Alexander Klimetschek created OAK-4888:
------------------------------------------
Summary: Warn or fail queries above a configurable cost value
Key: OAK-4888
URL: https://issues.apache.org/jira/browse/OAK-4888
Project: Jackrabbit Oak
Issue Type: Improvement
Components: query
Reporter: Alexander Klimetschek
*Problem:* It's easy to run into performance problems with queries that are not
backed by an index or miss the right one. Developers writing these queries
typically do not have the real large production data, and thus don't see that a
query would scale badly, and would not see any traversal warnings, as these
only happen with a large number of results.
*Proposal:* Oak's query engine already calculates a cost estimate to make a
decision which index to use, or even if there is any at all. This cost estimate
could be used to find out if a query is not supported by an index or with one
that is not suitable enough (e.g. ordering by property that is not indexed)
If a query is above cost value, a big warning could be put out or even the
query could be made to fail (maybe a per query option, that you might want to
have to "fail" by default to ensure people are not missing the problem). The
cost limit should be configurable, as it might depend on the hardware power.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
