Obtain old.* Values From A Changeset Iterator

Obtain old.* Values From A Changeset Iterator

int sqlite3changeset_old(
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
  int iVal,                       /* Column number */
  sqlite3_value **ppValue         /* OUT: Old value (or NULL pointer) */
);

The pIter argument passed to this function may either be an iterator passed to a conflict-handler by sqlite3changeset_apply(), or an iterator created by sqlite3changeset_start(). In the latter case, the most recent call to sqlite3changeset_next() must have returned SQLITE_ROW. Furthermore, it may only be called if the type of change that the iterator currently points to is either SQLITE_DELETE or SQLITE_UPDATE. Otherwise, this function returns 登录查看完整内容