rc_t bt_cursor_t::_check_page_update(btree_page_h &p)
{
// was the page changed?
if (_pid != p.pid() || p.get_page_lsn() != _lsn) {
// check if the page still contains the key we are based on
bool found = false;
if (p.fence_contains(_key)) {
// it still contains. just re-locate _slot
p.search(_key, found, _slot);
} else {
// we have to re-locate the page
W_DO( btree_impl::_ux_traverse(_store, _key, btree_impl::t_fence_contain, LATCH_SH, p));
p.search(_key, found, _slot);
}
w_assert1(found || !_needs_lock
|| (!_forward && !_upper_inclusive && !_dont_move_next)); // see _locate_first
_set_current_page(p);
}
return RCOK;
}
rc_t btree_impl::_sx_split_if_needed (btree_page_h &page, const w_keystr_t &new_key) {
bool need_split =
!page.check_space_for_insert_node(new_key)
|| (page.is_insertion_extremely_skewed_right()
&& page.check_chance_for_norecord_split(new_key));
if (!need_split) {
return RCOK; // easy
}
PageID new_page_id;
// we are running user transaction. simply call SSX split.
W_DO(_sx_split_foster(page, new_page_id, new_key));
// After split, the new page might be the parent of the new_key now.
if (!page.fence_contains(new_key)) {
btree_page_h new_page;
W_DO(new_page.fix_nonroot(page, new_page_id, LATCH_EX));
w_assert1(new_page.fence_contains(new_key));
page.unfix();
page = new_page;
}
return RCOK;
}
