[FAQ Bot] NEW: Why does DuckDB show “IO Error: Could not set lock on file” after pressi

_questions/data-engineering-zoomcamp/general/001_d07a9a8ff9_duckdb-io-lock-suspend.md

@@ -0,0 +1,51 @@
+---
+id: d07a9a8ff9
+question: 'Why does DuckDB show “IO Error: Could not set lock on file” after pressing
+  Ctrl+Z in Ubuntu, and how can it be fixed?'
+sort_order: 1
+---
+
+Pressing `Ctrl+Z` while running:
+```
+duckdb data.duckdb
+```
+does not exit DuckDB.
+It only suspends the process and returns to the shell. The DuckDB process continues running in the background and still holds a lock on the database file.
+When running:
+```
+duckdb data.duckdb
+```
+gain, the message appears:
+```
+IO Error: Could not set lock on file
+```
+because the original suspended process still owns the file lock.
+How to fix it:
+* Option 1, resume and exit properly
+1. Bring the suspended process back to the foreground:
+```
+fg
+```
+2. Exit DuckDB properly:
+```
+.exit
+```
+or press:
+```
+Ctrl+D
+```
+* Option 2, kill the DuckDB process
+1. Check the running DuckDB process:
+```
+ps -Af | grep duckdb
+```
+Example output:
+```
+demo    33251    3667  0 08:21 pts/0    00:00:00 duckdb taxi_rides_ny.duckdb
+```
+The process ID (PID) is `33251`.
+2. Kill the process:
+```
+kill -9 33251
+```
+This releases the file lock.