This article provides guidance for troubleshooting the following error seen when using the Pivotal Query Optimizer (PQO) also known as ORCA in either Pivotal Greenplum or Pivotal HDB.
2017-02-02 20:00:42:638492 JST,THD000,ERROR,""CErrorHandlerStandard.cpp:75: No plan has been computed for required properties"",",,,,,,"select XXXX,"COptTasks.cpp",555,
The above error would be seen in the master log.
The error means that the PQO could not compute a plan for the query. PQO is still actively developed and frequently improved and it is the expected behaviour that we fall back to the Legacy planner when PQO can't perform an operation or find a suitable plan for a given query.
Although there isn't any permanent fix for this yet except falling back to the Legacy planner, the following information would be helpful for our development team in order to continue improving the PQO:
A. Does the query return results even if you see this error?
B. Collect an EXPLAIN and EXPLAIN ANALYZE output for the affected query.
C. Collect an Optimizer Minidump File generated by the affected query. The minidump files describes the optimisation context for a given query and helps us analyse query optimizer problems. To collect the minidump, you can follow the steps below:
- Login into the database via PSQL:
- Enable the Optimizer Minidump generation on a session level:
set optimizer_minidump = always
- Run the affected query:
select column from table where...
- Exit PSQL:
- Collect the .mdp file that was generated in the master data directory: