/***********************************************************//**
Determines if it is possible to remove a secondary index entry.
Removal is possible if the secondary index entry does not refer to any
not delete marked version of a clustered index record where DB_TRX_ID
is newer than the purge view.
NOTE: This function should only be called by the purge thread, only
while holding a latch on the leaf page of the secondary index entry
(or keeping the buffer pool watch on the page). It is possible that
this function first returns TRUE and then FALSE, if a user transaction
inserts a record that the secondary index entry would refer to.
However, in that case, the user transaction would also re-insert the
secondary index entry after purge has removed it and released the leaf
page latch.
@return TRUE if the secondary index record can be purged */
UNIV_INTERN
ibool
row_purge_poss_sec(
/*===============*/
purge_node_t* node, /*!< in/out: row purge node */
dict_index_t* index, /*!< in: secondary index */
const dtuple_t* entry) /*!< in: secondary index entry */
{
ibool can_delete;
mtr_t mtr;
ut_ad(!dict_index_is_clust(index));
mtr_start(&mtr);
can_delete = !row_purge_reposition_pcur(BTR_SEARCH_LEAF, node, &mtr)
|| !row_vers_old_has_index_entry(TRUE,
btr_pcur_get_rec(&node->pcur),
&mtr, index, entry);
btr_pcur_commit_specify_mtr(&node->pcur, &mtr);
return(can_delete);
}
/***************************************************************
Removes a delete marked clustered index record if possible. */
static
ibool
row_purge_remove_clust_if_poss_low(
/*===============================*/
/* out: TRUE if success, or if not found, or
if modified after the delete marking */
purge_node_t* node, /* in: row purge node */
que_thr_t* thr, /* in: query thread */
ulint mode) /* in: BTR_MODIFY_LEAF or BTR_MODIFY_TREE */
{
dict_index_t* index;
btr_pcur_t* pcur;
btr_cur_t* btr_cur;
ibool success;
ulint err;
mtr_t mtr;
UT_NOT_USED(thr);
index = dict_table_get_first_index(node->table);
pcur = &(node->pcur);
btr_cur = btr_pcur_get_btr_cur(pcur);
mtr_start(&mtr);
success = row_purge_reposition_pcur(mode, node, &mtr);
if (!success) {
/* The record is already removed */
btr_pcur_commit_specify_mtr(pcur, &mtr);
return(TRUE);
}
if (0 != ut_dulint_cmp(node->roll_ptr,
row_get_rec_roll_ptr(btr_pcur_get_rec(pcur), index))) {
/* Someone else has modified the record later: do not remove */
btr_pcur_commit_specify_mtr(pcur, &mtr);
return(TRUE);
}
if (mode == BTR_MODIFY_LEAF) {
success = btr_cur_optimistic_delete(btr_cur, &mtr);
} else {
ut_ad(mode == BTR_MODIFY_TREE);
btr_cur_pessimistic_delete(&err, FALSE, btr_cur, FALSE, &mtr);
if (err == DB_SUCCESS) {
success = TRUE;
} else if (err == DB_OUT_OF_FILE_SPACE) {
success = FALSE;
} else {
ut_a(0);
}
}
btr_pcur_commit_specify_mtr(pcur, &mtr);
return(success);
}
/***********************************************************//**
Removes a delete marked clustered index record if possible.
@return TRUE if success, or if not found, or if modified after the
delete marking */
static
ibool
row_purge_remove_clust_if_poss_low(
/*===============================*/
purge_node_t* node, /*!< in: row purge node */
ulint mode) /*!< in: BTR_MODIFY_LEAF or BTR_MODIFY_TREE */
{
dict_index_t* index;
btr_pcur_t* pcur;
btr_cur_t* btr_cur;
ibool success;
ulint err;
mtr_t mtr;
rec_t* rec;
mem_heap_t* heap = NULL;
ulint offsets_[REC_OFFS_NORMAL_SIZE];
rec_offs_init(offsets_);
index = dict_table_get_first_index(node->table);
pcur = &(node->pcur);
btr_cur = btr_pcur_get_btr_cur(pcur);
log_free_check();
mtr_start(&mtr);
success = row_purge_reposition_pcur(mode, node, &mtr);
if (!success) {
/* The record is already removed */
btr_pcur_commit_specify_mtr(pcur, &mtr);
return(TRUE);
}
rec = btr_pcur_get_rec(pcur);
if (node->roll_ptr != row_get_rec_roll_ptr(
rec, index, rec_get_offsets(rec, index, offsets_,
ULINT_UNDEFINED, &heap))) {
if (UNIV_LIKELY_NULL(heap)) {
mem_heap_free(heap);
}
/* Someone else has modified the record later: do not remove */
btr_pcur_commit_specify_mtr(pcur, &mtr);
return(TRUE);
}
if (UNIV_LIKELY_NULL(heap)) {
mem_heap_free(heap);
}
if (mode == BTR_MODIFY_LEAF) {
success = btr_cur_optimistic_delete(btr_cur, &mtr);
} else {
ut_ad(mode == BTR_MODIFY_TREE);
btr_cur_pessimistic_delete(&err, FALSE, btr_cur,
RB_NONE, &mtr);
if (err == DB_SUCCESS) {
success = TRUE;
} else if (err == DB_OUT_OF_FILE_SPACE) {
success = FALSE;
} else {
ut_error;
}
}
btr_pcur_commit_specify_mtr(pcur, &mtr);
return(success);
}
/***************************************************************
Removes a secondary index entry if possible. */
static
ibool
row_purge_remove_sec_if_poss_low(
/*=============================*/
/* out: TRUE if success or if not found */
purge_node_t* node, /* in: row purge node */
que_thr_t* thr, /* in: query thread */
dict_index_t* index, /* in: index */
dtuple_t* entry, /* in: index entry */
ulint mode) /* in: latch mode BTR_MODIFY_LEAF or
BTR_MODIFY_TREE */
{
btr_pcur_t pcur;
btr_cur_t* btr_cur;
ibool success;
ibool old_has;
ibool found;
ulint err;
mtr_t mtr;
mtr_t* mtr_vers;
UT_NOT_USED(thr);
log_free_check();
mtr_start(&mtr);
found = row_search_index_entry(index, entry, mode, &pcur, &mtr);
if (!found) {
/* Not found */
/* printf("PURGE:........sec entry not found\n"); */
/* dtuple_print(entry); */
btr_pcur_close(&pcur);
mtr_commit(&mtr);
return(TRUE);
}
btr_cur = btr_pcur_get_btr_cur(&pcur);
/* We should remove the index record if no later version of the row,
which cannot be purged yet, requires its existence. If some requires,
we should do nothing. */
mtr_vers = mem_alloc(sizeof(mtr_t));
mtr_start(mtr_vers);
success = row_purge_reposition_pcur(BTR_SEARCH_LEAF, node, mtr_vers);
if (success) {
old_has = row_vers_old_has_index_entry(TRUE,
btr_pcur_get_rec(&(node->pcur)),
mtr_vers, index, entry);
}
btr_pcur_commit_specify_mtr(&(node->pcur), mtr_vers);
mem_free(mtr_vers);
if (!success || !old_has) {
/* Remove the index record */
if (mode == BTR_MODIFY_LEAF) {
success = btr_cur_optimistic_delete(btr_cur, &mtr);
} else {
ut_ad(mode == BTR_MODIFY_TREE);
btr_cur_pessimistic_delete(&err, FALSE, btr_cur,
FALSE, &mtr);
if (err == DB_SUCCESS) {
success = TRUE;
} else if (err == DB_OUT_OF_FILE_SPACE) {
success = FALSE;
} else {
ut_a(0);
}
}
}
btr_pcur_close(&pcur);
mtr_commit(&mtr);
return(success);
}
