📄 rem0cmp.h
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/***********************************************************************Comparison services for records(c) 1994-2001 Innobase OyCreated 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 types are equal for comparison purposes. */iboolcmp_types_are_equal(/*================*/ /* out: TRUE if the types are considered equal in comparisons */ dtype_t* type1, /* in: type 1 */ dtype_t* type2, /* in: type 2 */ ibool check_charsets); /* in: whether to check charsets *//*****************************************************************This function is used to compare two data fields for which we know thedata type. */UNIV_INLINEintcmp_data_data(/*==========*/ /* out: 1, 0, -1, if data1 is greater, equal, less than data2, respectively */ dtype_t* cur_type,/* in: data type of the fields */ byte* data1, /* in: data field (== a pointer to a memory buffer) */ ulint len1, /* in: data field length or UNIV_SQL_NULL */ 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 thedata type. */intcmp_data_data_slow(/*===============*/ /* out: 1, 0, -1, if data1 is greater, equal, less than data2, respectively */ dtype_t* cur_type,/* in: data type of the fields */ byte* data1, /* in: data field (== a pointer to a memory buffer) */ ulint len1, /* in: data field length or UNIV_SQL_NULL */ 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 firsthas its data type field set. */UNIV_INLINEintcmp_dfield_dfield(/*==============*/ /* out: 1, 0, -1, if dfield1 is greater, equal, less than dfield2, respectively */ dfield_t* dfield1,/* in: data field; must have type field set */ 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 forthe the data tuple! If we denote by n = n_fields_cmp, then rec musthave either m >= n fields, or it must differ from dtuple in some ofthe m fields rec has. If rec has an externally stored field we do notcompare it but return with value 0 if such a comparison should bemade. */intcmp_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 */ dtuple_t* dtuple, /* in: data tuple */ 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. */intcmp_dtuple_rec(/*===========*/ /* out: 1, 0, -1, if dtuple is greater, equal, less than rec, respectively; see the comments for cmp_dtuple_rec_with_match */ dtuple_t* dtuple, /* in: data tuple */ 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 dtupleis allowed to be a prefix of the corresponding field in the record. */iboolcmp_dtuple_is_prefix_of_rec(/*========================*/ /* out: TRUE if prefix */ dtuple_t* dtuple, /* in: data tuple */ 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 commonfirst fields are compared, and if an externally stored field isencountered, then 0 is returned. */intcmp_rec_rec_with_match(/*===================*/ /* out: 1, 0 , -1 if rec1 is greater, equal, less, respectively, than rec2; only the common first fields are compared */ rec_t* rec1, /* in: physical record */ 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 commonfirst fields are compared. */UNIV_INLINEintcmp_rec_rec(/*========*/ /* out: 1, 0 , -1 if rec1 is greater, equal, less, respectively, than rec2; only the common first fields are compared */ rec_t* rec1, /* in: physical record */ 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
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