (select * from a_order where pad>0) b  using(pad) order by a.id,b.id;
ERROR 1003 (HY000): field not found:b.pad
mysql> select * from a_test a join (select * from a_order where pad>0) b  using(pad) order by a.id,b.id;
ERROR 1003 (HY000): Illegal Capacity: -1

general.log

170908 18:33:25	  226 Query	SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ;
		  226 Query	select `a`.`pad`,`a`.`id`,`a`.`name`,`a`.`t_id` from  `a_test` `a`
		  199 Query	SET autocommit=1;
		  199 Query	select `a`.`pad`,`a`.`id`,`a`.`name`,`a`.`t_id` from  `a_test` `a`
		  223 Query	select `a_order`.`id` as `id`,`a_order`.`o_id` as `o_id`,`a_order`.`name` as `name` from  `a_order` where pad > 0
		  222 Query	SET autocommit=1;
		  222 Query	select `a_order`.`id` as `id`,`a_order`.`o_id` as `o_id`,`a_order`.`name` as `name` from  `a_order` where pad > 0

dble.log

2017-09-08 18:32:46.100  WARN [complexQueryExecutor108] (com.actiontech.dble.backend.mysql.nio.MySQLConnectionHandler.handleDataError(MySQLConnectionHandler.java:231)) - MySQLConnection [id=105, lastTime=1504866766083, user=test, schema=db1, old shema=db1, borrowed=true, fromSlaveDB=false, threadId=200, charset=utf8, txIsolation=3, autocommit=true, attachment=null, respHandler=com.actiontech.dble.backend.mysql.nio.handler.query.impl.BaseSelectHandler@230030d0, host=10.186.24.46, port=3306, statusSync=com.actiontech.dble.backend.mysql.nio.MySQLConnection$StatusSync@78f216da, writeQueue=0, modifiedSQLExecuted=false] handle data error:
com.actiontech.dble.plan.common.exception.MySQLOutPutException: field not found:b.pad
	at com.actiontech.dble.backend.mysql.nio.handler.util.HandlerTool.createFieldItem(HandlerTool.java:249) ~[dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.backend.mysql.nio.handler.util.HandlerTool.createItem(HandlerTool.java:101) ~[dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.backend.mysql.nio.handler.util.HandlerTool.createFunctionItem(HandlerTool.java:207) ~[dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.backend.mysql.nio.handler.util.HandlerTool.createItem(HandlerTool.java:85) ~[dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.backend.mysql.nio.handler.query.impl.WhereHandler.fieldEofResponse(WhereHandler.java:40) ~[dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.backend.mysql.nio.handler.query.impl.join.JoinHandler.fieldEofResponse(JoinHandler.java:99) ~[dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.backend.mysql.nio.handler.query.impl.SendMakeHandler.fieldEofResponse(SendMakeHandler.java:78) ~[dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.backend.mysql.nio.handler.query.impl.MultiNodeMergeHandler.fieldEofResponse(MultiNodeMergeHandler.java:105) ~[dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.backend.mysql.nio.handler.query.impl.BaseSelectHandler.fieldEofResponse(BaseSelectHandler.java:100) ~[dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.backend.mysql.nio.MySQLConnectionHandler.handleFieldEofPacket(MySQLConnectionHandler.java:192) ~[dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.backend.mysql.nio.MySQLConnectionHandler.handleData(MySQLConnectionHandler.java:118) [dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.net.handler.BackendAsyncHandler$1.run(BackendAsyncHandler.java:55) [dble-2.17.08.0-dev.jar:?]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110) [?:1.7.0_05]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603) [?:1.7.0_05]
	at java.lang.Thread.run(Thread.java:722) [?:1.7.0_05]
2017-09-08 18:34:26.524  WARN [Timer0] (com.actiontech.dble.net.NIOProcessor.backendCheck(NIOProcessor.java:219)) - found backend connection SQL timeout ,close it MySQLConnection [id=95, lastTime=1504865865543, user=test, schema=db2, old shema=db2, borrowed=true, fromSlaveDB=false, threadId=195, charset=utf8, txIsolation=3, autocommit=true, attachment=null, respHandler=SQLJob [ id=0,dataNodeOrDatabase=db2,sql=select user(),  jobHandler=com.actiontech.dble.sqlengine.OneRawSQLQueryResultHandler@6c6d07fa], host=10.186.24.46, port=3306, statusSync=null, writeQueue=0, modifiedSQLExecuted=false]
2017-09-08 18:35:01.332  WARN [complexQueryExecutor110] (com.actiontech.dble.backend.mysql.nio.MySQLConnectionHandler.handleDataError(MySQLConnectionHandler.java:231)) - MySQLConnection [id=105, lastTime=1504866901323, user=test, schema=db1, old shema=db1, borrowed=true, fromSlaveDB=false, threadId=200, charset=utf8, txIsolation=3, autocommit=true, attachment=dn2{select `a_order`.`id` as `id`,`a_order`.`o_id` as `o_id`,`a_order`.`name` as `name` from  `a_order` where pad > 0}.1, respHandler=com.actiontech.dble.backend.mysql.nio.handler.query.impl.BaseSelectHandler@177bb2da, host=10.186.24.46, port=3306, statusSync=com.actiontech.dble.backend.mysql.nio.MySQLConnection$StatusSync@78f216da, writeQueue=0, modifiedSQLExecuted=false] handle data error:
java.lang.IllegalArgumentException: Illegal Capacity: -1
	at java.util.ArrayList.<init>(ArrayList.java:130) ~[?:1.7.0_05]
	at com.actiontech.dble.net.mysql.RowDataPacket.<init>(RowDataPacket.java:67) ~[dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.backend.mysql.nio.handler.query.impl.BaseSelectHandler.rowResponse(BaseSelectHandler.java:107) ~[dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.backend.mysql.nio.MySQLConnectionHandler.handleRowPacket(MySQLConnectionHandler.java:204) ~[dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.backend.mysql.nio.MySQLConnectionHandler.handleData(MySQLConnectionHandler.java:135) [dble-2.17.08.0-dev.jar:?]
	at com.actiontech.dble.net.handler.BackendAsyncHandler$1.run(BackendAsyncHandler.java:55) [dble-2.17.08.0-dev.jar:?]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110) [?:1.7.0_05]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603) [?:1.7.0_05]
	at java.lang.Thread.run(Thread.java:722) [?:1.7.0_05]