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mariadb/storage/innobase/rem/rem0cmp.cc
Marko Mäkelä 5bada1246d Merge 10.5 into 10.6
2023-04-11 16:15:19 +03:00

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/*****************************************************************************
Copyright (c) 1994, 2019, Oracle and/or its affiliates. All Rights Reserved.
Copyright (c) 2020, 2022, MariaDB Corporation.
This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA
*****************************************************************************/
/*******************************************************************//**
@file rem/rem0cmp.cc
Comparison services for records
Created 7/1/1994 Heikki Tuuri
************************************************************************/
#include "rem0cmp.h"
#include "rem0rec.h"
#include "page0page.h"
#include "dict0mem.h"
#include "handler0alter.h"
/* ALPHABETICAL ORDER
==================
The records are put into alphabetical order in the following
way: let F be the first field where two records disagree.
If there is a character in some position n where the
records disagree, the order is determined by comparison of
the characters at position n, possibly after
collating transformation. If there is no such character,
but the corresponding fields have different lengths, then
if the data type of the fields is paddable,
shorter field is padded with a padding character. If the
data type is not paddable, longer field is considered greater.
Finally, the SQL null is bigger than any other value.
At the present, the comparison functions return 0 in the case,
where two records disagree only in the way that one
has more fields than the other. */
#ifndef DBUG_OFF
/** @return whether a data type is compatible with strnncoll() functions */
static bool is_strnncoll_compatible(ulint type)
{
switch (type) {
case MYSQL_TYPE_BIT:
case MYSQL_TYPE_STRING:
case MYSQL_TYPE_VAR_STRING:
case MYSQL_TYPE_TINY_BLOB:
case MYSQL_TYPE_MEDIUM_BLOB:
case MYSQL_TYPE_BLOB:
case MYSQL_TYPE_LONG_BLOB:
case MYSQL_TYPE_VARCHAR:
return true;
default:
return false;
}
}
#endif /* DBUG_OFF */
/*************************************************************//**
Returns TRUE if two columns are equal for comparison purposes.
@return TRUE if the columns are considered equal in comparisons */
ibool
cmp_cols_are_equal(
/*===============*/
const dict_col_t* col1, /*!< in: column 1 */
const dict_col_t* col2, /*!< in: column 2 */
ibool check_charsets)
/*!< in: whether to check charsets */
{
if (dtype_is_non_binary_string_type(col1->mtype, col1->prtype)
&& dtype_is_non_binary_string_type(col2->mtype, col2->prtype)) {
/* Both are non-binary string types: they can be compared if
and only if the charset-collation is the same */
if (check_charsets) {
return(dtype_get_charset_coll(col1->prtype)
== dtype_get_charset_coll(col2->prtype));
} else {
return(TRUE);
}
}
if (dtype_is_binary_string_type(col1->mtype, col1->prtype)
&& dtype_is_binary_string_type(col2->mtype, col2->prtype)) {
/* Both are binary string types: they can be compared */
return(TRUE);
}
if (col1->mtype != col2->mtype) {
return(FALSE);
}
if (col1->mtype == DATA_INT
&& (col1->prtype & DATA_UNSIGNED)
!= (col2->prtype & DATA_UNSIGNED)) {
/* The storage format of an unsigned integer is different
from a signed integer: in a signed integer we OR
0x8000... to the value of positive integers. */
return(FALSE);
}
return(col1->mtype != DATA_INT || col1->len == col2->len);
}
/** Compare two DATA_DECIMAL (MYSQL_TYPE_DECIMAL) fields.
TODO: Remove this function. Everything should use MYSQL_TYPE_NEWDECIMAL.
@param[in] a data field
@param[in] a_length length of a, in bytes (not UNIV_SQL_NULL)
@param[in] b data field
@param[in] b_length length of b, in bytes (not UNIV_SQL_NULL)
@return positive, 0, negative, if a is greater, equal, less than b,
respectively */
static ATTRIBUTE_COLD
int
cmp_decimal(const byte* a, ulint a_length, const byte* b, ulint b_length)
{
int swap_flag;
/* Remove preceding spaces */
for (; a_length && *a == ' '; a++, a_length--) { }
for (; b_length && *b == ' '; b++, b_length--) { }
if (*a == '-') {
swap_flag = -1;
if (*b != '-') {
return(swap_flag);
}
a++; b++;
a_length--;
b_length--;
} else {
swap_flag = 1;
if (*b == '-') {
return(swap_flag);
}
}
while (a_length > 0 && (*a == '+' || *a == '0')) {
a++; a_length--;
}
while (b_length > 0 && (*b == '+' || *b == '0')) {
b++; b_length--;
}
if (a_length != b_length) {
if (a_length < b_length) {
return(-swap_flag);
}
return(swap_flag);
}
while (a_length > 0 && *a == *b) {
a++; b++; a_length--;
}
if (a_length == 0) {
return(0);
}
if (*a <= *b) {
swap_flag = -swap_flag;
}
return(swap_flag);
}
/** Compare two data fields.
@param mtype main type
@param prtype precise type
@param data1 data field
@param len1 length of data1 in bytes, or UNIV_SQL_NULL
@param data2 data field
@param len2 length of data2 in bytes, or UNIV_SQL_NULL
@return the comparison result of data1 and data2
@retval 0 if data1 is equal to data2
@retval negative if data1 is less than data2
@retval positive if data1 is greater than data2 */
static int cmp_data(ulint mtype, ulint prtype, const byte *data1, ulint len1,
const byte *data2, ulint len2)
{
ut_ad(len1 != UNIV_SQL_DEFAULT);
ut_ad(len2 != UNIV_SQL_DEFAULT);
if (len1 == UNIV_SQL_NULL || len2 == UNIV_SQL_NULL)
{
if (len1 == len2)
return 0;
/* We define the SQL null to be the smallest possible value of a field. */
return len1 == UNIV_SQL_NULL ? -1 : 1;
}
switch (mtype) {
default:
ib::fatal() << "Unknown data type number " << mtype;
case DATA_DECIMAL:
return cmp_decimal(data1, len1, data2, len2);
case DATA_DOUBLE:
{
const double af= mach_double_read(data1), bf= mach_double_read(data2);
return af > bf ? 1 : bf > af ? -1 : 0;
}
case DATA_FLOAT:
{
const float af= mach_float_read(data1), bf= mach_float_read(data2);
return af > bf ? 1 : bf > af ? -1 : 0;
}
case DATA_FIXBINARY:
case DATA_BINARY:
if (dtype_get_charset_coll(prtype) != DATA_MYSQL_BINARY_CHARSET_COLL)
{
if (ulint len= std::min(len1, len2))
{
if (int cmp= memcmp(data1, data2, len))
return cmp;
data1+= len;
data2+= len;
len1-= len;
len2-= len;
}
int cmp= 0;
if (len1)
{
const byte *end= &data1[len1];
do
cmp= static_cast<int>(*data1++ - byte{0x20});
while (cmp == 0 && data1 < end);
}
else if (len2)
{
const byte *end= &data2[len2];
do
cmp= static_cast<int>(byte{0x20} - *data2++);
while (cmp == 0 && data2 < end);
}
return cmp;
}
/* fall through */
case DATA_INT:
case DATA_SYS_CHILD:
case DATA_SYS:
break;
case DATA_GEOMETRY:
ut_ad(prtype & DATA_BINARY_TYPE);
if (prtype & DATA_GIS_MBR)
{
ut_ad(len1 == DATA_MBR_LEN);
ut_ad(len2 == DATA_MBR_LEN);
return cmp_geometry_field(data1, data2);
}
break;
case DATA_BLOB:
if (prtype & DATA_BINARY_TYPE)
break;
/* fall through */
case DATA_VARMYSQL:
DBUG_ASSERT(is_strnncoll_compatible(prtype & DATA_MYSQL_TYPE_MASK));
if (CHARSET_INFO *cs= all_charsets[dtype_get_charset_coll(prtype)])
return cs->coll->strnncollsp(cs, data1, len1, data2, len2);
no_collation:
ib::fatal() << "Unable to find charset-collation for " << prtype;
case DATA_MYSQL:
DBUG_ASSERT(is_strnncoll_compatible(prtype & DATA_MYSQL_TYPE_MASK));
if (CHARSET_INFO *cs= all_charsets[dtype_get_charset_coll(prtype)])
return cs->coll->strnncollsp_nchars(cs, data1, len1, data2, len2,
std::max(len1, len2),
MY_STRNNCOLLSP_NCHARS_EMULATE_TRIMMED_TRAILING_SPACES);
goto no_collation;
case DATA_VARCHAR:
case DATA_CHAR:
/* latin1_swedish_ci is treated as a special case in InnoDB.
Because it is a fixed-length encoding (mbminlen=mbmaxlen=1),
non-NULL CHAR(n) values will always occupy n bytes and we
can invoke strnncollsp() instead of strnncollsp_nchars(). */
return my_charset_latin1.strnncollsp(data1, len1, data2, len2);
}
if (ulint len= std::min(len1, len2))
if (int cmp= memcmp(data1, data2, len))
return cmp;
return len1 > len2 ? 1 : len2 > len1 ? -1 : 0;
}
/** Compare two data fields.
@param[in] mtype main type
@param[in] prtype precise type
@param[in] data1 data field
@param[in] len1 length of data1 in bytes, or UNIV_SQL_NULL
@param[in] data2 data field
@param[in] len2 length of data2 in bytes, or UNIV_SQL_NULL
@return the comparison result of data1 and data2
@retval 0 if data1 is equal to data2
@retval negative if data1 is less than data2
@retval positive if data1 is greater than data2 */
int
cmp_data_data(
ulint mtype,
ulint prtype,
const byte* data1,
ulint len1,
const byte* data2,
ulint len2)
{
return(cmp_data(mtype, prtype, data1, len1, data2, len2));
}
/** Compare a data tuple to a physical record.
@param[in] dtuple data tuple
@param[in] rec B-tree record
@param[in] offsets rec_get_offsets(rec)
@param[in] n_cmp number of fields to compare
@param[in,out] matched_fields number of completely matched fields
@return the comparison result of dtuple and rec
@retval 0 if dtuple is equal to rec
@retval negative if dtuple is less than rec
@retval positive if dtuple is greater than rec */
int
cmp_dtuple_rec_with_match_low(
const dtuple_t* dtuple,
const rec_t* rec,
const rec_offs* offsets,
ulint n_cmp,
ulint* matched_fields)
{
ulint cur_field; /* current field number */
int ret; /* return value */
ut_ad(dtuple_check_typed(dtuple));
ut_ad(rec_offs_validate(rec, NULL, offsets));
cur_field = *matched_fields;
ut_ad(n_cmp > 0);
ut_ad(n_cmp <= dtuple_get_n_fields(dtuple));
ut_ad(cur_field <= n_cmp);
ut_ad(cur_field <= rec_offs_n_fields(offsets));
if (cur_field == 0) {
ulint rec_info = rec_get_info_bits(rec,
rec_offs_comp(offsets));
ulint tup_info = dtuple_get_info_bits(dtuple);
if (UNIV_UNLIKELY(rec_info & REC_INFO_MIN_REC_FLAG)) {
ret = !(tup_info & REC_INFO_MIN_REC_FLAG);
goto order_resolved;
} else if (UNIV_UNLIKELY(tup_info & REC_INFO_MIN_REC_FLAG)) {
ret = -1;
goto order_resolved;
}
}
/* Match fields in a loop */
for (; cur_field < n_cmp; cur_field++) {
const byte* rec_b_ptr;
const dfield_t* dtuple_field
= dtuple_get_nth_field(dtuple, cur_field);
const byte* dtuple_b_ptr
= static_cast<const byte*>(
dfield_get_data(dtuple_field));
const dtype_t* type
= dfield_get_type(dtuple_field);
ulint dtuple_f_len
= dfield_get_len(dtuple_field);
ulint rec_f_len;
/* We should never compare against an externally
stored field. Only clustered index records can
contain externally stored fields, and the first fields
(primary key fields) should already differ. */
ut_ad(!rec_offs_nth_extern(offsets, cur_field));
/* We should never compare against instantly added columns.
Columns can only be instantly added to clustered index
leaf page records, and the first fields (primary key fields)
should already differ. */
ut_ad(!rec_offs_nth_default(offsets, cur_field));
rec_b_ptr = rec_get_nth_field(rec, offsets, cur_field,
&rec_f_len);
ut_ad(!dfield_is_ext(dtuple_field));
ret = cmp_data(type->mtype, type->prtype,
dtuple_b_ptr, dtuple_f_len,
rec_b_ptr, rec_f_len);
if (ret) {
goto order_resolved;
}
}
ret = 0; /* If we ran out of fields, dtuple was equal to rec
up to the common fields */
order_resolved:
*matched_fields = cur_field;
return(ret);
}
/** Get the pad character code point for a type.
@param[in] type
@return pad character code point
@retval ULINT_UNDEFINED if no padding is specified */
UNIV_INLINE
ulint
cmp_get_pad_char(
const dtype_t* type)
{
switch (type->mtype) {
case DATA_FIXBINARY:
case DATA_BINARY:
if (dtype_get_charset_coll(type->prtype)
== DATA_MYSQL_BINARY_CHARSET_COLL) {
/* Starting from 5.0.18, do not pad
VARBINARY or BINARY columns. */
return(ULINT_UNDEFINED);
}
/* Fall through */
case DATA_CHAR:
case DATA_VARCHAR:
case DATA_MYSQL:
case DATA_VARMYSQL:
/* Space is the padding character for all char and binary
strings, and starting from 5.0.3, also for TEXT strings. */
return(0x20);
case DATA_GEOMETRY:
/* DATA_GEOMETRY is binary data, not ASCII-based. */
return(ULINT_UNDEFINED);
case DATA_BLOB:
if (!(type->prtype & DATA_BINARY_TYPE)) {
return(0x20);
}
/* Fall through */
default:
/* No padding specified */
return(ULINT_UNDEFINED);
}
}
/** Compare a data tuple to a physical record.
@param[in] dtuple data tuple
@param[in] rec B-tree or R-tree index record
@param[in] index index tree
@param[in] offsets rec_get_offsets(rec)
@param[in,out] matched_fields number of completely matched fields
@param[in,out] matched_bytes number of matched bytes in the first
field that is not matched
@return the comparison result of dtuple and rec
@retval 0 if dtuple is equal to rec
@retval negative if dtuple is less than rec
@retval positive if dtuple is greater than rec */
int
cmp_dtuple_rec_with_match_bytes(
const dtuple_t* dtuple,
const rec_t* rec,
const dict_index_t* index,
const rec_offs* offsets,
ulint* matched_fields,
ulint* matched_bytes)
{
ut_ad(dtuple_check_typed(dtuple));
ut_ad(rec_offs_validate(rec, index, offsets));
ut_ad(!(REC_INFO_MIN_REC_FLAG
& dtuple_get_info_bits(dtuple)));
if (UNIV_UNLIKELY(REC_INFO_MIN_REC_FLAG
& rec_get_info_bits(rec, rec_offs_comp(offsets)))) {
ut_ad(page_rec_is_first(rec, page_align(rec)));
ut_ad(!page_has_prev(page_align(rec)));
ut_ad(rec_is_metadata(rec, *index));
return 1;
}
ulint cur_field = *matched_fields;
ulint cur_bytes = *matched_bytes;
ulint n_cmp = dtuple_get_n_fields_cmp(dtuple);
int ret;
ut_ad(n_cmp <= dtuple_get_n_fields(dtuple));
ut_ad(cur_field <= n_cmp);
ut_ad(cur_field + (cur_bytes > 0) <= rec_offs_n_fields(offsets));
/* Match fields in a loop; stop if we run out of fields in dtuple
or find an externally stored field */
while (cur_field < n_cmp) {
const dfield_t* dfield = dtuple_get_nth_field(
dtuple, cur_field);
const dtype_t* type = dfield_get_type(dfield);
ulint dtuple_f_len = dfield_get_len(dfield);
const byte* dtuple_b_ptr;
const byte* rec_b_ptr;
ulint rec_f_len;
dtuple_b_ptr = static_cast<const byte*>(
dfield_get_data(dfield));
ut_ad(!rec_offs_nth_default(offsets, cur_field));
rec_b_ptr = rec_get_nth_field(rec, offsets,
cur_field, &rec_f_len);
ut_ad(!rec_offs_nth_extern(offsets, cur_field));
/* If we have matched yet 0 bytes, it may be that one or
both the fields are SQL null, or the record or dtuple may be
the predefined minimum record. */
if (cur_bytes == 0) {
if (dtuple_f_len == UNIV_SQL_NULL) {
if (rec_f_len == UNIV_SQL_NULL) {
goto next_field;
}
ret = -1;
goto order_resolved;
} else if (rec_f_len == UNIV_SQL_NULL) {
/* We define the SQL null to be the
smallest possible value of a field
in the alphabetical order */
ret = 1;
goto order_resolved;
}
}
switch (type->mtype) {
case DATA_FIXBINARY:
case DATA_BINARY:
case DATA_INT:
case DATA_SYS_CHILD:
case DATA_SYS:
break;
case DATA_BLOB:
if (type->prtype & DATA_BINARY_TYPE) {
break;
}
/* fall through */
default:
ret = cmp_data(type->mtype, type->prtype,
dtuple_b_ptr, dtuple_f_len,
rec_b_ptr, rec_f_len);
if (!ret) {
goto next_field;
}
cur_bytes = 0;
goto order_resolved;
}
/* Set the pointers at the current byte */
rec_b_ptr += cur_bytes;
dtuple_b_ptr += cur_bytes;
/* Compare then the fields */
for (const ulint pad = cmp_get_pad_char(type);;
cur_bytes++) {
ulint rec_byte = pad;
ulint dtuple_byte = pad;
if (rec_f_len <= cur_bytes) {
if (dtuple_f_len <= cur_bytes) {
goto next_field;
}
if (rec_byte == ULINT_UNDEFINED) {
ret = 1;
goto order_resolved;
}
} else {
rec_byte = *rec_b_ptr++;
}
if (dtuple_f_len <= cur_bytes) {
if (dtuple_byte == ULINT_UNDEFINED) {
ret = -1;
goto order_resolved;
}
} else {
dtuple_byte = *dtuple_b_ptr++;
}
if (dtuple_byte < rec_byte) {
ret = -1;
goto order_resolved;
} else if (dtuple_byte > rec_byte) {
ret = 1;
goto order_resolved;
}
}
next_field:
cur_field++;
cur_bytes = 0;
}
ut_ad(cur_bytes == 0);
ret = 0; /* If we ran out of fields, dtuple was equal to rec
up to the common fields */
order_resolved:
*matched_fields = cur_field;
*matched_bytes = cur_bytes;
return(ret);
}
/** Compare a data tuple to a physical record.
@see cmp_dtuple_rec_with_match
@param[in] dtuple data tuple
@param[in] rec B-tree record
@param[in] offsets rec_get_offsets(rec); may be NULL
for ROW_FORMAT=REDUNDANT
@return the comparison result of dtuple and rec
@retval 0 if dtuple is equal to rec
@retval negative if dtuple is less than rec
@retval positive if dtuple is greater than rec */
int
cmp_dtuple_rec(
const dtuple_t* dtuple,
const rec_t* rec,
const rec_offs* offsets)
{
ulint matched_fields = 0;
ut_ad(rec_offs_validate(rec, NULL, offsets));
return(cmp_dtuple_rec_with_match(dtuple, rec, offsets,
&matched_fields));
}
/**************************************************************//**
Checks if a dtuple is a prefix of a record. The last field in dtuple
is allowed to be a prefix of the corresponding field in the record.
@return TRUE if prefix */
ibool
cmp_dtuple_is_prefix_of_rec(
/*========================*/
const dtuple_t* dtuple, /*!< in: data tuple */
const rec_t* rec, /*!< in: physical record */
const rec_offs* offsets)/*!< in: array returned by rec_get_offsets() */
{
ulint n_fields;
ulint matched_fields = 0;
ut_ad(rec_offs_validate(rec, NULL, offsets));
n_fields = dtuple_get_n_fields(dtuple);
if (n_fields > rec_offs_n_fields(offsets)) {
ut_ad(0);
return(FALSE);
}
cmp_dtuple_rec_with_match(dtuple, rec, offsets, &matched_fields);
return(matched_fields == n_fields);
}
/*************************************************************//**
Compare two physical record fields.
@retval positive if rec1 field is greater than rec2
@retval negative if rec1 field is less than rec2
@retval 0 if rec1 field equals to rec2 */
static MY_ATTRIBUTE((nonnull, warn_unused_result))
int
cmp_rec_rec_simple_field(
/*=====================*/
const rec_t* rec1, /*!< in: physical record */
const rec_t* rec2, /*!< in: physical record */
const rec_offs* offsets1,/*!< in: rec_get_offsets(rec1, ...) */
const rec_offs* offsets2,/*!< in: rec_get_offsets(rec2, ...) */
const dict_index_t* index, /*!< in: data dictionary index */
ulint n) /*!< in: field to compare */
{
const byte* rec1_b_ptr;
const byte* rec2_b_ptr;
ulint rec1_f_len;
ulint rec2_f_len;
const dict_col_t* col = dict_index_get_nth_col(index, n);
ut_ad(!rec_offs_nth_extern(offsets1, n));
ut_ad(!rec_offs_nth_extern(offsets2, n));
rec1_b_ptr = rec_get_nth_field(rec1, offsets1, n, &rec1_f_len);
rec2_b_ptr = rec_get_nth_field(rec2, offsets2, n, &rec2_f_len);
return(cmp_data(col->mtype, col->prtype,
rec1_b_ptr, rec1_f_len, rec2_b_ptr, rec2_f_len));
}
/** Compare two physical records that contain the same number of columns,
none of which are stored externally.
@retval positive if rec1 (including non-ordering columns) is greater than rec2
@retval negative if rec1 (including non-ordering columns) is less than rec2
@retval 0 if rec1 is a duplicate of rec2 */
int
cmp_rec_rec_simple(
/*===============*/
const rec_t* rec1, /*!< in: physical record */
const rec_t* rec2, /*!< in: physical record */
const rec_offs* offsets1,/*!< in: rec_get_offsets(rec1, ...) */
const rec_offs* offsets2,/*!< in: rec_get_offsets(rec2, ...) */
const dict_index_t* index, /*!< in: data dictionary index */
struct TABLE* table) /*!< in: MySQL table, for reporting
duplicate key value if applicable,
or NULL */
{
ulint n;
ulint n_uniq = dict_index_get_n_unique(index);
bool null_eq = false;
ut_ad(rec_offs_n_fields(offsets1) >= n_uniq);
ut_ad(rec_offs_n_fields(offsets2) == rec_offs_n_fields(offsets2));
ut_ad(rec_offs_comp(offsets1) == rec_offs_comp(offsets2));
for (n = 0; n < n_uniq; n++) {
int cmp = cmp_rec_rec_simple_field(
rec1, rec2, offsets1, offsets2, index, n);
if (cmp) {
return(cmp);
}
/* If the fields are internally equal, they must both
be NULL or non-NULL. */
ut_ad(rec_offs_nth_sql_null(offsets1, n)
== rec_offs_nth_sql_null(offsets2, n));
if (rec_offs_nth_sql_null(offsets1, n)) {
ut_ad(!(dict_index_get_nth_col(index, n)->prtype
& DATA_NOT_NULL));
null_eq = true;
}
}
/* If we ran out of fields, the ordering columns of rec1 were
equal to rec2. Issue a duplicate key error if needed. */
if (!null_eq && table && dict_index_is_unique(index)) {
/* Report erroneous row using new version of table. */
innobase_rec_to_mysql(table, rec1, index, offsets1);
return(0);
}
/* Else, keep comparing so that we have the full internal
order. */
for (; n < dict_index_get_n_fields(index); n++) {
int cmp = cmp_rec_rec_simple_field(
rec1, rec2, offsets1, offsets2, index, n);
if (cmp) {
return(cmp);
}
/* If the fields are internally equal, they must both
be NULL or non-NULL. */
ut_ad(rec_offs_nth_sql_null(offsets1, n)
== rec_offs_nth_sql_null(offsets2, n));
}
/* This should never be reached. Internally, an index must
never contain duplicate entries. */
ut_ad(0);
return(0);
}
/** Compare two B-tree or R-tree records.
Only the common first fields are compared, and externally stored field
are treated as equal.
@param[in] rec1 record (possibly not on an index page)
@param[in] rec2 B-tree or R-tree record in an index page
@param[in] offsets1 rec_get_offsets(rec1, index)
@param[in] offsets2 rec_get_offsets(rec2, index)
@param[in] nulls_unequal true if this is for index cardinality
statistics estimation with
innodb_stats_method=nulls_unequal
or innodb_stats_method=nulls_ignored
@param[out] matched_fields number of completely matched fields
within the first field not completely matched
@retval 0 if rec1 is equal to rec2
@retval negative if rec1 is less than rec2
@retval positive if rec1 is greater than rec2 */
int
cmp_rec_rec(
const rec_t* rec1,
const rec_t* rec2,
const rec_offs* offsets1,
const rec_offs* offsets2,
const dict_index_t* index,
bool nulls_unequal,
ulint* matched_fields)
{
ulint rec1_f_len; /* length of current field in rec */
const byte* rec1_b_ptr; /* pointer to the current byte
in rec field */
ulint rec2_f_len; /* length of current field in rec */
const byte* rec2_b_ptr; /* pointer to the current byte
in rec field */
ulint cur_field = 0; /* current field number */
int ret = 0; /* return value */
ut_ad(rec1 != NULL);
ut_ad(rec2 != NULL);
ut_ad(index != NULL);
ut_ad(rec_offs_validate(rec1, index, offsets1));
ut_ad(rec_offs_validate(rec2, index, offsets2));
ut_ad(rec_offs_comp(offsets1) == rec_offs_comp(offsets2));
ut_ad(fil_page_index_page_check(page_align(rec2)));
ut_ad(!!dict_index_is_spatial(index)
== (fil_page_get_type(page_align(rec2)) == FIL_PAGE_RTREE));
ulint comp = rec_offs_comp(offsets1);
ulint n_fields;
/* Test if rec is the predefined minimum record */
if (UNIV_UNLIKELY(rec_get_info_bits(rec1, comp)
& REC_INFO_MIN_REC_FLAG)) {
ret = UNIV_UNLIKELY(rec_get_info_bits(rec2, comp)
& REC_INFO_MIN_REC_FLAG)
? 0 : -1;
goto order_resolved;
} else if (UNIV_UNLIKELY
(rec_get_info_bits(rec2, comp)
& REC_INFO_MIN_REC_FLAG)) {
ret = 1;
goto order_resolved;
}
/* For non-leaf spatial index records, the
dict_index_get_n_unique_in_tree() does include the child page
number, because spatial index node pointers only contain
the MBR (minimum bounding rectangle) and the child page number.
For B-tree node pointers, the key alone (secondary index
columns and PRIMARY KEY columns) must be unique, and there is
no need to compare the child page number. */
n_fields = std::min(rec_offs_n_fields(offsets1),
rec_offs_n_fields(offsets2));
n_fields = std::min<ulint>(n_fields,
dict_index_get_n_unique_in_tree(index));
for (; cur_field < n_fields; cur_field++) {
ulint mtype;
ulint prtype;
if (UNIV_UNLIKELY(dict_index_is_ibuf(index))) {
/* This is for the insert buffer B-tree. */
mtype = DATA_BINARY;
prtype = 0;
} else {
const dict_col_t* col = dict_index_get_nth_col(
index, cur_field);
mtype = col->mtype;
prtype = col->prtype;
if (UNIV_LIKELY(!dict_index_is_spatial(index))) {
} else if (cur_field == 0) {
ut_ad(DATA_GEOMETRY_MTYPE(mtype));
prtype |= DATA_GIS_MBR;
} else if (!page_rec_is_leaf(rec2)) {
/* Compare the child page number. */
ut_ad(cur_field == 1);
mtype = DATA_SYS_CHILD;
prtype = 0;
}
}
/* We should never encounter an externally stored field.
Externally stored fields only exist in clustered index
leaf page records. These fields should already differ
in the primary key columns already, before DB_TRX_ID,
DB_ROLL_PTR, and any externally stored columns. */
ut_ad(!rec_offs_nth_extern(offsets1, cur_field));
ut_ad(!rec_offs_nth_extern(offsets2, cur_field));
ut_ad(!rec_offs_nth_default(offsets1, cur_field));
ut_ad(!rec_offs_nth_default(offsets2, cur_field));
rec1_b_ptr = rec_get_nth_field(rec1, offsets1,
cur_field, &rec1_f_len);
rec2_b_ptr = rec_get_nth_field(rec2, offsets2,
cur_field, &rec2_f_len);
if (nulls_unequal
&& rec1_f_len == UNIV_SQL_NULL
&& rec2_f_len == UNIV_SQL_NULL) {
ret = -1;
goto order_resolved;
}
ret = cmp_data(mtype, prtype,
rec1_b_ptr, rec1_f_len,
rec2_b_ptr, rec2_f_len);
if (ret) {
goto order_resolved;
}
}
/* If we ran out of fields, rec1 was equal to rec2 up
to the common fields */
ut_ad(ret == 0);
order_resolved:
if (matched_fields) {
*matched_fields = cur_field;
}
return ret;
}
#ifdef UNIV_COMPILE_TEST_FUNCS
#ifdef HAVE_UT_CHRONO_T
void
test_cmp_data_data(ulint len)
{
int i;
static byte zeros[64];
if (len > sizeof zeros) {
len = sizeof zeros;
}
ut_chrono_t ch(__func__);
for (i = 1000000; i > 0; i--) {
i += cmp_data(DATA_INT, 0, zeros, len, zeros, len);
}
}
#endif /* HAVE_UT_CHRONO_T */
#endif /* UNIV_COMPILE_TEST_FUNCS */
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