[ 
https://issues.apache.org/jira/browse/TAJO-939?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14060552#comment-14060552
 ] 

ASF GitHub Bot commented on TAJO-939:
-------------------------------------

Github user jihoonson commented on a diff in the pull request:

    https://github.com/apache/tajo/pull/71#discussion_r14873359
  
    --- Diff: 
tajo-core/src/test/java/org/apache/tajo/engine/planner/TestLogicalPlanPreprocessor.java
 ---
    @@ -0,0 +1,23 @@
    +/**
    + * Licensed to the Apache Software Foundation (ASF) under one
    + * or more contributor license agreements.  See the NOTICE file
    + * distributed with this work for additional information
    + * regarding copyright ownership.  The ASF licenses this file
    + * to you under the Apache License, Version 2.0 (the
    + * "License"); you may not use this file except in compliance
    + * with the License.  You may obtain a copy of the License at
    + *
    + *     http://www.apache.org/licenses/LICENSE-2.0
    + *
    + * Unless required by applicable law or agreed to in writing, software
    + * distributed under the License is distributed on an "AS IS" BASIS,
    + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    + * See the License for the specific language governing permissions and
    + * limitations under the License.
    + */
    +
    +package org.apache.tajo.engine.planner;
    +
    +
    +public class TestLogicalPlanPreprocessor {
    --- End diff --
    
    It seems that you intend to add some tests, but they are missed.


> Refactoring the column resolver in LogicalPlan
> ----------------------------------------------
>
>                 Key: TAJO-939
>                 URL: https://issues.apache.org/jira/browse/TAJO-939
>             Project: Tajo
>          Issue Type: Bug
>          Components: planner/optimizer
>            Reporter: Hyunsik Choi
>            Assignee: Hyunsik Choi
>             Fix For: 0.9.0
>
>
> The main role of the column resolver is to find the exact column in a 
> relation or a temporal column to which a variable name points. We have used a 
> monolithic column resolver to deal with lots of cases.
> But, resolving a name should play different roles according to at which the 
> name is placed. 
> For example, 1) a column name in select list always points one of fields in 
> relations, 2) a column name in WHERE clause can point to one of fields in 
> relations or one of aliased temporal fields in select list. If there are 
> duplicated, the column name firstly chooses the field in relations. 3) a 
> column name in ORDER BY clause is similar to that in WHERE clause, but it 
> firstly chooses one of aliased temporal fields in select list.
> The current column resolver does not consider the above rules. As a result, 
> it works incorrectly in some cases where a sql statement includes the same 
> name references, actually indicating one field in relation and one aliased 
> temporal field in select list. We should fix it.



--
This message was sent by Atlassian JIRA
(v6.2#6252)

Reply via email to