This function causes any pending database operation to abort and return at its earliest opportunity. This routine is typically called in response to a user action such as pressing "Cancel" or Ctrl-C where the user wants a long query operation to halt immediately.
It is safe to call this routine from a thread different from the thread that is currently running the database operation. But it is not safe to call this routine with a database connection that is closed or might close before sqlite3_interrupt() returns.
If an SQL operation is very nearly finished at the time when sqlite3_interrupt() is called, then it might not have an opportunity to be interrupted and might continue to completion.
An SQL operation that is interrupted will return SQLITE_INTERRUPT. If the interrupted SQL operation is an INSERT, UPDATE, or DELETE that is inside an explicit transaction, then the entire transaction will be rolled back automatically.
The sqlite3_interrupt(D) call is in effect until all currently running SQL statements on database connection D complete. Any new SQL statements that are started after the sqlite3_interrupt() call and before the running statements reaches zero are interrupted as if they had been running prior to the sqlite3_interrupt() call. New SQL statements that are started after the running statement count reaches zero are not effected by the sqlite3_interrupt(). A call to sqlite3_interrupt(D) that occurs when there are no running SQL statements is a no-op and has no effect on SQL statements that are started after the sqlite3_interrupt() call returns.
If the database connection closes while sqlite3_interrupt() is running then bad things will likely happen.
*** DRAFT ***