ibool
row_upd_changes_some_index_ord_field_binary(
/*========================================*/
/* out: TRUE if update vector may change
an ordering field in an index record */
dict_table_t* table, /* in: table */
upd_t* update) /* in: update vector for the row */
{
upd_field_t* upd_field;
dict_index_t* index;
ulint i;
index = dict_table_get_first_index(table);
for (i = 0; i < upd_get_n_fields(update); i++) {
upd_field = upd_get_nth_field(update, i);
if (dict_field_get_col(dict_index_get_nth_field(index,
upd_field->field_no))
->ord_part) {
return(TRUE);
}
}
return(FALSE);
}
void
row_upd_clust_index_replace_new_col_vals(
/*=====================================*/
dtuple_t* entry, /* in/out: index entry where replaced */
upd_t* update) /* in: update vector */
{
upd_field_t* upd_field;
dfield_t* dfield;
dfield_t* new_val;
ulint field_no;
ulint i;
dtuple_set_info_bits(entry, update->info_bits);
for (i = 0; i < upd_get_n_fields(update); i++) {
upd_field = upd_get_nth_field(update, i);
field_no = upd_field->field_no;
dfield = dtuple_get_nth_field(entry, field_no);
new_val = &(upd_field->new_val);
dfield_set_data(dfield, new_val->data, new_val->len);
}
}
upd_t*
row_upd_build_sec_rec_difference_binary(
/*====================================*/
/* out, own: update vector of differing
fields */
dict_index_t* index, /* in: index */
dtuple_t* entry, /* in: entry to insert */
rec_t* rec, /* in: secondary index record */
mem_heap_t* heap) /* in: memory heap from which allocated */
{
upd_field_t* upd_field;
dfield_t* dfield;
byte* data;
ulint len;
upd_t* update;
ulint n_diff;
ulint i;
/* This function is used only for a secondary index */
ut_ad(0 == (index->type & DICT_CLUSTERED));
update = upd_create(dtuple_get_n_fields(entry), heap);
n_diff = 0;
for (i = 0; i < dtuple_get_n_fields(entry); i++) {
data = rec_get_nth_field(rec, i, &len);
dfield = dtuple_get_nth_field(entry, i);
ut_a(len == dfield_get_len(dfield));
/* NOTE: we compare the fields as binary strings!
(No collation) */
if (!dfield_data_is_binary_equal(dfield, len, data)) {
upd_field = upd_get_nth_field(update, n_diff);
dfield_copy(&(upd_field->new_val), dfield);
upd_field_set_field_no(upd_field, i, index);
upd_field->extern_storage = FALSE;
n_diff++;
}
}
update->n_fields = n_diff;
return(update);
}
ibool
row_upd_changes_ord_field_binary(
/*=============================*/
/* out: TRUE if update vector changes
an ordering field in the index record;
NOTE: the fields are compared as binary
strings */
dtuple_t* row, /* in: old value of row, or NULL if the
row and the data values in update are not
known when this function is called, e.g., at
compile time */
dict_index_t* index, /* in: index of the record */
upd_t* update) /* in: update vector for the row */
{
upd_field_t* upd_field;
dict_field_t* ind_field;
dict_col_t* col;
ulint n_unique;
ulint n_upd_fields;
ulint col_pos;
ulint col_no;
ulint i, j;
ut_ad(update && index);
n_unique = dict_index_get_n_unique(index);
n_upd_fields = upd_get_n_fields(update);
for (i = 0; i < n_unique; i++) {
ind_field = dict_index_get_nth_field(index, i);
col = dict_field_get_col(ind_field);
col_pos = dict_col_get_clust_pos(col);
col_no = dict_col_get_no(col);
for (j = 0; j < n_upd_fields; j++) {
upd_field = upd_get_nth_field(update, j);
if (col_pos == upd_field->field_no
&& (row == NULL
|| !dfield_datas_are_binary_equal(
dtuple_get_nth_field(row, col_no),
&(upd_field->new_val)))) {
return(TRUE);
}
}
}
return(FALSE);
}
ibool
row_upd_changes_field_size(
/*=======================*/
/* out: TRUE if the update changes the size of
some field in index */
rec_t* rec, /* in: record in clustered index */
dict_index_t* index, /* in: clustered index */
upd_t* update) /* in: update vector */
{
upd_field_t* upd_field;
dfield_t* new_val;
ulint old_len;
ulint new_len;
ulint n_fields;
ulint i;
ut_ad(index->type & DICT_CLUSTERED);
n_fields = upd_get_n_fields(update);
for (i = 0; i < n_fields; i++) {
upd_field = upd_get_nth_field(update, i);
new_val = &(upd_field->new_val);
new_len = new_val->len;
if (new_len == UNIV_SQL_NULL) {
new_len = dtype_get_sql_null_size(
dict_index_get_nth_type(index, i));
}
old_len = rec_get_nth_field_size(rec, upd_field->field_no);
if (old_len != new_len) {
return(TRUE);
}
if (rec_get_nth_field_extern_bit(rec, upd_field->field_no)) {
return(TRUE);
}
if (upd_field->extern_storage) {
return(TRUE);
}
}
return(FALSE);
}
/*************************************************************************
Calculates the new values for fields to update. Note that row_upd_copy_columns
must have been called first. */
UNIV_INLINE
void
row_upd_eval_new_vals(
/*==================*/
upd_t* update) /* in: update vector */
{
que_node_t* exp;
upd_field_t* upd_field;
ulint n_fields;
ulint i;
n_fields = upd_get_n_fields(update);
for (i = 0; i < n_fields; i++) {
upd_field = upd_get_nth_field(update, i);
exp = upd_field->exp;
eval_exp(exp);
dfield_copy_data(&(upd_field->new_val), que_node_get_val(exp));
}
}
void
row_upd_index_replace_new_col_vals(
/*===============================*/
dtuple_t* entry, /* in/out: index entry where replaced */
dict_index_t* index, /* in: index; NOTE that may also be a
non-clustered index */
upd_t* update) /* in: update vector */
{
upd_field_t* upd_field;
dfield_t* dfield;
dfield_t* new_val;
ulint field_no;
dict_index_t* clust_index;
ulint i;
ut_ad(index);
clust_index = dict_table_get_first_index(index->table);
dtuple_set_info_bits(entry, update->info_bits);
for (i = 0; i < upd_get_n_fields(update); i++) {
upd_field = upd_get_nth_field(update, i);
field_no = dict_index_get_nth_col_pos(index,
dict_index_get_nth_col_no(clust_index,
upd_field->field_no));
if (field_no != ULINT_UNDEFINED) {
dfield = dtuple_get_nth_field(entry, field_no);
new_val = &(upd_field->new_val);
dfield_set_data(dfield, new_val->data, new_val->len);
}
}
}
void
row_upd_rec_in_place(
/*=================*/
rec_t* rec, /* in/out: record where replaced */
upd_t* update) /* in: update vector */
{
upd_field_t* upd_field;
dfield_t* new_val;
ulint n_fields;
ulint i;
rec_set_info_bits(rec, update->info_bits);
n_fields = upd_get_n_fields(update);
for (i = 0; i < n_fields; i++) {
upd_field = upd_get_nth_field(update, i);
new_val = &(upd_field->new_val);
rec_set_nth_field(rec, upd_field->field_no,
dfield_get_data(new_val),
dfield_get_len(new_val));
}
}
upd_t*
row_upd_build_difference_binary(
/*============================*/
/* out, own: update vector of differing
fields, excluding roll ptr and trx id */
dict_index_t* index, /* in: clustered index */
dtuple_t* entry, /* in: entry to insert */
ulint* ext_vec,/* in: array containing field numbers of
externally stored fields in entry, or NULL */
ulint n_ext_vec,/* in: number of fields in ext_vec */
rec_t* rec, /* in: clustered index record */
mem_heap_t* heap) /* in: memory heap from which allocated */
{
upd_field_t* upd_field;
dfield_t* dfield;
byte* data;
ulint len;
upd_t* update;
ulint n_diff;
ulint roll_ptr_pos;
ulint trx_id_pos;
ulint i;
/* This function is used only for a clustered index */
ut_a(index->type & DICT_CLUSTERED);
update = upd_create(dtuple_get_n_fields(entry), heap);
n_diff = 0;
roll_ptr_pos = dict_index_get_sys_col_pos(index, DATA_ROLL_PTR);
trx_id_pos = dict_index_get_sys_col_pos(index, DATA_TRX_ID);
for (i = 0; i < dtuple_get_n_fields(entry); i++) {
data = rec_get_nth_field(rec, i, &len);
dfield = dtuple_get_nth_field(entry, i);
/* NOTE: we compare the fields as binary strings!
(No collation) */
if (i == trx_id_pos || i == roll_ptr_pos) {
goto skip_compare;
}
if (rec_get_nth_field_extern_bit(rec, i)
!= upd_ext_vec_contains(ext_vec, n_ext_vec, i)
|| !dfield_data_is_binary_equal(dfield, len, data)) {
upd_field = upd_get_nth_field(update, n_diff);
dfield_copy(&(upd_field->new_val), dfield);
upd_field_set_field_no(upd_field, i, index);
if (upd_ext_vec_contains(ext_vec, n_ext_vec, i)) {
upd_field->extern_storage = TRUE;
} else {
upd_field->extern_storage = FALSE;
}
n_diff++;
}
skip_compare:
;
}
update->n_fields = n_diff;
return(update);
}
/***************************************************************
Purges an update of an existing record. Also purges an update of a delete
marked record if that record contained an externally stored field. */
static
void
row_purge_upd_exist_or_extern(
/*==========================*/
purge_node_t* node, /* in: row purge node */
que_thr_t* thr) /* in: query thread */
{
mem_heap_t* heap;
dtuple_t* entry;
dict_index_t* index;
upd_field_t* ufield;
ibool is_insert;
ulint rseg_id;
ulint page_no;
ulint offset;
ulint internal_offset;
byte* data_field;
ulint data_field_len;
ulint i;
mtr_t mtr;
ut_ad(node && thr);
if (node->rec_type == TRX_UNDO_UPD_DEL_REC) {
goto skip_secondaries;
}
heap = mem_heap_create(1024);
while (node->index != NULL) {
index = node->index;
if (row_upd_changes_ord_field_binary(NULL, node->index,
node->update)) {
/* Build the older version of the index entry */
entry = row_build_index_entry(node->row, index, heap);
row_purge_remove_sec_if_poss(node, thr, index, entry);
}
node->index = dict_table_get_next_index(node->index);
}
mem_heap_free(heap);
skip_secondaries:
/* Free possible externally stored fields */
for (i = 0; i < upd_get_n_fields(node->update); i++) {
ufield = upd_get_nth_field(node->update, i);
if (ufield->extern_storage) {
/* We use the fact that new_val points to
node->undo_rec and get thus the offset of
dfield data inside the unod record. Then we
can calculate from node->roll_ptr the file
address of the new_val data */
internal_offset = ((byte*)ufield->new_val.data)
- node->undo_rec;
ut_a(internal_offset < UNIV_PAGE_SIZE);
trx_undo_decode_roll_ptr(node->roll_ptr,
&is_insert, &rseg_id,
&page_no, &offset);
mtr_start(&mtr);
/* We have to acquire an X-latch to the clustered
index tree */
index = dict_table_get_first_index(node->table);
mtr_x_lock(dict_tree_get_lock(index->tree), &mtr);
/* We assume in purge of externally stored fields
that the space id of the undo log record is 0! */
data_field = buf_page_get(0, page_no, RW_X_LATCH, &mtr)
+ offset + internal_offset;
buf_page_dbg_add_level(buf_frame_align(data_field),
SYNC_TRX_UNDO_PAGE);
data_field_len = ufield->new_val.len;
btr_free_externally_stored_field(index, data_field,
data_field_len, FALSE, &mtr);
mtr_commit(&mtr);
}
}
}
byte*
row_upd_index_parse(
/*================*/
/* out: log data end or NULL */
byte* ptr, /* in: buffer */
byte* end_ptr,/* in: buffer end */
mem_heap_t* heap, /* in: memory heap where update vector is
built */
upd_t** update_out)/* out: update vector */
{
upd_t* update;
upd_field_t* upd_field;
dfield_t* new_val;
ulint len;
ulint n_fields;
byte* buf;
ulint info_bits;
ulint i;
if (end_ptr < ptr + 1) {
return(NULL);
}
info_bits = mach_read_from_1(ptr);
ptr++;
ptr = mach_parse_compressed(ptr, end_ptr, &n_fields);
if (ptr == NULL) {
return(NULL);
}
update = upd_create(n_fields, heap);
update->info_bits = info_bits;
for (i = 0; i < n_fields; i++) {
upd_field = upd_get_nth_field(update, i);
new_val = &(upd_field->new_val);
ptr = mach_parse_compressed(ptr, end_ptr,
&(upd_field->field_no));
if (ptr == NULL) {
return(NULL);
}
ptr = mach_parse_compressed(ptr, end_ptr, &len);
if (ptr == NULL) {
return(NULL);
}
new_val->len = len;
if (len != UNIV_SQL_NULL) {
if (end_ptr < ptr + len) {
return(NULL);
} else {
buf = mem_heap_alloc(heap, len);
ut_memcpy(buf, ptr, len);
ptr += len;
new_val->data = buf;
}
}
}
*update_out = update;
return(ptr);
}
void
row_upd_index_write_log(
/*====================*/
upd_t* update, /* in: update vector */
byte* log_ptr,/* in: pointer to mlog buffer: must contain at least
MLOG_BUF_MARGIN bytes of free space; the buffer is
closed within this function */
mtr_t* mtr) /* in: mtr into whose log to write */
{
upd_field_t* upd_field;
dfield_t* new_val;
ulint len;
ulint n_fields;
byte* buf_end;
ulint i;
n_fields = upd_get_n_fields(update);
buf_end = log_ptr + MLOG_BUF_MARGIN;
mach_write_to_1(log_ptr, update->info_bits);
log_ptr++;
log_ptr += mach_write_compressed(log_ptr, n_fields);
for (i = 0; i < n_fields; i++) {
ut_ad(MLOG_BUF_MARGIN > 30);
if (log_ptr + 30 > buf_end) {
mlog_close(mtr, log_ptr);
log_ptr = mlog_open(mtr, MLOG_BUF_MARGIN);
buf_end = log_ptr + MLOG_BUF_MARGIN;
}
upd_field = upd_get_nth_field(update, i);
new_val = &(upd_field->new_val);
len = new_val->len;
log_ptr += mach_write_compressed(log_ptr, upd_field->field_no);
log_ptr += mach_write_compressed(log_ptr, len);
if (len != UNIV_SQL_NULL) {
if (log_ptr + len < buf_end) {
ut_memcpy(log_ptr, new_val->data, len);
log_ptr += len;
} else {
mlog_close(mtr, log_ptr);
mlog_catenate_string(mtr, new_val->data, len);
log_ptr = mlog_open(mtr, MLOG_BUF_MARGIN);
buf_end = log_ptr + MLOG_BUF_MARGIN;
}
}
}
mlog_close(mtr, log_ptr);
}
/**************************************************************************
Reports in the undo log of an update or delete marking of a clustered index
record. */
static
ulint
trx_undo_page_report_modify(
/*========================*/
/* out: byte offset of the inserted
undo log entry on the page if succeed,
0 if fail */
page_t* undo_page, /* in: undo log page */
trx_t* trx, /* in: transaction */
dict_index_t* index, /* in: clustered index where update or
delete marking is done */
rec_t* rec, /* in: clustered index record which
has NOT yet been modified */
const ulint* offsets, /* in: rec_get_offsets(rec, index) */
upd_t* update, /* in: update vector which tells the
columns to be updated; in the case of
a delete, this should be set to NULL */
ulint cmpl_info, /* in: compiler info on secondary
index updates */
mtr_t* mtr) /* in: mtr */
{
dict_table_t* table;
upd_field_t* upd_field;
ulint first_free;
byte* ptr;
ulint len;
byte* field;
ulint flen;
ulint pos;
dulint roll_ptr;
dulint trx_id;
ulint bits;
ulint col_no;
byte* old_ptr;
ulint type_cmpl;
byte* type_cmpl_ptr;
ulint i;
ut_a(index->type & DICT_CLUSTERED);
ut_ad(rec_offs_validate(rec, index, offsets));
ut_ad(mach_read_from_2(undo_page + TRX_UNDO_PAGE_HDR
+ TRX_UNDO_PAGE_TYPE) == TRX_UNDO_UPDATE);
table = index->table;
first_free = mach_read_from_2(undo_page + TRX_UNDO_PAGE_HDR
+ TRX_UNDO_PAGE_FREE);
ptr = undo_page + first_free;
ut_ad(first_free <= UNIV_PAGE_SIZE);
if (trx_undo_left(undo_page, ptr) < 50) {
/* NOTE: the value 50 must be big enough so that the general
fields written below fit on the undo log page */
return(0);
}
/* Reserve 2 bytes for the pointer to the next undo log record */
ptr += 2;
/* Store first some general parameters to the undo log */
if (update) {
if (rec_get_deleted_flag(rec, dict_table_is_comp(table))) {
type_cmpl = TRX_UNDO_UPD_DEL_REC;
} else {
type_cmpl = TRX_UNDO_UPD_EXIST_REC;
}
} else {
type_cmpl = TRX_UNDO_DEL_MARK_REC;
}
type_cmpl = type_cmpl | (cmpl_info * TRX_UNDO_CMPL_INFO_MULT);
mach_write_to_1(ptr, type_cmpl);
type_cmpl_ptr = ptr;
ptr++;
len = mach_dulint_write_much_compressed(ptr, trx->undo_no);
ptr += len;
len = mach_dulint_write_much_compressed(ptr, table->id);
ptr += len;
/*----------------------------------------*/
/* Store the state of the info bits */
bits = rec_get_info_bits(rec, dict_table_is_comp(table));
mach_write_to_1(ptr, bits);
ptr += 1;
/* Store the values of the system columns */
field = rec_get_nth_field(rec, offsets,
dict_index_get_sys_col_pos(
index, DATA_TRX_ID), &len);
ut_ad(len == DATA_TRX_ID_LEN);
trx_id = trx_read_trx_id(field);
field = rec_get_nth_field(rec, offsets,
dict_index_get_sys_col_pos(
index, DATA_ROLL_PTR), &len);
ut_ad(len == DATA_ROLL_PTR_LEN);
roll_ptr = trx_read_roll_ptr(field);
len = mach_dulint_write_compressed(ptr, trx_id);
ptr += len;
len = mach_dulint_write_compressed(ptr, roll_ptr);
ptr += len;
/*----------------------------------------*/
/* Store then the fields required to uniquely determine the
record which will be modified in the clustered index */
for (i = 0; i < dict_index_get_n_unique(index); i++) {
field = rec_get_nth_field(rec, offsets, i, &flen);
if (trx_undo_left(undo_page, ptr) < 4) {
return(0);
}
len = mach_write_compressed(ptr, flen);
ptr += len;
if (flen != UNIV_SQL_NULL) {
if (trx_undo_left(undo_page, ptr) < flen) {
return(0);
}
ut_memcpy(ptr, field, flen);
ptr += flen;
}
}
/*----------------------------------------*/
/* Save to the undo log the old values of the columns to be updated. */
if (update) {
if (trx_undo_left(undo_page, ptr) < 5) {
return(0);
}
len = mach_write_compressed(ptr, upd_get_n_fields(update));
ptr += len;
for (i = 0; i < upd_get_n_fields(update); i++) {
upd_field = upd_get_nth_field(update, i);
pos = upd_field->field_no;
/* Write field number to undo log */
if (trx_undo_left(undo_page, ptr) < 5) {
return(0);
}
len = mach_write_compressed(ptr, pos);
ptr += len;
/* Save the old value of field */
field = rec_get_nth_field(rec, offsets, pos, &flen);
if (trx_undo_left(undo_page, ptr) < 5) {
return(0);
}
if (rec_offs_nth_extern(offsets, pos)) {
/* If a field has external storage, we add
to flen the flag */
len = mach_write_compressed(
ptr,
UNIV_EXTERN_STORAGE_FIELD + flen);
/* Notify purge that it eventually has to
free the old externally stored field */
trx->update_undo->del_marks = TRUE;
*type_cmpl_ptr = *type_cmpl_ptr
| TRX_UNDO_UPD_EXTERN;
} else {
len = mach_write_compressed(ptr, flen);
}
ptr += len;
if (flen != UNIV_SQL_NULL) {
if (trx_undo_left(undo_page, ptr) < flen) {
return(0);
}
ut_memcpy(ptr, field, flen);
ptr += flen;
}
}
}
/*----------------------------------------*/
/* In the case of a delete marking, and also in the case of an update
where any ordering field of any index changes, store the values of all
columns which occur as ordering fields in any index. This info is used
in the purge of old versions where we use it to build and search the
delete marked index records, to look if we can remove them from the
index tree. Note that starting from 4.0.14 also externally stored
fields can be ordering in some index. But we always store at least
384 first bytes locally to the clustered index record, which means
we can construct the column prefix fields in the index from the
stored data. */
if (!update || !(cmpl_info & UPD_NODE_NO_ORD_CHANGE)) {
trx->update_undo->del_marks = TRUE;
if (trx_undo_left(undo_page, ptr) < 5) {
return(0);
}
old_ptr = ptr;
/* Reserve 2 bytes to write the number of bytes the stored
fields take in this undo record */
ptr += 2;
for (col_no = 0; col_no < dict_table_get_n_cols(table);
col_no++) {
const dict_col_t* col
= dict_table_get_nth_col(table, col_no);
if (col->ord_part > 0) {
pos = dict_index_get_nth_col_pos(index,
col_no);
/* Write field number to undo log */
if (trx_undo_left(undo_page, ptr) < 5) {
return(0);
}
len = mach_write_compressed(ptr, pos);
ptr += len;
/* Save the old value of field */
field = rec_get_nth_field(rec, offsets, pos,
&flen);
if (trx_undo_left(undo_page, ptr) < 5) {
return(0);
}
len = mach_write_compressed(ptr, flen);
ptr += len;
if (flen != UNIV_SQL_NULL) {
if (trx_undo_left(undo_page, ptr)
< flen) {
return(0);
}
ut_memcpy(ptr, field, flen);
ptr += flen;
}
}
}
mach_write_to_2(old_ptr, ptr - old_ptr);
}
/*----------------------------------------*/
/* Write pointers to the previous and the next undo log records */
if (trx_undo_left(undo_page, ptr) < 2) {
return(0);
}
mach_write_to_2(ptr, first_free);
ptr += 2;
mach_write_to_2(undo_page + first_free, ptr - undo_page);
mach_write_to_2(undo_page + TRX_UNDO_PAGE_HDR + TRX_UNDO_PAGE_FREE,
ptr - undo_page);
/* Write to the REDO log about this change in the UNDO log */
trx_undof_page_add_undo_rec_log(undo_page, first_free,
ptr - undo_page, mtr);
return(first_free);
}
/***********************************************************//**
Purges an update of an existing record. Also purges an update of a delete
marked record if that record contained an externally stored field. */
static
void
row_purge_upd_exist_or_extern_func(
/*===============================*/
#ifdef UNIV_DEBUG
const que_thr_t*thr, /*!< in: query thread */
#endif /* UNIV_DEBUG */
purge_node_t* node) /*!< in: row purge node */
{
mem_heap_t* heap;
dtuple_t* entry;
dict_index_t* index;
ibool is_insert;
ulint rseg_id;
ulint page_no;
ulint offset;
ulint i;
mtr_t mtr;
ut_ad(node);
if (node->rec_type == TRX_UNDO_UPD_DEL_REC
|| (node->cmpl_info & UPD_NODE_NO_ORD_CHANGE)) {
goto skip_secondaries;
}
heap = mem_heap_create(1024);
while (node->index != NULL) {
dict_table_skip_corrupt_index(node->index);
if (!node->index) {
break;
}
index = node->index;
if (row_upd_changes_ord_field_binary(node->index, node->update,
thr, NULL, NULL)) {
/* Build the older version of the index entry */
entry = row_build_index_entry(node->row, NULL,
index, heap);
ut_a(entry);
row_purge_remove_sec_if_poss(node, index, entry);
}
node->index = dict_table_get_next_index(node->index);
}
mem_heap_free(heap);
skip_secondaries:
/* Free possible externally stored fields */
for (i = 0; i < upd_get_n_fields(node->update); i++) {
const upd_field_t* ufield
= upd_get_nth_field(node->update, i);
if (dfield_is_ext(&ufield->new_val)) {
buf_block_t* block;
ulint internal_offset;
byte* data_field;
/* We use the fact that new_val points to
node->undo_rec and get thus the offset of
dfield data inside the undo record. Then we
can calculate from node->roll_ptr the file
address of the new_val data */
internal_offset
= ((const byte*)
dfield_get_data(&ufield->new_val))
- node->undo_rec;
ut_a(internal_offset < UNIV_PAGE_SIZE);
trx_undo_decode_roll_ptr(node->roll_ptr,
&is_insert, &rseg_id,
&page_no, &offset);
mtr_start(&mtr);
/* We have to acquire an X-latch to the clustered
index tree */
index = dict_table_get_first_index(node->table);
mtr_x_lock(dict_index_get_lock(index), &mtr);
/* NOTE: we must also acquire an X-latch to the
root page of the tree. We will need it when we
free pages from the tree. If the tree is of height 1,
the tree X-latch does NOT protect the root page,
because it is also a leaf page. Since we will have a
latch on an undo log page, we would break the
latching order if we would only later latch the
root page of such a tree! */
btr_root_get(index, &mtr);
/* We assume in purge of externally stored fields
that the space id of the undo log record is 0! */
block = buf_page_get(0, 0, page_no, RW_X_LATCH, &mtr);
buf_block_dbg_add_level(block, SYNC_TRX_UNDO_PAGE);
data_field = buf_block_get_frame(block)
+ offset + internal_offset;
ut_a(dfield_get_len(&ufield->new_val)
>= BTR_EXTERN_FIELD_REF_SIZE);
btr_free_externally_stored_field(
index,
data_field + dfield_get_len(&ufield->new_val)
- BTR_EXTERN_FIELD_REF_SIZE,
NULL, NULL, NULL, 0, RB_NONE, &mtr);
mtr_commit(&mtr);
}
}
}
/**********************************************************************//**
Reports in the undo log of an update or delete marking of a clustered index
record.
@return byte offset of the inserted undo log entry on the page if
succeed, 0 if fail */
static
ulint
trx_undo_page_report_modify(
/*========================*/
page_t* undo_page, /*!< in: undo log page */
trx_t* trx, /*!< in: transaction */
dict_index_t* index, /*!< in: clustered index where update or
delete marking is done */
const rec_t* rec, /*!< in: clustered index record which
has NOT yet been modified */
const ulint* offsets, /*!< in: rec_get_offsets(rec, index) */
const upd_t* update, /*!< in: update vector which tells the
columns to be updated; in the case of
a delete, this should be set to NULL */
ulint cmpl_info, /*!< in: compiler info on secondary
index updates */
mtr_t* mtr) /*!< in: mtr */
{
dict_table_t* table;
ulint first_free;
byte* ptr;
const byte* field;
ulint flen;
ulint col_no;
ulint type_cmpl;
byte* type_cmpl_ptr;
ulint i;
trx_id_t trx_id;
ibool ignore_prefix = FALSE;
byte ext_buf[REC_MAX_INDEX_COL_LEN
+ BTR_EXTERN_FIELD_REF_SIZE];
ut_a(dict_index_is_clust(index));
ut_ad(rec_offs_validate(rec, index, offsets));
ut_ad(mach_read_from_2(undo_page + TRX_UNDO_PAGE_HDR
+ TRX_UNDO_PAGE_TYPE) == TRX_UNDO_UPDATE);
table = index->table;
first_free = mach_read_from_2(undo_page + TRX_UNDO_PAGE_HDR
+ TRX_UNDO_PAGE_FREE);
ptr = undo_page + first_free;
ut_ad(first_free <= UNIV_PAGE_SIZE);
if (trx_undo_left(undo_page, ptr) < 50) {
/* NOTE: the value 50 must be big enough so that the general
fields written below fit on the undo log page */
return(0);
}
/* Reserve 2 bytes for the pointer to the next undo log record */
ptr += 2;
/* Store first some general parameters to the undo log */
if (!update) {
type_cmpl = TRX_UNDO_DEL_MARK_REC;
} else if (rec_get_deleted_flag(rec, dict_table_is_comp(table))) {
type_cmpl = TRX_UNDO_UPD_DEL_REC;
/* We are about to update a delete marked record.
We don't typically need the prefix in this case unless
the delete marking is done by the same transaction
(which we check below). */
ignore_prefix = TRUE;
} else {
type_cmpl = TRX_UNDO_UPD_EXIST_REC;
}
type_cmpl |= cmpl_info * TRX_UNDO_CMPL_INFO_MULT;
type_cmpl_ptr = ptr;
*ptr++ = (byte) type_cmpl;
ptr += mach_dulint_write_much_compressed(ptr, trx->undo_no);
ptr += mach_dulint_write_much_compressed(ptr, table->id);
/*----------------------------------------*/
/* Store the state of the info bits */
*ptr++ = (byte) rec_get_info_bits(rec, dict_table_is_comp(table));
/* Store the values of the system columns */
field = rec_get_nth_field(rec, offsets,
dict_index_get_sys_col_pos(
index, DATA_TRX_ID), &flen);
ut_ad(flen == DATA_TRX_ID_LEN);
trx_id = trx_read_trx_id(field);
/* If it is an update of a delete marked record, then we are
allowed to ignore blob prefixes if the delete marking was done
by some other trx as it must have committed by now for us to
allow an over-write. */
if (ignore_prefix) {
ignore_prefix = ut_dulint_cmp(trx_id, trx->id) != 0;
}
ptr += mach_dulint_write_compressed(ptr, trx_id);
field = rec_get_nth_field(rec, offsets,
dict_index_get_sys_col_pos(
index, DATA_ROLL_PTR), &flen);
ut_ad(flen == DATA_ROLL_PTR_LEN);
ptr += mach_dulint_write_compressed(ptr, trx_read_roll_ptr(field));
/*----------------------------------------*/
/* Store then the fields required to uniquely determine the
record which will be modified in the clustered index */
for (i = 0; i < dict_index_get_n_unique(index); i++) {
field = rec_get_nth_field(rec, offsets, i, &flen);
/* The ordering columns must not be stored externally. */
ut_ad(!rec_offs_nth_extern(offsets, i));
ut_ad(dict_index_get_nth_col(index, i)->ord_part);
if (trx_undo_left(undo_page, ptr) < 5) {
return(0);
}
ptr += mach_write_compressed(ptr, flen);
if (flen != UNIV_SQL_NULL) {
if (trx_undo_left(undo_page, ptr) < flen) {
return(0);
}
ut_memcpy(ptr, field, flen);
ptr += flen;
}
}
/*----------------------------------------*/
/* Save to the undo log the old values of the columns to be updated. */
if (update) {
if (trx_undo_left(undo_page, ptr) < 5) {
return(0);
}
ptr += mach_write_compressed(ptr, upd_get_n_fields(update));
for (i = 0; i < upd_get_n_fields(update); i++) {
ulint pos = upd_get_nth_field(update, i)->field_no;
/* Write field number to undo log */
if (trx_undo_left(undo_page, ptr) < 5) {
return(0);
}
ptr += mach_write_compressed(ptr, pos);
/* Save the old value of field */
field = rec_get_nth_field(rec, offsets, pos, &flen);
if (trx_undo_left(undo_page, ptr) < 15) {
return(0);
}
if (rec_offs_nth_extern(offsets, pos)) {
ptr = trx_undo_page_report_modify_ext(
ptr,
dict_index_get_nth_col(index, pos)
->ord_part
&& !ignore_prefix
&& flen < REC_MAX_INDEX_COL_LEN
? ext_buf : NULL,
dict_table_zip_size(table),
&field, &flen);
/* Notify purge that it eventually has to
free the old externally stored field */
trx->update_undo->del_marks = TRUE;
*type_cmpl_ptr |= TRX_UNDO_UPD_EXTERN;
} else {
ptr += mach_write_compressed(ptr, flen);
}
if (flen != UNIV_SQL_NULL) {
if (trx_undo_left(undo_page, ptr) < flen) {
return(0);
}
ut_memcpy(ptr, field, flen);
ptr += flen;
}
}
}
/*----------------------------------------*/
/* In the case of a delete marking, and also in the case of an update
where any ordering field of any index changes, store the values of all
columns which occur as ordering fields in any index. This info is used
in the purge of old versions where we use it to build and search the
delete marked index records, to look if we can remove them from the
index tree. Note that starting from 4.0.14 also externally stored
fields can be ordering in some index. Starting from 5.2, we no longer
store REC_MAX_INDEX_COL_LEN first bytes to the undo log record,
but we can construct the column prefix fields in the index by
fetching the first page of the BLOB that is pointed to by the
clustered index. This works also in crash recovery, because all pages
(including BLOBs) are recovered before anything is rolled back. */
if (!update || !(cmpl_info & UPD_NODE_NO_ORD_CHANGE)) {
byte* old_ptr = ptr;
trx->update_undo->del_marks = TRUE;
if (trx_undo_left(undo_page, ptr) < 5) {
return(0);
}
/* Reserve 2 bytes to write the number of bytes the stored
fields take in this undo record */
ptr += 2;
for (col_no = 0; col_no < dict_table_get_n_cols(table);
col_no++) {
const dict_col_t* col
= dict_table_get_nth_col(table, col_no);
if (col->ord_part) {
ulint pos;
/* Write field number to undo log */
if (trx_undo_left(undo_page, ptr) < 5 + 15) {
return(0);
}
pos = dict_index_get_nth_col_pos(index,
col_no);
ptr += mach_write_compressed(ptr, pos);
/* Save the old value of field */
field = rec_get_nth_field(rec, offsets, pos,
&flen);
if (rec_offs_nth_extern(offsets, pos)) {
ptr = trx_undo_page_report_modify_ext(
ptr,
flen < REC_MAX_INDEX_COL_LEN
&& !ignore_prefix
? ext_buf : NULL,
dict_table_zip_size(table),
&field, &flen);
} else {
ptr += mach_write_compressed(
ptr, flen);
}
if (flen != UNIV_SQL_NULL) {
if (trx_undo_left(undo_page, ptr)
< flen) {
return(0);
}
ut_memcpy(ptr, field, flen);
ptr += flen;
}
}
}
mach_write_to_2(old_ptr, ptr - old_ptr);
}
/*----------------------------------------*/
/* Write pointers to the previous and the next undo log records */
if (trx_undo_left(undo_page, ptr) < 2) {
return(0);
}
mach_write_to_2(ptr, first_free);
ptr += 2;
mach_write_to_2(undo_page + first_free, ptr - undo_page);
mach_write_to_2(undo_page + TRX_UNDO_PAGE_HDR + TRX_UNDO_PAGE_FREE,
ptr - undo_page);
/* Write to the REDO log about this change in the UNDO log */
trx_undof_page_add_undo_rec_log(undo_page, first_free,
ptr - undo_page, mtr);
return(first_free);
}
/*******************************************************************//**
Builds an update vector based on a remaining part of an undo log record.
@return remaining part of the record, NULL if an error detected, which
means that the record is corrupted */
UNIV_INTERN
byte*
trx_undo_update_rec_get_update(
/*===========================*/
byte* ptr, /*!< in: remaining part in update undo log
record, after reading the row reference
NOTE that this copy of the undo log record must
be preserved as long as the update vector is
used, as we do NOT copy the data in the
record! */
dict_index_t* index, /*!< in: clustered index */
ulint type, /*!< in: TRX_UNDO_UPD_EXIST_REC,
TRX_UNDO_UPD_DEL_REC, or
TRX_UNDO_DEL_MARK_REC; in the last case,
only trx id and roll ptr fields are added to
the update vector */
trx_id_t trx_id, /*!< in: transaction id from this undo record */
roll_ptr_t roll_ptr,/*!< in: roll pointer from this undo record */
ulint info_bits,/*!< in: info bits from this undo record */
trx_t* trx, /*!< in: transaction */
mem_heap_t* heap, /*!< in: memory heap from which the memory
needed is allocated */
upd_t** upd) /*!< out, own: update vector */
{
upd_field_t* upd_field;
upd_t* update;
ulint n_fields;
byte* buf;
ulint i;
ut_a(dict_index_is_clust(index));
if (type != TRX_UNDO_DEL_MARK_REC) {
ptr = trx_undo_update_rec_get_n_upd_fields(ptr, &n_fields);
} else {
n_fields = 0;
}
update = upd_create(n_fields + 2, heap);
update->info_bits = info_bits;
/* Store first trx id and roll ptr to update vector */
upd_field = upd_get_nth_field(update, n_fields);
buf = mem_heap_alloc(heap, DATA_TRX_ID_LEN);
trx_write_trx_id(buf, trx_id);
upd_field_set_field_no(upd_field,
dict_index_get_sys_col_pos(index, DATA_TRX_ID),
index, trx);
dfield_set_data(&(upd_field->new_val), buf, DATA_TRX_ID_LEN);
upd_field = upd_get_nth_field(update, n_fields + 1);
buf = mem_heap_alloc(heap, DATA_ROLL_PTR_LEN);
trx_write_roll_ptr(buf, roll_ptr);
upd_field_set_field_no(
upd_field, dict_index_get_sys_col_pos(index, DATA_ROLL_PTR),
index, trx);
dfield_set_data(&(upd_field->new_val), buf, DATA_ROLL_PTR_LEN);
/* Store then the updated ordinary columns to the update vector */
for (i = 0; i < n_fields; i++) {
byte* field;
ulint len;
ulint field_no;
ulint orig_len;
ptr = trx_undo_update_rec_get_field_no(ptr, &field_no);
if (field_no >= dict_index_get_n_fields(index)) {
fprintf(stderr,
"InnoDB: Error: trying to access"
" update undo rec field %lu in ",
(ulong) field_no);
dict_index_name_print(stderr, trx, index);
fprintf(stderr, "\n"
"InnoDB: but index has only %lu fields\n"
"InnoDB: Submit a detailed bug report"
" to http://bugs.mysql.com\n"
"InnoDB: Run also CHECK TABLE ",
(ulong) dict_index_get_n_fields(index));
ut_print_name(stderr, trx, TRUE, index->table_name);
fprintf(stderr, "\n"
"InnoDB: n_fields = %lu, i = %lu, ptr %p\n",
(ulong) n_fields, (ulong) i, ptr);
*upd = NULL;
return(NULL);
}
upd_field = upd_get_nth_field(update, i);
upd_field_set_field_no(upd_field, field_no, index, trx);
ptr = trx_undo_rec_get_col_val(ptr, &field, &len, &orig_len);
upd_field->orig_len = orig_len;
if (len == UNIV_SQL_NULL) {
dfield_set_null(&upd_field->new_val);
} else if (len < UNIV_EXTERN_STORAGE_FIELD) {
dfield_set_data(&upd_field->new_val, field, len);
} else {
len -= UNIV_EXTERN_STORAGE_FIELD;
dfield_set_data(&upd_field->new_val, field, len);
dfield_set_ext(&upd_field->new_val);
}
}
*upd = update;
return(ptr);
}
/***************************************************************
Purges an update of an existing record. Also purges an update of a delete
marked record if that record contained an externally stored field. */
static
void
row_purge_upd_exist_or_extern(
/*==========================*/
purge_node_t* node) /* in: row purge node */
{
mem_heap_t* heap;
dtuple_t* entry;
dict_index_t* index;
upd_field_t* ufield;
ibool is_insert;
ulint rseg_id;
ulint page_no;
ulint offset;
ulint internal_offset;
byte* data_field;
ulint data_field_len;
ulint i;
mtr_t mtr;
ut_ad(node);
if (node->rec_type == TRX_UNDO_UPD_DEL_REC) {
goto skip_secondaries;
}
heap = mem_heap_create(1024);
while (node->index != NULL) {
index = node->index;
if (row_upd_changes_ord_field_binary(NULL, node->index,
node->update)) {
/* Build the older version of the index entry */
entry = row_build_index_entry(node->row, index, heap);
row_purge_remove_sec_if_poss(node, index, entry);
}
node->index = dict_table_get_next_index(node->index);
}
mem_heap_free(heap);
skip_secondaries:
/* Free possible externally stored fields */
for (i = 0; i < upd_get_n_fields(node->update); i++) {
ufield = upd_get_nth_field(node->update, i);
if (ufield->extern_storage) {
/* We use the fact that new_val points to
node->undo_rec and get thus the offset of
dfield data inside the unod record. Then we
can calculate from node->roll_ptr the file
address of the new_val data */
internal_offset = ((byte*)ufield->new_val.data)
- node->undo_rec;
ut_a(internal_offset < UNIV_PAGE_SIZE);
trx_undo_decode_roll_ptr(node->roll_ptr,
&is_insert, &rseg_id,
&page_no, &offset);
mtr_start(&mtr);
/* We have to acquire an X-latch to the clustered
index tree */
index = dict_table_get_first_index(node->table);
mtr_x_lock(dict_index_get_lock(index), &mtr);
/* NOTE: we must also acquire an X-latch to the
root page of the tree. We will need it when we
free pages from the tree. If the tree is of height 1,
the tree X-latch does NOT protect the root page,
because it is also a leaf page. Since we will have a
latch on an undo log page, we would break the
latching order if we would only later latch the
root page of such a tree! */
btr_root_get(index, &mtr);
/* We assume in purge of externally stored fields
that the space id of the undo log record is 0! */
data_field = buf_page_get(0, page_no, RW_X_LATCH, &mtr)
+ offset + internal_offset;
#ifdef UNIV_SYNC_DEBUG
buf_page_dbg_add_level(buf_frame_align(data_field),
SYNC_TRX_UNDO_PAGE);
#endif /* UNIV_SYNC_DEBUG */
data_field_len = ufield->new_val.len;
btr_free_externally_stored_field(index, data_field,
data_field_len,
FALSE, &mtr);
mtr_commit(&mtr);
}
}
}
