rem0cmp.h

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/** @file include/rem0cmp.h
 Comparison services for records
 
 Created 7/1/1994 Heikki Tuuri
 ************************************************************************/
 
#ifndef rem0cmp_h
#define rem0cmp_h
 
#include <my_sys.h>
#include "data0data.h"
#include "data0type.h"
#include "dict0dict.h"
#include "ha_prototypes.h"
#include "rem0rec.h"
 
/** Disable the min flag during row comparisons. */
constexpr auto DISABLE_MIN_REC_FLAG_CHECK = ULINT_UNDEFINED;
 
// Forward declaration
namespace dd {
class Spatial_reference_system;
}
 
/** Returns true if two columns are equal for comparison purposes.
@param[in] col1 Column to compare.
@param[in] col2 Column to compare.
@param[in] check_charsets if true then check the character sets.
@return true if the columns are considered equal in comparisons. */
bool cmp_cols_are_equal(const dict_col_t *col1, const dict_col_t *col2,
                        bool check_charsets);
 
/*!< in: whether to check charsets */
/** Compare two data fields.
@param[in]      mtype   main type
@param[in]      prtype  precise type
@param[in]      is_asc  true=ascending, false=descending order
@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 */
[[nodiscard]] int cmp_data_data(ulint mtype, ulint prtype, bool is_asc,
                                const byte *data1, ulint len1,
                                const byte *data2, ulint len2);
 
/** Compare two data fields.
@param[in]      dfield1 data field; must have type field set
@param[in]      dfield2 data field
@param[in]      is_asc  true=ASC, false=DESC
@return the comparison result of dfield1 and dfield2
@retval 0 if dfield1 is equal to dfield2
@retval negative if dfield1 is less than dfield2
@retval positive if dfield1 is greater than dfield2 */
[[nodiscard]] static inline int cmp_dfield_dfield(const dfield_t *dfield1,
                                                  const dfield_t *dfield2,
                                                  bool is_asc);
 
/** Compare two data fields, the first one can be of any form of multi-value
field, while the second one must be one field from multi-value index
@param[in]      dfield1 multi-value data field;
@param[in]      dfield2 data field; must have type field set
@return 0 if dfield1 has dfield2 or they are equal if both NULL, otherwise 1 */
[[nodiscard]] static inline int cmp_multi_value_dfield_dfield(
    const dfield_t *dfield1, const dfield_t *dfield2);
 
/** Compare a GIS 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] mode compare mode
@param[in] srs Spatial reference system of R-tree
@retval negative if dtuple is less than rec */
int cmp_dtuple_rec_with_gis(const dtuple_t *dtuple, const rec_t *rec,
                            const ulint *offsets, page_cur_mode_t mode,
                            const dd::Spatial_reference_system *srs);
 
/** Compare a GIS data tuple to a physical record in rtree non-leaf node.
We need to check the page number field, since we don't store pk field in
rtree non-leaf node.
@param[in]      dtuple  data tuple
@param[in]      rec     R-tree record
@param[in]      offsets rec_get_offsets(rec)
@param[in]  srs Spatial referenxe system
@retval negative if dtuple is less than rec */
int cmp_dtuple_rec_with_gis_internal(const dtuple_t *dtuple, const rec_t *rec,
                                     const ulint *offsets,
                                     const dd::Spatial_reference_system *srs);
 
/** Compare a data tuple to a physical record.
@param[in]      dtuple          data tuple
@param[in]      rec             record
@param[in]      index           index
@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 dict_index_t *index,
                                  const ulint *offsets, ulint n_cmp,
                                  ulint *matched_fields);
 
/** 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 */
[[nodiscard]] int cmp_dtuple_rec_with_match_bytes(
    const dtuple_t *dtuple, const rec_t *rec, const dict_index_t *index,
    const ulint *offsets, ulint *matched_fields, ulint *matched_bytes);
/** Compare a data tuple to a physical record.
@see cmp_dtuple_rec_with_match
@param[in]      dtuple  data tuple
@param[in]      rec     record
@param[in]      index   index
@param[in]      offsets rec_get_offsets(rec)
@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 */
[[nodiscard]] int cmp_dtuple_rec(const dtuple_t *dtuple, const rec_t *rec,
                                 const dict_index_t *index,
                                 const ulint *offsets);
/** Check if a dtuple is a prefix of a record.
@param[in]      dtuple  data tuple
@param[in]      rec     B-tree record
@param[in]      index   B-tree index
@param[in]      offsets rec_get_offsets(rec)
@return true if prefix */
[[nodiscard]] bool cmp_dtuple_is_prefix_of_rec(const dtuple_t *dtuple,
                                               const rec_t *rec,
                                               const dict_index_t *index,
                                               const ulint *offsets);
/** Compare two physical records that contain the same number of columns,
none of which are stored externally.
@param[in] rec1 Physical record 1 to compare
@param[in] rec2 Physical record 2 to compare
@param[in] offsets1 rec_get_offsets(rec1, ...)
@param[in] offsets2 rec_get_offsets(rec2, ...)
@param[in] index Data dictionary index
@param[in] table MySQL table, for reporting duplicate key value if applicable,
or nullptr
@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 */
[[nodiscard]] int cmp_rec_rec_simple(const rec_t *rec1, const rec_t *rec2,
                                     const ulint *offsets1,
                                     const ulint *offsets2,
                                     const dict_index_t *index,
                                     struct TABLE *table);
/** Compare two B-tree records.
@param[in] rec1 B-tree record
@param[in] rec2 B-tree record
@param[in] offsets1 rec_get_offsets(rec1, index)
@param[in] offsets2 rec_get_offsets(rec2, index)
@param[in] index B-tree index
@param[in] spatial_index_non_leaf true if record is in spatial non leaf page
@param[in] nulls_unequal true if this is for index cardinality
statistics estimation, and 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
@param[in] cmp_btree_recs true if we're comparing two b-tree records
@return the comparison result
@retval 0 if rec1 is equal to rec2
@retval negative if rec1 is less than rec2
@retval positive if rec2 is greater than rec2 */
int cmp_rec_rec_with_match(const rec_t *rec1, const rec_t *rec2,
                           const ulint *offsets1, const ulint *offsets2,
                           const dict_index_t *index,
                           bool spatial_index_non_leaf, bool nulls_unequal,
                           ulint *matched_fields, bool cmp_btree_recs = true);
 
/** Compare two B-tree records.
Only the common first fields are compared, and externally stored field
are treated as equal.
@param[in]      rec1                    B-tree record
@param[in]      rec2                    B-tree record
@param[in]      offsets1                rec_get_offsets(rec1, index)
@param[in]      offsets2                rec_get_offsets(rec2, index)
@param[in]      index                   B-tree index
@param[in]      spatial_index_non_leaf  true if spatial index non leaf records
@param[out]     matched_fields  number of completely matched fields
within the first field not completely matched
@param[in]  cmp_btree_recs  true if the both the records are b-tree records
@return positive, 0, negative if rec1 is greater, equal, less, than rec2,
respectively */
static inline int cmp_rec_rec(const rec_t *rec1, const rec_t *rec2,
                              const ulint *offsets1, const ulint *offsets2,
                              const dict_index_t *index,
                              bool spatial_index_non_leaf,
                              ulint *matched_fields = nullptr,
                              bool cmp_btree_recs = true);
 
#ifndef UNIV_HOTBACKUP
/** Compare two data fields.
@param[in] dfield1 data field
@param[in] dfield2 data field
@return the comparison result of dfield1 and dfield2
@retval true if dfield1 is equal to dfield2, or a prefix of dfield1
@retval false otherwise */
[[nodiscard]] static inline bool cmp_dfield_dfield_eq_prefix(
    const dfield_t *dfield1, const dfield_t *dfield2);
#endif /* !UNIV_HOTBACKUP */
 
#include "rem0cmp.ic"
 
#endif