# Resolve a query memory limit error

A memory-limit error means a request exceeded its accounted SQL memory budget. Inspect both the effective setting and the workload before increasing that budget. The limit is distinct from total process memory and response-size limits.

```sql
SELECT name, value, "default"
FROM system.settings
WHERE name IN ('max_memory_usage', 'max_response_bytes')
FORMAT csv;
```

## Identify the expensive operation

Find the request's terminal event in `system.query_log` using its query identifier. Review peak memory, returned rows and the SQL text. If the statement sorts or groups a large input, narrow the input and projection. If the consumer requests a large export, split it into explicitly ordered ranges and verify every range.

`max_memory_usage` covers the request across its statements. Dividing one SQL batch into separate requests can change that scope, but it also changes transaction and temporary-table behavior.

## Change a ceiling deliberately

A server XML ceiling can only be tightened by a database setting. `SET max_memory_usage` persists for the selected database, requires autocommit with no active transactions there, and affects later requests. Zero removes only the additional database ceiling.

See [max_memory_usage](https://coordinatordb.com/docs/reference/settings/session-settings/max-memory-usage), [request limits](https://coordinatordb.com/docs/concepts/features/configuration/settings/query-complexity) and [query history](https://coordinatordb.com/docs/reference/system-tables/query-log).