[HIVE-20749] Constraints: Null scan optimizer does not remove entire TableScan

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 4.0.0
• Component/s: CBO, Logical Optimizer
• Assignee: Unassigned
• Reporter: Gopal Vijayaraghavan
• Created: 16/Oct/18 05:45
• Updated: 16/Oct/18 05:45

Description

With PK constraints on store table, the following query fails to remove the entire join (and cut the query short).

 explain select count(1) from store_sales, store where ss_store_sk = s_store_sk and s_store_sk is null and ss_sold_date_sk between 2450816 and 2450816+365;

Calcite generates the following optimized query, but the NullScan optimizer does not kick in for the query.

SELECT COUNT(*) AS `$f0`
FROM (SELECT *
FROM (SELECT 0 AS `DUMMY`
FROM `tpcds_bin_partitioned_orc_10000`.`store_sales`) AS `t`
WHERE FALSE) AS `t0`,
(SELECT *
FROM (SELECT 0 AS `DUMMY`
FROM `tpcds_bin_partitioned_orc_10000`.`store`) AS `t1`
WHERE FALSE) AS `t2`