[ https://issues.apache.org/jira/browse/ASTERIXDB-2913?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Michael J. Carey reassigned ASTERIXDB-2913: ------------------------------------------- Assignee: Dmitry Lychagin > Need "break up to make up" rewrite rule for unnested data > --------------------------------------------------------- > > Key: ASTERIXDB-2913 > URL: https://issues.apache.org/jira/browse/ASTERIXDB-2913 > Project: Apache AsterixDB > Issue Type: Bug > Reporter: Michael J. Carey > Assignee: Dmitry Lychagin > Priority: Major > > Consider the following query using the Don Chamberlin book data: > > _USE DonCData;_ > _WITH flat_orders AS (SELECT orderno, custid, order_date, ship_date FROM > orders),_ > _flat_items AS (SELECT o.orderno, i.* FROM orders o, o.items i)_ > _SELECT fo.*, fi.* FROM flat_orders fo, flat_items fi_ > _WHERE fo.orderno = fi.orderno;_ > Right now this query leads to two scans of orders - one for flat_orders and > one for flat_items - followed by a join of the two. > It seems like it should be possible to rewrite (under the hood) this query as > simply: > _USE DonCData;_ > _SELECT o.orderno, o.custid, o.order_date, o.ship_date, i.*_ > _FROM orders o, o.items i;_ > This capability could prove super-helpful in our future BI story. (Picture > two flat views being exported for JDBC - it would be nice to be able to piece > them back together for efficient querying under the hood.) -- This message was sent by Atlassian Jira (v8.3.4#803005)