[ASTERIXDB-2468] Extend CountVarToCountOneRule to support no group-by - user model changes: no - storage format changes: no - interface changes: no
Details: - Extend CountVarToCountOneRule to support the no group-by case so that count queries without group-by can be handled as well. - Also extend this rule to support SQL_COUNT. In this case, count(v) is replaced with count(1) only v is not nullable.
[ASTERIXDB-2441][COMP] Improve column alias handling in ORDERBY/LIMIT - user model changes: no - storage format changes: no - interface changes: no
Details: - Introduce LET clauses for column alias expressions instead of inlining them into ORDER BY/LIMIT clauses - Fix incorrect visitor used in SubstituteGroupbyExpressionWithVariableVisitor for rewriting LET clauses after GROUP BY