tree b94efae1691f87639593ec04116c0bbb28126926
parent c3e84a5182acc6eec68fb0a121185332de616a5e
author Yingyi Bu <yingyi@couchbase.com> 1471244323 -0700
committer Yingyi Bu <buyingyi@gmail.com> 1471275896 -0700

Clean up GROUP BY and WITH clause.

- fix ASTERIXDB-971, i.e., the expression to plan translator for FLWOGR without a "for";
- fix the scoping for nested WITH clause;
- fix the scoping for nested GROUP BY clause;
- fix default fields in group variables;
- fix/unify the expression substition AST visitor;
- enhance RemoveUnusedAssignAndAggregateRule to be able to remove unused GROUP BY
  decoration varaibles;
- clearly sperate SQL++ aggregate functions and SQL-92 aggregate functions, i.e.,
  SQL-92 aggregate sugars cannot apply to SQL++ aggregate functions;
- fix PushAggregateIntoGroupbyRule for nested plan deletions;
- enhance RemoveCartesianProductWithEmptyBranchRule;
- add ExtractGroupByDecorVariablesRule;
- add an aggregate function first-element;
- fix ASTERIXDB-1560, an error message issue.

Change-Id: I62fca7f937aa007d97ed87c75cef19f6aa3e5ade
Reviewed-on: https://asterix-gerrit.ics.uci.edu/1050
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Integration-Tests: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Reviewed-by: Till Westmann <tillw@apache.org>