[itroot]

I think that this applies to all modifying operations - INSERTs, UPDATEs, DELETEs.

It's perfectly ok to write to sqlite from different processes in the same time, but to achieve good results it's better to:

* use WAL mode - so the readers and writers do not block (you can turn on it with `PRAGMA journal_mode=WAL;` in CLI, and it's better to add `PRAGMA main.synchronous=NORMAL;` also).

* all concurrent writes will be queued by sqlite3 lib and done in sequential manner, and if any write attempt will wait longer that BUSY_TIMEOUT ( see https://www.sqlite.org/pragma.html#pragma_busy_timeout ) , it will return error.

Snippet

  # setting things up...
  itroot@l7490:/tmp$ grep -i pragma ~/.sqliterc
  PRAGMA journal_mode=WAL;
  PRAGMA main.synchronous=NORMAL;
  PRAGMA busy_timeout=1000;
  itroot@l7490:/tmp$ sqlite3 test.sqlite 'CREATE TABLE records (id INTEGER PRIMARY KEY, record TEXT);' > /dev/null 2>&1

  # running 10 parallel processes that inserts numbers from 1 to 1000...
  itroot@l7490:/tmp$ echo {1..1000} | xargs -n1 -d' ' -P 10 -i% sqlite3 test.sqlite 'INSERT INTO records (record) VALUES (%);' >/dev/null 2>&1

  # getting number of records
  itroot@l7490:/tmp$ sqlite3 test.sqlite 'SELECT count(*) FROM records;'
  count(*) = 1000