Hyunsik Choi created TAJO-939:
---------------------------------
Summary: 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.
--
This message was sent by Atlassian JIRA
(v6.2#6252)
