[ https://issues.apache.org/jira/browse/IMPALA-2792?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Gabor Kaszab updated IMPALA-2792: --------------------------------- Labels: complextype nested_types planner ramp-up usability (was: nested_types planner ramp-up usability) > Syntactic sugar for computing aggregates over nested collections. > ----------------------------------------------------------------- > > Key: IMPALA-2792 > URL: https://issues.apache.org/jira/browse/IMPALA-2792 > Project: IMPALA > Issue Type: New Feature > Components: Frontend > Affects Versions: Impala 2.3.0 > Reporter: Alexander Behm > Priority: Major > Labels: complextype, nested_types, planner, ramp-up, usability > > For user convenience and SQL brevity, we should add syntax extensions to > concisely express aggregates over nested collections. Internally, we should > re-write the concise versions into the more verbose equivalent with a > correlated inline view. > Example A: > {code} > New syntax: > select count(c.orders) from customer c > Internally rewrite to: > select cnt from customer c, (select count(*) from c.orders) v > {code} > Example B: > {code} > New syntax: > select avg(c.orders.items.price) from customer c > Internally rewrite to: > select a from customer c, (select avg(price) from c.orders.items) v > {code} > I suggest performing the rewrite inside StmtRewriter.java after rewriting all > subqueries from the WHERE clause. > Similar syntactic improvements should be considered for analytic functions on > nested collections. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-all-unsubscr...@impala.apache.org For additional commands, e-mail: issues-all-h...@impala.apache.org