mariadb/include/rem0cmp.h
marko 8f07794024 branches/zip: Introduce const qualifiers to many read-only parameters
and modify some functions to return const pointers.  Add const qualifiers
to local variable declarations or casts to remove the const qualifier
in those places where write access is needed.
2006-10-17 12:24:13 +00:00

173 lines
6.4 KiB
C

/***********************************************************************
Comparison services for records
(c) 1994-2001 Innobase Oy
Created 7/1/1994 Heikki Tuuri
************************************************************************/
#ifndef rem0cmp_h
#define rem0cmp_h
#include "univ.i"
#include "data0data.h"
#include "data0type.h"
#include "dict0dict.h"
#include "rem0rec.h"
/*****************************************************************
Returns TRUE if two columns are equal for comparison purposes. */
ibool
cmp_cols_are_equal(
/*===============*/
/* out: TRUE if the columns are
considered equal in comparisons */
const dict_col_t* col1, /* in: column 1 */
const dict_col_t* col2, /* in: column 2 */
ibool check_charsets);
/* in: whether to check charsets */
/*****************************************************************
This function is used to compare two data fields for which we know the
data type. */
UNIV_INLINE
int
cmp_data_data(
/*==========*/
/* out: 1, 0, -1, if data1 is greater, equal,
less than data2, respectively */
ulint mtype, /* in: main type */
ulint prtype, /* in: precise type */
const byte* data1, /* in: data field (== a pointer to a memory
buffer) */
ulint len1, /* in: data field length or UNIV_SQL_NULL */
const byte* data2, /* in: data field (== a pointer to a memory
buffer) */
ulint len2); /* in: data field length or UNIV_SQL_NULL */
/*****************************************************************
This function is used to compare two data fields for which we know the
data type. */
int
cmp_data_data_slow(
/*===============*/
/* out: 1, 0, -1, if data1 is greater, equal,
less than data2, respectively */
ulint mtype, /* in: main type */
ulint prtype, /* in: precise type */
const byte* data1, /* in: data field (== a pointer to a memory
buffer) */
ulint len1, /* in: data field length or UNIV_SQL_NULL */
const byte* data2, /* in: data field (== a pointer to a memory
buffer) */
ulint len2); /* in: data field length or UNIV_SQL_NULL */
/*****************************************************************
This function is used to compare two dfields where at least the first
has its data type field set. */
UNIV_INLINE
int
cmp_dfield_dfield(
/*==============*/
/* out: 1, 0, -1, if dfield1 is greater, equal,
less than dfield2, respectively */
const dfield_t* dfield1,/* in: data field; must have type field set */
const dfield_t* dfield2);/* in: data field */
/*****************************************************************
This function is used to compare a data tuple to a physical record.
Only dtuple->n_fields_cmp first fields are taken into account for
the the data tuple! If we denote by n = n_fields_cmp, then rec must
have either m >= n fields, or it must differ from dtuple in some of
the m fields rec has. If rec has an externally stored field we do not
compare it but return with value 0 if such a comparison should be
made. */
int
cmp_dtuple_rec_with_match(
/*======================*/
/* out: 1, 0, -1, if dtuple is greater, equal,
less than rec, respectively, when only the
common first fields are compared, or
until the first externally stored field in
rec */
const dtuple_t* dtuple, /* in: data tuple */
const rec_t* rec, /* in: physical record which differs from
dtuple in some of the common fields, or which
has an equal number or more fields than
dtuple */
const ulint* offsets,/* in: array returned by rec_get_offsets() */
ulint* matched_fields, /* in/out: number of already completely
matched fields; when function returns,
contains the value for current comparison */
ulint* matched_bytes); /* in/out: number of already matched
bytes within the first field not completely
matched; when function returns, contains the
value for current comparison */
/******************************************************************
Compares a data tuple to a physical record. */
int
cmp_dtuple_rec(
/*===========*/
/* out: 1, 0, -1, if dtuple is greater, equal,
less than rec, respectively; see the comments
for cmp_dtuple_rec_with_match */
const dtuple_t* dtuple, /* in: data tuple */
const rec_t* rec, /* in: physical record */
const ulint* offsets);/* in: array returned by rec_get_offsets() */
/******************************************************************
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. */
ibool
cmp_dtuple_is_prefix_of_rec(
/*========================*/
/* out: TRUE if prefix */
const dtuple_t* dtuple, /* in: data tuple */
const rec_t* rec, /* in: physical record */
const ulint* offsets);/* in: array returned by rec_get_offsets() */
/*****************************************************************
This function is used to compare two physical records. Only the common
first fields are compared, and if an externally stored field is
encountered, then 0 is returned. */
int
cmp_rec_rec_with_match(
/*===================*/
/* out: 1, 0 , -1 if rec1 is greater, equal,
less, respectively, than rec2; only the common
first fields are compared */
const rec_t* rec1, /* in: physical record */
const rec_t* rec2, /* in: physical record */
const ulint* offsets1,/* in: rec_get_offsets(rec1, index) */
const ulint* offsets2,/* in: rec_get_offsets(rec2, index) */
dict_index_t* index, /* in: data dictionary index */
ulint* matched_fields, /* in/out: number of already completely
matched fields; when the function returns,
contains the value the for current
comparison */
ulint* matched_bytes);/* in/out: number of already matched
bytes within the first field not completely
matched; when the function returns, contains
the value for the current comparison */
/*****************************************************************
This function is used to compare two physical records. Only the common
first fields are compared. */
UNIV_INLINE
int
cmp_rec_rec(
/*========*/
/* out: 1, 0 , -1 if rec1 is greater, equal,
less, respectively, than rec2; only the common
first fields are compared */
const rec_t* rec1, /* in: physical record */
const rec_t* rec2, /* in: physical record */
const ulint* offsets1,/* in: rec_get_offsets(rec1, index) */
const ulint* offsets2,/* in: rec_get_offsets(rec2, index) */
dict_index_t* index); /* in: data dictionary index */
#ifndef UNIV_NONINL
#include "rem0cmp.ic"
#endif
#endif