Logs

eMondrian writes logs that show what the server does — schema loading, the MDX and DAX it receives, and the SQL it sends to your database.

Where to find them

• Browser: http://localhost/logs/ (or http://<server-address>/logs/).
• Disk: the logs/ folder of the project. It is written by the container as root; deleting it needs sudo.

Files

File	Contents	Use it to
mondrian.log	Main server log: startup, schema loading, errors	Find schema errors, connection errors, license messages
mondrian-mdx.log	MDX queries received	See exactly what Excel or another client asked
mondrian-sql.log	SQL sent to your database, with timings	Understand performance, check joins and filters
mondrian-<date>-N.log, mondrian-sql-<date>-N.log, …	Older, rotated logs	Look back at earlier days
catalina.<date>.log	Application server (Tomcat) log	Startup problems of the server itself

Common tasks

Why doesn’t my catalog load? Open mondrian.log after a restart and search for the catalog or schema name — the error names the failing element.

Which SQL does a report send? Clear your view of mondrian-sql.log (note the last line), click through the report in Excel or Power BI, then read the new lines. Within a client session, repeated requests are served from cache and produce no new SQL.

Is the database the bottleneck? mondrian-sql.log shows timings per query. Slow SQL means: optimize the view, the table or the database; fast SQL with a slow report means the time is spent elsewhere.

From an AI agent: the MCP tool read_logs lists log files and shows the end of one (200 lines by default) — see AI agents (MCP).

Logs can contain data

Logs include queries and SQL, which may contain member names and filter values from your data. In Community, /logs/ is open to anyone who can reach the server — see Security.