Set full CBO debug output in a session
Details
| Detail name | Value |
|---|---|
| Changelog Number | 27974 |
| Type | New Feature |
| Status | Resolved |
| Fix Versions | Exasol 2025.2.0, Exasol 2025.1.9 |
| Resolution Date | 2025-12-17 |
Background
It is often essential to get extended information about the cost based optimizer to debug problems.
However, the information can grow large pretty quickly so it is not an option to enable the extended log output for a full database in production.
New Feature
It is now possible to set the extended log output in a session:
CONTROL SET TRACE CBO=0; sets no output (default).
CONTROL SET TRACE CBO=1; gives extensive input/output details.
CONTROL SET TRACE CBO=2; prints every CBO step.
As the output is extremely large, only users with DBA role can use the new command.
Changed behavior
The command line parameter -tracecbo is no longer available.
