[HAWQ-1339] Cache lookup failed after explain OLAP grouping query

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Fix Version/s: backlog
• Component/s: Catalog
• Assignee: Radar Da Lei
• Reporter: Amy Bai
• Created: 16/Feb/17 06:34
• Updated: 10/Jul/17 20:49

Description

Some OLAP grouping query may error out with "division by zero", and when do query explain, notice of "cache lookup failed for attribute 7 of relation 75036 (lsyscache.c:437)" occurred.

postgres=# SELECT sale.vn,sale.cn,sale.dt,GROUPING(sale.vn), TO_CHAR(COALESCE(MAX(DISTINCT floor(sale.vn+sale.qty)),0),'99999999.9999999'),TO_CHAR(COALESCE(VAR_SAMP(floor(sale.pn/sale.prc)),0),'99999999.9999999'),TO_CHAR(COALESCE(COUNT(floor(sale.qty+sale.prc)),0),'99999999.9999999')
postgres-# FROM sale,customer,vendor
postgres-# WHERE sale.cn=customer.cn AND sale.vn=vendor.vn
postgres-# GROUP BY ROLLUP((sale.prc),(sale.vn,sale.vn),(sale.pn,sale.pn),(sale.dt),(sale.qty,sale.vn,sale.qty)),ROLLUP((sale.pn),(sale.vn,sale.pn),(sale.qty)),(),sale.cn HAVING COALESCE(VAR_POP(sale.cn),0) >= 45.5839785564113;
ERROR:  division by zero  (seg0 localhost:40000 pid=25205)
postgres=#
postgres=# explain SELECT sale.vn,sale.cn,sale.dt,GROUPING(sale.vn), TO_CHAR(COALESCE(MAX(DISTINCT floor(sale.vn+sale.qty)),0),'99999999.9999999'),TO_CHAR(COALESCE(VAR_SAMP(floor(sale.pn/sale.prc)),0),'99999999.9999999'),TO_CHAR(COALESCE(COUNT(floor(sale.qty+sale.prc)),0),'99999999.9999999')
FROM sale,customer,vendor
WHERE sale.cn=customer.cn AND sale.vn=vendor.vn
GROUP BY ROLLUP((sale.prc),(sale.vn,sale.vn),(sale.pn,sale.pn),(sale.dt),(sale.qty,sale.vn,sale.qty)),ROLLUP((sale.pn),(sale.vn,sale.pn),(sale.qty)),(),sale.cn HAVING COALESCE(VAR_POP(sale.cn),0) >= 45.5839785564113;
NOTICE:  cache lookup failed for attribute 7 of relation 75036 (lsyscache.c:437)

The reproduction steps are:

Step 1: Prepare schema and data using attached olap_setup.sql

Step 2: Run below OLAP grouping query
-- OLAP query involving MAX() function
SELECT sale.vn,sale.cn,sale.dt,GROUPING(sale.vn), TO_CHAR(COALESCE(MAX(DISTINCT floor(sale.vn+sale.qty)),0),'99999999.9999999'),TO_CHAR(COALESCE(VAR_SAMP(floor(sale.pn/sale.prc)),0),'99999999.9999999'),TO_CHAR(COALESCE(COUNT(floor(sale.qty+sale.prc)),0),'99999999.9999999')
FROM sale,customer,vendor
WHERE sale.cn=customer.cn AND sale.vn=vendor.vn
GROUP BY ROLLUP((sale.prc),(sale.vn,sale.vn),(sale.pn,sale.pn),(sale.dt),(sale.qty,sale.vn,sale.qty)),ROLLUP((sale.pn),(sale.vn,sale.pn),(sale.qty)),(),sale.cn HAVING COALESCE(VAR_POP(sale.cn),0) >= 45.5839785564113;

explain SELECT sale.vn,sale.cn,sale.dt,GROUPING(sale.vn), TO_CHAR(COALESCE(MAX(DISTINCT floor(sale.vn+sale.qty)),0),'99999999.9999999'),TO_CHAR(COALESCE(VAR_SAMP(floor(sale.pn/sale.prc)),0),'99999999.9999999'),TO_CHAR(COALESCE(COUNT(floor(sale.qty+sale.prc)),0),'99999999.9999999')
FROM sale,customer,vendor
WHERE sale.cn=customer.cn AND sale.vn=vendor.vn
GROUP BY ROLLUP((sale.prc),(sale.vn,sale.vn),(sale.pn,sale.pn),(sale.dt),(sale.qty,sale.vn,sale.qty)),ROLLUP((sale.pn),(sale.vn,sale.pn),(sale.qty)),(),sale.cn HAVING COALESCE(VAR_POP(sale.cn),0) >= 45.5839785564113;