How do I notify a process of an SQLite database change done in a different process?

Question

Let\'s say I have two or more processes dealing with an SQLite database - a \"player\" process and many \"editor\" processes.

The \"player\" process reads the database

Answer 1

SQLite has an update_hook function which does what you want.

SQLite C Interface

Data Change Notification Callbacks

void *sqlite3_update_hook(
    sqlite3*,
    void(*)(void *,int ,char const *,char const *,sqlite3_int64),
    void*
);

The sqlite3_update_hook() interface registers a callback function with the database connection identified by the first argument to be invoked whenever a row is updated, inserted or deleted in a rowid table. Any callback set by a previous call to this function for the same database connection is overridden.

Unfortunately it isn't exposed by the Python sqlite module...

Here is a slightly hacky workaround that digs into the C api (from Python code) to make use of it: https://stackoverflow.com/a/16920926