int sqlite3VdbeCheckFk(Vdbe *p, int deferred){
  sqlite3 *db = p->db;
  if( (deferred && (db->nDeferredCons+db->nDeferredImmCons)>0) 
   || (!deferred && p->nFkConstraint>0) 
  ){
    p->rc = SQLITE_CONSTRAINT_FOREIGNKEY;
    p->errorAction = OE_Abort;
    sqlite3VdbeError(p, "FOREIGN KEY constraint failed");
    return SQLITE_ERROR;
  }
  return SQLITE_OK;
}