mariadb/storage/innobase/row/row0row.c
Marko Mäkelä 41bb3537ba Bug#12704861 Corruption after a crash during BLOB update
The fix of Bug#12612184 broke crash recovery. When a record that
contains off-page columns (BLOBs) is updated, we must first write redo
log about the BLOB page writes, and only after that write the redo log
about the B-tree changes. The buggy fix would log the B-tree changes
first, meaning that after recovery, we could end up having a record
that contains a null BLOB pointer.

Because we will be redo logging the writes off the off-page columns
before the B-tree changes, we must make sure that the pages chosen for
the off-page columns are free both before and after the B-tree
changes. In this way, the worst thing that can happen in crash
recovery is that the BLOBs are written to free pages, but the B-tree
changes are not applied. The BLOB pages would correctly remain free in
this case. To achieve this, we must allocate the BLOB pages in the
mini-transaction of the B-tree operation. A further quirk is that BLOB
pages are allocated from the same file segment as leaf pages. Because
of this, we must temporarily "hide" any leaf pages that were freed
during the B-tree operation by "fake allocating" them prior to writing
the BLOBs, and freeing them again before the mtr_commit() of the
B-tree operation, in btr_mark_freed_leaves().

btr_cur_mtr_commit_and_start(): Remove this faulty function that was
introduced in the Bug#12612184 fix. The problem that this function was
trying to address was that when we did mtr_commit() the BLOB writes
before the mtr_commit() of the update, the new BLOB pages could have
overwritten clustered index B-tree leaf pages that were freed during
the update. If recovery applied the redo log of the BLOB writes but
did not see the log of the record update, the index tree would be
corrupted. The correct solution is to make the freed clustered index
pages unavailable to the BLOB allocation. This function is also a
likely culprit of InnoDB hangs that were observed when testing the
Bug#12612184 fix.

btr_mark_freed_leaves(): Mark all freed clustered index leaf pages of
a mini-transaction allocated (nonfree=TRUE) before storing the BLOBs,
or freed (nonfree=FALSE) before committing the mini-transaction.

btr_freed_leaves_validate(): A debug function for checking that all
clustered index leaf pages that have been marked free in the
mini-transaction are consistent (have not been zeroed out).

btr_page_alloc_low(): Refactored from btr_page_alloc(). Return the
number of the allocated page, or FIL_NULL if out of space. Add the
parameter "mtr_t* init_mtr" for specifying the mini-transaction where
the page should be initialized, or if this is a "fake allocation"
(init_mtr=NULL) by btr_mark_freed_leaves(nonfree=TRUE).

btr_page_alloc(): Add the parameter init_mtr, allowing the page to be
initialized and X-latched in a different mini-transaction than the one
that is used for the allocation. Invoke btr_page_alloc_low(). If a
clustered index leaf page was previously freed in mtr, remove it from
the memo of previously freed pages.

btr_page_free(): Assert that the page is a B-tree page and it has been
X-latched by the mini-transaction. If the freed page was a leaf page
of a clustered index, link it by a MTR_MEMO_FREE_CLUST_LEAF marker to
the mini-transaction.

btr_store_big_rec_extern_fields_func(): Add the parameter alloc_mtr,
which is NULL (old behaviour in inserts) and the same as local_mtr in
updates. If alloc_mtr!=NULL, the BLOB pages will be allocated from it
instead of the mini-transaction that is used for writing the BLOBs.

fsp_alloc_from_free_frag(): Refactored from
fsp_alloc_free_page(). Allocate the specified page from a partially
free extent.

fseg_alloc_free_page_low(), fseg_alloc_free_page_general(): Add the
parameter "mtr_t* init_mtr" for specifying the mini-transaction where
the page should be initialized, or NULL if this is a "fake allocation"
that prevents the reuse of a previously freed B-tree page for BLOB
storage. If init_mtr==NULL, try harder to reallocate the specified page
and assert that it succeeded.

fsp_alloc_free_page(): Add the parameter "mtr_t* init_mtr" for
specifying the mini-transaction where the page should be initialized.
Do not allow init_mtr == NULL, because this function is never to be
used for "fake allocations".

mtr_t: Add the operation MTR_MEMO_FREE_CLUST_LEAF and the flag
mtr->freed_clust_leaf for quickly determining if any
MTR_MEMO_FREE_CLUST_LEAF operations have been posted.

row_ins_index_entry_low(): When columns are being made off-page in
insert-by-update, invoke btr_mark_freed_leaves(nonfree=TRUE) and pass
the mini-transaction as the alloc_mtr to
btr_store_big_rec_extern_fields(). Finally, invoke
btr_mark_freed_leaves(nonfree=FALSE) to avoid leaking pages.

row_build(): Correct a comment, and add a debug assertion that a
record that contains NULL BLOB pointers must be a fresh insert.

row_upd_clust_rec(): When columns are being moved off-page, invoke
btr_mark_freed_leaves(nonfree=TRUE) and pass the mini-transaction as
the alloc_mtr to btr_store_big_rec_extern_fields(). Finally, invoke
btr_mark_freed_leaves(nonfree=FALSE) to avoid leaking pages.

buf_reset_check_index_page_at_flush(): Remove. The function
fsp_init_file_page_low() already sets
bpage->check_index_page_at_flush=FALSE.

There is a known issue in tablespace extension. If the request to
allocate a BLOB page leads to the tablespace being extended, crash
recovery could see BLOB writes to pages that are off the tablespace
file bounds. This should trigger an assertion failure in fil_io() at
crash recovery. The safe thing would be to write redo log about the
tablespace extension to the mini-transaction of the BLOB write, not to
the mini-transaction of the record update. However, there is no redo
log record for file extension in the current redo log format.

rb:693 approved by Sunny Bains
2011-08-29 11:16:42 +03:00

755 lines
19 KiB
C

/******************************************************
General row routines
(c) 1996 Innobase Oy
Created 4/20/1996 Heikki Tuuri
*******************************************************/
#include "row0row.h"
#ifdef UNIV_NONINL
#include "row0row.ic"
#endif
#include "dict0dict.h"
#include "btr0btr.h"
#include "mach0data.h"
#include "trx0rseg.h"
#include "trx0trx.h"
#include "trx0roll.h"
#include "trx0undo.h"
#include "trx0purge.h"
#include "trx0rec.h"
#include "que0que.h"
#include "row0row.h"
#include "row0upd.h"
#include "rem0cmp.h"
#include "read0read.h"
/*************************************************************************
Reads the trx id or roll ptr field from a clustered index record: this function
is slower than the specialized inline functions. */
dulint
row_get_rec_sys_field(
/*==================*/
/* out: value of the field */
ulint type, /* in: DATA_TRX_ID or DATA_ROLL_PTR */
rec_t* rec, /* in: record */
dict_index_t* index, /* in: clustered index */
const ulint* offsets)/* in: rec_get_offsets(rec, index) */
{
ulint pos;
byte* field;
ulint len;
ut_ad(index->type & DICT_CLUSTERED);
pos = dict_index_get_sys_col_pos(index, type);
field = rec_get_nth_field(rec, offsets, pos, &len);
if (type == DATA_TRX_ID) {
return(trx_read_trx_id(field));
} else {
ut_ad(type == DATA_ROLL_PTR);
return(trx_read_roll_ptr(field));
}
}
/*************************************************************************
Sets the trx id or roll ptr field in a clustered index record: this function
is slower than the specialized inline functions. */
void
row_set_rec_sys_field(
/*==================*/
/* out: value of the field */
ulint type, /* in: DATA_TRX_ID or DATA_ROLL_PTR */
rec_t* rec, /* in: record */
dict_index_t* index, /* in: clustered index */
const ulint* offsets,/* in: rec_get_offsets(rec, index) */
dulint val) /* in: value to set */
{
ulint pos;
byte* field;
ulint len;
ut_ad(index->type & DICT_CLUSTERED);
ut_ad(rec_offs_validate(rec, index, offsets));
pos = dict_index_get_sys_col_pos(index, type);
field = rec_get_nth_field(rec, offsets, pos, &len);
if (type == DATA_TRX_ID) {
trx_write_trx_id(field, val);
} else {
ut_ad(type == DATA_ROLL_PTR);
trx_write_roll_ptr(field, val);
}
}
/*********************************************************************
When an insert to a table is performed, this function builds the entry which
has to be inserted to an index on the table. */
dtuple_t*
row_build_index_entry(
/*==================*/
/* out: index entry which should be inserted */
dtuple_t* row, /* in: row which should be inserted to the
table */
dict_index_t* index, /* in: index on the table */
mem_heap_t* heap) /* in: memory heap from which the memory for
the index entry is allocated */
{
dtuple_t* entry;
ulint entry_len;
dict_field_t* ind_field;
dfield_t* dfield;
dfield_t* dfield2;
ulint i;
ulint storage_len;
ut_ad(row && index && heap);
ut_ad(dtuple_check_typed(row));
entry_len = dict_index_get_n_fields(index);
entry = dtuple_create(heap, entry_len);
if (index->type & DICT_UNIVERSAL) {
dtuple_set_n_fields_cmp(entry, entry_len);
} else {
dtuple_set_n_fields_cmp(
entry, dict_index_get_n_unique_in_tree(index));
}
for (i = 0; i < entry_len; i++) {
const dict_col_t* col;
ind_field = dict_index_get_nth_field(index, i);
col = ind_field->col;
dfield = dtuple_get_nth_field(entry, i);
dfield2 = dtuple_get_nth_field(row, dict_col_get_no(col));
dfield_copy(dfield, dfield2);
/* If a column prefix index, take only the prefix */
if (ind_field->prefix_len > 0
&& dfield_get_len(dfield2) != UNIV_SQL_NULL) {
storage_len = dtype_get_at_most_n_mbchars(
col->prtype, col->mbminlen, col->mbmaxlen,
ind_field->prefix_len,
dfield_get_len(dfield2), dfield2->data);
dfield_set_len(dfield, storage_len);
}
}
ut_ad(dtuple_check_typed(entry));
return(entry);
}
/***********************************************************************
An inverse function to dict_row_build_index_entry. Builds a row from a
record in a clustered index. */
dtuple_t*
row_build(
/*======*/
/* out, own: row built; see the NOTE below! */
ulint type, /* in: ROW_COPY_POINTERS or ROW_COPY_DATA;
the latter copies also the data fields to
heap while the first only places pointers to
data fields on the index page, and thus is
more efficient */
dict_index_t* index, /* in: clustered index */
rec_t* rec, /* in: record in the clustered index;
NOTE: in the case ROW_COPY_POINTERS
the data fields in the row will point
directly into this record, therefore,
the buffer page of this record must be
at least s-latched and the latch held
as long as the row dtuple is used! */
const ulint* offsets,/* in: rec_get_offsets(rec, index)
or NULL, in which case this function
will invoke rec_get_offsets() */
mem_heap_t* heap) /* in: memory heap from which the memory
needed is allocated */
{
dtuple_t* row;
dict_table_t* table;
dict_field_t* ind_field;
dfield_t* dfield;
ulint n_fields;
byte* field;
ulint len;
ulint row_len;
byte* buf;
ulint i;
mem_heap_t* tmp_heap = NULL;
ulint offsets_[REC_OFFS_NORMAL_SIZE];
*offsets_ = (sizeof offsets_) / sizeof *offsets_;
ut_ad(index && rec && heap);
ut_ad(index->type & DICT_CLUSTERED);
ut_ad(!mutex_own(&kernel_mutex));
if (!offsets) {
offsets = rec_get_offsets(rec, index, offsets_,
ULINT_UNDEFINED, &tmp_heap);
} else {
ut_ad(rec_offs_validate(rec, index, offsets));
}
#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
if (rec_offs_any_null_extern(rec, offsets)) {
/* This condition can occur during crash recovery
before trx_rollback_or_clean_all_without_sess() has
completed execution.
This condition is possible if the server crashed
during an insert or update before
btr_store_big_rec_extern_fields() did mtr_commit() all
BLOB pointers to the clustered index record.
If the record contains a null BLOB pointer, look up the
transaction that holds the implicit lock on this record, and
assert that it is active. (In this version of InnoDB, we
cannot assert that it was recovered, because there is no
trx->is_recovered field.) */
ut_a(trx_assert_active(
row_get_rec_trx_id(rec, index, offsets)));
ut_a(trx_undo_roll_ptr_is_insert(
row_get_rec_roll_ptr(rec, index, offsets)));
}
#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */
if (type != ROW_COPY_POINTERS) {
/* Take a copy of rec to heap */
buf = mem_heap_alloc(heap, rec_offs_size(offsets));
rec = rec_copy(buf, rec, offsets);
/* Avoid a debug assertion in rec_offs_validate(). */
rec_offs_make_valid(rec, index, (ulint*) offsets);
}
table = index->table;
row_len = dict_table_get_n_cols(table);
row = dtuple_create(heap, row_len);
dtuple_set_info_bits(row, rec_get_info_bits(
rec, dict_table_is_comp(table)));
n_fields = rec_offs_n_fields(offsets);
dict_table_copy_types(row, table);
for (i = 0; i < n_fields; i++) {
ind_field = dict_index_get_nth_field(index, i);
if (ind_field->prefix_len == 0) {
const dict_col_t* col
= dict_field_get_col(ind_field);
dfield = dtuple_get_nth_field(row,
dict_col_get_no(col));
field = rec_get_nth_field(rec, offsets, i, &len);
dfield_set_data(dfield, field, len);
}
}
ut_ad(dtuple_check_typed(row));
if (tmp_heap) {
mem_heap_free(tmp_heap);
}
return(row);
}
/***********************************************************************
Converts an index record to a typed data tuple. NOTE that externally
stored (often big) fields are NOT copied to heap. */
dtuple_t*
row_rec_to_index_entry(
/*===================*/
/* out, own: index entry built; see the
NOTE below! */
ulint type, /* in: ROW_COPY_DATA, or ROW_COPY_POINTERS:
the former copies also the data fields to
heap as the latter only places pointers to
data fields on the index page */
dict_index_t* index, /* in: index */
rec_t* rec, /* in: record in the index;
NOTE: in the case ROW_COPY_POINTERS
the data fields in the row will point
directly into this record, therefore,
the buffer page of this record must be
at least s-latched and the latch held
as long as the dtuple is used! */
mem_heap_t* heap) /* in: memory heap from which the memory
needed is allocated */
{
dtuple_t* entry;
dfield_t* dfield;
ulint i;
byte* field;
ulint len;
ulint rec_len;
byte* buf;
mem_heap_t* tmp_heap = NULL;
ulint offsets_[REC_OFFS_NORMAL_SIZE];
ulint* offsets = offsets_;
*offsets_ = (sizeof offsets_) / sizeof *offsets_;
ut_ad(rec && heap && index);
offsets = rec_get_offsets(rec, index, offsets,
ULINT_UNDEFINED, &tmp_heap);
if (type == ROW_COPY_DATA) {
/* Take a copy of rec to heap */
buf = mem_heap_alloc(heap, rec_offs_size(offsets));
rec = rec_copy(buf, rec, offsets);
/* Avoid a debug assertion in rec_offs_validate(). */
rec_offs_make_valid(rec, index, offsets);
#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
} else {
ut_a(!rec_offs_any_null_extern(rec, offsets));
#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */
}
rec_len = rec_offs_n_fields(offsets);
entry = dtuple_create(heap, rec_len);
dtuple_set_n_fields_cmp(entry,
dict_index_get_n_unique_in_tree(index));
ut_ad(rec_len == dict_index_get_n_fields(index));
dict_index_copy_types(entry, index, rec_len);
dtuple_set_info_bits(entry,
rec_get_info_bits(rec, rec_offs_comp(offsets)));
for (i = 0; i < rec_len; i++) {
dfield = dtuple_get_nth_field(entry, i);
field = rec_get_nth_field(rec, offsets, i, &len);
dfield_set_data(dfield, field, len);
}
ut_ad(dtuple_check_typed(entry));
if (tmp_heap) {
mem_heap_free(tmp_heap);
}
return(entry);
}
/***********************************************************************
Builds from a secondary index record a row reference with which we can
search the clustered index record. */
dtuple_t*
row_build_row_ref(
/*==============*/
/* out, own: row reference built; see the
NOTE below! */
ulint type, /* in: ROW_COPY_DATA, or ROW_COPY_POINTERS:
the former copies also the data fields to
heap, whereas the latter only places pointers
to data fields on the index page */
dict_index_t* index, /* in: index */
rec_t* rec, /* in: record in the index;
NOTE: in the case ROW_COPY_POINTERS
the data fields in the row will point
directly into this record, therefore,
the buffer page of this record must be
at least s-latched and the latch held
as long as the row reference is used! */
mem_heap_t* heap) /* in: memory heap from which the memory
needed is allocated */
{
dict_table_t* table;
dict_index_t* clust_index;
dfield_t* dfield;
dtuple_t* ref;
byte* field;
ulint len;
ulint ref_len;
ulint pos;
byte* buf;
ulint clust_col_prefix_len;
ulint i;
mem_heap_t* tmp_heap = NULL;
ulint offsets_[REC_OFFS_NORMAL_SIZE];
ulint* offsets = offsets_;
*offsets_ = (sizeof offsets_) / sizeof *offsets_;
ut_ad(index && rec && heap);
offsets = rec_get_offsets(rec, index, offsets,
ULINT_UNDEFINED, &tmp_heap);
if (type == ROW_COPY_DATA) {
/* Take a copy of rec to heap */
buf = mem_heap_alloc(heap, rec_offs_size(offsets));
rec = rec_copy(buf, rec, offsets);
/* Avoid a debug assertion in rec_offs_validate(). */
rec_offs_make_valid(rec, index, offsets);
}
table = index->table;
clust_index = dict_table_get_first_index(table);
ref_len = dict_index_get_n_unique(clust_index);
ref = dtuple_create(heap, ref_len);
dict_index_copy_types(ref, clust_index, ref_len);
for (i = 0; i < ref_len; i++) {
dfield = dtuple_get_nth_field(ref, i);
pos = dict_index_get_nth_field_pos(index, clust_index, i);
ut_a(pos != ULINT_UNDEFINED);
field = rec_get_nth_field(rec, offsets, pos, &len);
dfield_set_data(dfield, field, len);
/* If the primary key contains a column prefix, then the
secondary index may contain a longer prefix of the same
column, or the full column, and we must adjust the length
accordingly. */
clust_col_prefix_len = dict_index_get_nth_field(
clust_index, i)->prefix_len;
if (clust_col_prefix_len > 0) {
if (len != UNIV_SQL_NULL) {
const dtype_t* dtype
= dfield_get_type(dfield);
dfield_set_len(dfield,
dtype_get_at_most_n_mbchars(
dtype->prtype,
dtype->mbminlen,
dtype->mbmaxlen,
clust_col_prefix_len,
len, (char*) field));
}
}
}
ut_ad(dtuple_check_typed(ref));
if (tmp_heap) {
mem_heap_free(tmp_heap);
}
return(ref);
}
/***********************************************************************
Builds from a secondary index record a row reference with which we can
search the clustered index record. */
void
row_build_row_ref_in_tuple(
/*=======================*/
dtuple_t* ref, /* in/out: row reference built; see the
NOTE below! */
dict_index_t* index, /* in: index */
rec_t* rec, /* in: record in the index;
NOTE: the data fields in ref will point
directly into this record, therefore,
the buffer page of this record must be
at least s-latched and the latch held
as long as the row reference is used! */
trx_t* trx) /* in: transaction */
{
dict_index_t* clust_index;
dfield_t* dfield;
byte* field;
ulint len;
ulint ref_len;
ulint pos;
ulint clust_col_prefix_len;
ulint i;
mem_heap_t* heap = NULL;
ulint offsets_[REC_OFFS_NORMAL_SIZE];
ulint* offsets = offsets_;
*offsets_ = (sizeof offsets_) / sizeof *offsets_;
ut_a(ref);
ut_a(index);
ut_a(rec);
if (UNIV_UNLIKELY(!index->table)) {
fputs("InnoDB: table ", stderr);
notfound:
ut_print_name(stderr, trx, TRUE, index->table_name);
fputs(" for index ", stderr);
ut_print_name(stderr, trx, FALSE, index->name);
fputs(" not found\n", stderr);
ut_error;
}
clust_index = dict_table_get_first_index(index->table);
if (!clust_index) {
fputs("InnoDB: clust index for table ", stderr);
goto notfound;
}
offsets = rec_get_offsets(rec, index, offsets, ULINT_UNDEFINED, &heap);
ref_len = dict_index_get_n_unique(clust_index);
ut_ad(ref_len == dtuple_get_n_fields(ref));
dict_index_copy_types(ref, clust_index, ref_len);
for (i = 0; i < ref_len; i++) {
dfield = dtuple_get_nth_field(ref, i);
pos = dict_index_get_nth_field_pos(index, clust_index, i);
ut_a(pos != ULINT_UNDEFINED);
field = rec_get_nth_field(rec, offsets, pos, &len);
dfield_set_data(dfield, field, len);
/* If the primary key contains a column prefix, then the
secondary index may contain a longer prefix of the same
column, or the full column, and we must adjust the length
accordingly. */
clust_col_prefix_len = dict_index_get_nth_field(
clust_index, i)->prefix_len;
if (clust_col_prefix_len > 0) {
if (len != UNIV_SQL_NULL) {
const dtype_t* dtype
= dfield_get_type(dfield);
dfield_set_len(dfield,
dtype_get_at_most_n_mbchars(
dtype->prtype,
dtype->mbminlen,
dtype->mbmaxlen,
clust_col_prefix_len,
len, (char*) field));
}
}
}
ut_ad(dtuple_check_typed(ref));
if (UNIV_LIKELY_NULL(heap)) {
mem_heap_free(heap);
}
}
/***********************************************************************
From a row build a row reference with which we can search the clustered
index record. */
void
row_build_row_ref_from_row(
/*=======================*/
dtuple_t* ref, /* in/out: row reference built; see the
NOTE below! ref must have the right number
of fields! */
dict_table_t* table, /* in: table */
dtuple_t* row) /* in: row
NOTE: the data fields in ref will point
directly into data of this row */
{
dict_index_t* clust_index;
ulint ref_len;
ulint i;
ut_ad(ref && table && row);
clust_index = dict_table_get_first_index(table);
ref_len = dict_index_get_n_unique(clust_index);
ut_ad(ref_len == dtuple_get_n_fields(ref));
for (i = 0; i < ref_len; i++) {
const dict_col_t* col;
dict_field_t* field;
dfield_t* dfield;
dfield_t* dfield2;
dfield = dtuple_get_nth_field(ref, i);
field = dict_index_get_nth_field(clust_index, i);
col = dict_field_get_col(field);
dfield2 = dtuple_get_nth_field(row, dict_col_get_no(col));
dfield_copy(dfield, dfield2);
if (field->prefix_len > 0
&& dfield->len != UNIV_SQL_NULL) {
dfield->len = dtype_get_at_most_n_mbchars(
col->prtype, col->mbminlen, col->mbmaxlen,
field->prefix_len, dfield->len, dfield->data);
}
}
ut_ad(dtuple_check_typed(ref));
}
/*******************************************************************
Searches the clustered index record for a row, if we have the row reference. */
ibool
row_search_on_row_ref(
/*==================*/
/* out: TRUE if found */
btr_pcur_t* pcur, /* in/out: persistent cursor, which must
be closed by the caller */
ulint mode, /* in: BTR_MODIFY_LEAF, ... */
dict_table_t* table, /* in: table */
dtuple_t* ref, /* in: row reference */
mtr_t* mtr) /* in: mtr */
{
ulint low_match;
rec_t* rec;
dict_index_t* index;
ut_ad(dtuple_check_typed(ref));
index = dict_table_get_first_index(table);
ut_a(dtuple_get_n_fields(ref) == dict_index_get_n_unique(index));
btr_pcur_open(index, ref, PAGE_CUR_LE, mode, pcur, mtr);
low_match = btr_pcur_get_low_match(pcur);
rec = btr_pcur_get_rec(pcur);
if (page_rec_is_infimum(rec)) {
return(FALSE);
}
if (low_match != dtuple_get_n_fields(ref)) {
return(FALSE);
}
return(TRUE);
}
/*************************************************************************
Fetches the clustered index record for a secondary index record. The latches
on the secondary index record are preserved. */
rec_t*
row_get_clust_rec(
/*==============*/
/* out: record or NULL, if no record found */
ulint mode, /* in: BTR_MODIFY_LEAF, ... */
rec_t* rec, /* in: record in a secondary index */
dict_index_t* index, /* in: secondary index */
dict_index_t** clust_index,/* out: clustered index */
mtr_t* mtr) /* in: mtr */
{
mem_heap_t* heap;
dtuple_t* ref;
dict_table_t* table;
btr_pcur_t pcur;
ibool found;
rec_t* clust_rec;
ut_ad((index->type & DICT_CLUSTERED) == 0);
table = index->table;
heap = mem_heap_create(256);
ref = row_build_row_ref(ROW_COPY_POINTERS, index, rec, heap);
found = row_search_on_row_ref(&pcur, mode, table, ref, mtr);
clust_rec = found ? btr_pcur_get_rec(&pcur) : NULL;
mem_heap_free(heap);
btr_pcur_close(&pcur);
*clust_index = dict_table_get_first_index(table);
return(clust_rec);
}
/*******************************************************************
Searches an index record. */
ibool
row_search_index_entry(
/*===================*/
/* out: TRUE if found */
dict_index_t* index, /* in: index */
dtuple_t* entry, /* in: index entry */
ulint mode, /* in: BTR_MODIFY_LEAF, ... */
btr_pcur_t* pcur, /* in/out: persistent cursor, which must
be closed by the caller */
mtr_t* mtr) /* in: mtr */
{
ulint n_fields;
ulint low_match;
rec_t* rec;
ut_ad(dtuple_check_typed(entry));
btr_pcur_open(index, entry, PAGE_CUR_LE, mode, pcur, mtr);
low_match = btr_pcur_get_low_match(pcur);
rec = btr_pcur_get_rec(pcur);
n_fields = dtuple_get_n_fields(entry);
if (page_rec_is_infimum(rec)) {
return(FALSE);
}
if (low_match != n_fields) {
/* Not found */
return(FALSE);
}
return(TRUE);
}