/***************************************************************************** Copyright (c) 1994, 2009, Innobase Oy. All Rights Reserved. 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA *****************************************************************************/ /**************************************************//** @file include/btr0cur.h The index tree cursor Created 10/16/1994 Heikki Tuuri *******************************************************/ #ifndef btr0cur_h #define btr0cur_h #include "univ.i" #include "dict0dict.h" #include "page0cur.h" #include "btr0types.h" /* Mode flags for btr_cur operations; these can be ORed */ #define BTR_NO_UNDO_LOG_FLAG 1 /* do no undo logging */ #define BTR_NO_LOCKING_FLAG 2 /* do no record lock checking */ #define BTR_KEEP_SYS_FLAG 4 /* sys fields will be found from the update vector or inserted entry */ #ifndef UNIV_HOTBACKUP #include "que0types.h" #include "row0types.h" #include "ha0ha.h" #define BTR_CUR_ADAPT #define BTR_CUR_HASH_ADAPT #ifdef UNIV_DEBUG /*********************************************************//** Returns the page cursor component of a tree cursor. @return pointer to page cursor component */ UNIV_INLINE page_cur_t* btr_cur_get_page_cur( /*=================*/ const btr_cur_t* cursor);/*!< in: tree cursor */ #else /* UNIV_DEBUG */ # define btr_cur_get_page_cur(cursor) (&(cursor)->page_cur) #endif /* UNIV_DEBUG */ /*********************************************************//** Returns the buffer block on which the tree cursor is positioned. @return pointer to buffer block */ UNIV_INLINE buf_block_t* btr_cur_get_block( /*==============*/ btr_cur_t* cursor);/*!< in: tree cursor */ /*********************************************************//** Returns the record pointer of a tree cursor. @return pointer to record */ UNIV_INLINE rec_t* btr_cur_get_rec( /*============*/ btr_cur_t* cursor);/*!< in: tree cursor */ /*********************************************************//** Returns the compressed page on which the tree cursor is positioned. @return pointer to compressed page, or NULL if the page is not compressed */ UNIV_INLINE page_zip_des_t* btr_cur_get_page_zip( /*=================*/ btr_cur_t* cursor);/*!< in: tree cursor */ /*********************************************************//** Invalidates a tree cursor by setting record pointer to NULL. */ UNIV_INLINE void btr_cur_invalidate( /*===============*/ btr_cur_t* cursor);/*!< in: tree cursor */ /*********************************************************//** Returns the page of a tree cursor. @return pointer to page */ UNIV_INLINE page_t* btr_cur_get_page( /*=============*/ btr_cur_t* cursor);/*!< in: tree cursor */ /*********************************************************//** Returns the index of a cursor. @return index */ UNIV_INLINE dict_index_t* btr_cur_get_index( /*==============*/ btr_cur_t* cursor);/*!< in: B-tree cursor */ /*********************************************************//** Positions a tree cursor at a given record. */ UNIV_INLINE void btr_cur_position( /*=============*/ dict_index_t* index, /*!< in: index */ rec_t* rec, /*!< in: record in tree */ buf_block_t* block, /*!< in: buffer block of rec */ btr_cur_t* cursor);/*!< in: cursor */ /********************************************************************//** Searches an index tree and positions a tree cursor on a given level. NOTE: n_fields_cmp in tuple must be set so that it cannot be compared to node pointer page number fields on the upper levels of the tree! Note that if mode is PAGE_CUR_LE, which is used in inserts, then cursor->up_match and cursor->low_match both will have sensible values. If mode is PAGE_CUR_GE, then up_match will a have a sensible value. */ UNIV_INTERN void btr_cur_search_to_nth_level( /*========================*/ dict_index_t* index, /*!< in: index */ ulint level, /*!< in: the tree level of search */ const dtuple_t* tuple, /*!< in: data tuple; NOTE: n_fields_cmp in tuple must be set so that it cannot get compared to the node ptr page number field! */ ulint mode, /*!< in: PAGE_CUR_L, ...; NOTE that if the search is made using a unique prefix of a record, mode should be PAGE_CUR_LE, not PAGE_CUR_GE, as the latter may end up on the previous page of the record! Inserts should always be made using PAGE_CUR_LE to search the position! */ ulint latch_mode, /*!< in: BTR_SEARCH_LEAF, ..., ORed with BTR_INSERT and BTR_ESTIMATE; cursor->left_block is used to store a pointer to the left neighbor page, in the cases BTR_SEARCH_PREV and BTR_MODIFY_PREV; NOTE that if has_search_latch is != 0, we maybe do not have a latch set on the cursor page, we assume the caller uses his search latch to protect the record! */ btr_cur_t* cursor, /*!< in/out: tree cursor; the cursor page is s- or x-latched, but see also above! */ ulint has_search_latch,/*!< in: latch mode the caller currently has on btr_search_latch: RW_S_LATCH, or 0 */ mtr_t* mtr); /*!< in: mtr */ /*****************************************************************//** Opens a cursor at either end of an index. */ UNIV_INTERN void btr_cur_open_at_index_side( /*=======================*/ ibool from_left, /*!< in: TRUE if open to the low end, FALSE if to the high end */ dict_index_t* index, /*!< in: index */ ulint latch_mode, /*!< in: latch mode */ btr_cur_t* cursor, /*!< in: cursor */ mtr_t* mtr); /*!< in: mtr */ /**********************************************************************//** Positions a cursor at a randomly chosen position within a B-tree. */ UNIV_INTERN void btr_cur_open_at_rnd_pos( /*====================*/ dict_index_t* index, /*!< in: index */ ulint latch_mode, /*!< in: BTR_SEARCH_LEAF, ... */ btr_cur_t* cursor, /*!< in/out: B-tree cursor */ mtr_t* mtr); /*!< in: mtr */ /*************************************************************//** Tries to perform an insert to a page in an index tree, next to cursor. It is assumed that mtr holds an x-latch on the page. The operation does not succeed if there is too little space on the page. If there is just one record on the page, the insert will always succeed; this is to prevent trying to split a page with just one record. @return DB_SUCCESS, DB_WAIT_LOCK, DB_FAIL, or error number */ UNIV_INTERN ulint btr_cur_optimistic_insert( /*======================*/ ulint flags, /*!< in: undo logging and locking flags: if not zero, the parameters index and thr should be specified */ btr_cur_t* cursor, /*!< in: cursor on page after which to insert; cursor stays valid */ dtuple_t* entry, /*!< in/out: entry to insert */ rec_t** rec, /*!< out: pointer to inserted record if succeed */ big_rec_t** big_rec,/*!< out: big rec vector whose fields have to be stored externally by the caller, or NULL */ ulint n_ext, /*!< in: number of externally stored columns */ que_thr_t* thr, /*!< in: query thread or NULL */ mtr_t* mtr); /*!< in: mtr; if this function returns DB_SUCCESS on a leaf page of a secondary index in a compressed tablespace, the mtr must be committed before latching any further pages */ /*************************************************************//** Performs an insert on a page of an index tree. It is assumed that mtr holds an x-latch on the tree and on the cursor page. If the insert is made on the leaf level, to avoid deadlocks, mtr must also own x-latches to brothers of page, if those brothers exist. @return DB_SUCCESS or error number */ UNIV_INTERN ulint btr_cur_pessimistic_insert( /*=======================*/ ulint flags, /*!< in: undo logging and locking flags: if not zero, the parameter thr should be specified; if no undo logging is specified, then the caller must have reserved enough free extents in the file space so that the insertion will certainly succeed */ btr_cur_t* cursor, /*!< in: cursor after which to insert; cursor stays valid */ dtuple_t* entry, /*!< in/out: entry to insert */ rec_t** rec, /*!< out: pointer to inserted record if succeed */ big_rec_t** big_rec,/*!< out: big rec vector whose fields have to be stored externally by the caller, or NULL */ ulint n_ext, /*!< in: number of externally stored columns */ que_thr_t* thr, /*!< in: query thread or NULL */ mtr_t* mtr); /*!< in: mtr */ /*************************************************************//** Updates a record when the update causes no size changes in its fields. @return DB_SUCCESS or error number */ UNIV_INTERN ulint btr_cur_update_in_place( /*====================*/ ulint flags, /*!< in: undo logging and locking flags */ btr_cur_t* cursor, /*!< in: cursor on the record to update; cursor stays valid and positioned on the same record */ const upd_t* update, /*!< in: update vector */ ulint cmpl_info,/*!< in: compiler info on secondary index updates */ que_thr_t* thr, /*!< in: query thread */ mtr_t* mtr); /*!< in: mtr; must be committed before latching any further pages */ /*************************************************************//** Tries to update a record on a page in an index tree. It is assumed that mtr holds an x-latch on the page. The operation does not succeed if there is too little space on the page or if the update would result in too empty a page, so that tree compression is recommended. @return DB_SUCCESS, or DB_OVERFLOW if the updated record does not fit, DB_UNDERFLOW if the page would become too empty, or DB_ZIP_OVERFLOW if there is not enough space left on the compressed page */ UNIV_INTERN ulint btr_cur_optimistic_update( /*======================*/ ulint flags, /*!< in: undo logging and locking flags */ btr_cur_t* cursor, /*!< in: cursor on the record to update; cursor stays valid and positioned on the same record */ const upd_t* update, /*!< in: update vector; this must also contain trx id and roll ptr fields */ ulint cmpl_info,/*!< in: compiler info on secondary index updates */ que_thr_t* thr, /*!< in: query thread */ mtr_t* mtr); /*!< in: mtr; must be committed before latching any further pages */ /*************************************************************//** Performs an update of a record on a page of a tree. It is assumed that mtr holds an x-latch on the tree and on the cursor page. If the update is made on the leaf level, to avoid deadlocks, mtr must also own x-latches to brothers of page, if those brothers exist. @return DB_SUCCESS or error code */ UNIV_INTERN ulint btr_cur_pessimistic_update( /*=======================*/ ulint flags, /*!< in: undo logging, locking, and rollback flags */ btr_cur_t* cursor, /*!< in: cursor on the record to update */ mem_heap_t** heap, /*!< in/out: pointer to memory heap, or NULL */ big_rec_t** big_rec,/*!< out: big rec vector whose fields have to be stored externally by the caller, or NULL */ const upd_t* update, /*!< in: update vector; this is allowed also contain trx id and roll ptr fields, but the values in update vector have no effect */ ulint cmpl_info,/*!< in: compiler info on secondary index updates */ que_thr_t* thr, /*!< in: query thread */ mtr_t* mtr); /*!< in: mtr; must be committed before latching any further pages */ /***********************************************************//** Marks a clustered index record deleted. Writes an undo log record to undo log on this delete marking. Writes in the trx id field the id of the deleting transaction, and in the roll ptr field pointer to the undo log record created. @return DB_SUCCESS, DB_LOCK_WAIT, or error number */ UNIV_INTERN ulint btr_cur_del_mark_set_clust_rec( /*===========================*/ ulint flags, /*!< in: undo logging and locking flags */ btr_cur_t* cursor, /*!< in: cursor */ ibool val, /*!< in: value to set */ que_thr_t* thr, /*!< in: query thread */ mtr_t* mtr); /*!< in: mtr */ /***********************************************************//** Sets a secondary index record delete mark to TRUE or FALSE. @return DB_SUCCESS, DB_LOCK_WAIT, or error number */ UNIV_INTERN ulint btr_cur_del_mark_set_sec_rec( /*=========================*/ ulint flags, /*!< in: locking flag */ btr_cur_t* cursor, /*!< in: cursor */ ibool val, /*!< in: value to set */ que_thr_t* thr, /*!< in: query thread */ mtr_t* mtr); /*!< in: mtr */ /***********************************************************//** Clear a secondary index record's delete mark. This function is only used by the insert buffer insert merge mechanism. */ UNIV_INTERN void btr_cur_del_unmark_for_ibuf( /*========================*/ rec_t* rec, /*!< in/out: record to delete unmark */ page_zip_des_t* page_zip, /*!< in/out: compressed page corresponding to rec, or NULL when the tablespace is uncompressed */ mtr_t* mtr); /*!< in: mtr */ /*************************************************************//** Tries to compress a page of the tree if it seems useful. It is assumed that mtr holds an x-latch on the tree and on the cursor page. To avoid deadlocks, mtr must also own x-latches to brothers of page, if those brothers exist. NOTE: it is assumed that the caller has reserved enough free extents so that the compression will always succeed if done! @return TRUE if compression occurred */ UNIV_INTERN ibool btr_cur_compress_if_useful( /*=======================*/ btr_cur_t* cursor, /*!< in: cursor on the page to compress; cursor does not stay valid if compression occurs */ mtr_t* mtr); /*!< in: mtr */ /*******************************************************//** Removes the record on which the tree cursor is positioned. It is assumed that the mtr has an x-latch on the page where the cursor is positioned, but no latch on the whole tree. @return TRUE if success, i.e., the page did not become too empty */ UNIV_INTERN ibool btr_cur_optimistic_delete( /*======================*/ btr_cur_t* cursor, /*!< in: cursor on the record to delete; cursor stays valid: if deletion succeeds, on function exit it points to the successor of the deleted record */ mtr_t* mtr); /*!< in: mtr; if this function returns TRUE on a leaf page of a secondary index, the mtr must be committed before latching any further pages */ /*************************************************************//** Removes the record on which the tree cursor is positioned. Tries to compress the page if its fillfactor drops below a threshold or if it is the only page on the level. It is assumed that mtr holds an x-latch on the tree and on the cursor page. To avoid deadlocks, mtr must also own x-latches to brothers of page, if those brothers exist. @return TRUE if compression occurred */ UNIV_INTERN ibool btr_cur_pessimistic_delete( /*=======================*/ ulint* err, /*!< out: DB_SUCCESS or DB_OUT_OF_FILE_SPACE; the latter may occur because we may have to update node pointers on upper levels, and in the case of variable length keys these may actually grow in size */ ibool has_reserved_extents, /*!< in: TRUE if the caller has already reserved enough free extents so that he knows that the operation will succeed */ btr_cur_t* cursor, /*!< in: cursor on the record to delete; if compression does not occur, the cursor stays valid: it points to successor of deleted record on function exit */ enum trx_rb_ctx rb_ctx, /*!< in: rollback context */ mtr_t* mtr); /*!< in: mtr */ #endif /* !UNIV_HOTBACKUP */ /***********************************************************//** Parses a redo log record of updating a record in-place. @return end of log record or NULL */ UNIV_INTERN byte* btr_cur_parse_update_in_place( /*==========================*/ byte* ptr, /*!< in: buffer */ byte* end_ptr,/*!< in: buffer end */ page_t* page, /*!< in/out: page or NULL */ page_zip_des_t* page_zip,/*!< in/out: compressed page, or NULL */ dict_index_t* index); /*!< in: index corresponding to page */ /****************************************************************//** Parses the redo log record for delete marking or unmarking of a clustered index record. @return end of log record or NULL */ UNIV_INTERN byte* btr_cur_parse_del_mark_set_clust_rec( /*=================================*/ byte* ptr, /*!< in: buffer */ byte* end_ptr,/*!< in: buffer end */ page_t* page, /*!< in/out: page or NULL */ page_zip_des_t* page_zip,/*!< in/out: compressed page, or NULL */ dict_index_t* index); /*!< in: index corresponding to page */ /****************************************************************//** Parses the redo log record for delete marking or unmarking of a secondary index record. @return end of log record or NULL */ UNIV_INTERN byte* btr_cur_parse_del_mark_set_sec_rec( /*===============================*/ byte* ptr, /*!< in: buffer */ byte* end_ptr,/*!< in: buffer end */ page_t* page, /*!< in/out: page or NULL */ page_zip_des_t* page_zip);/*!< in/out: compressed page, or NULL */ #ifndef UNIV_HOTBACKUP /*******************************************************************//** Estimates the number of rows in a given index range. @return estimated number of rows */ UNIV_INTERN ib_int64_t btr_estimate_n_rows_in_range( /*=========================*/ dict_index_t* index, /*!< in: index */ const dtuple_t* tuple1, /*!< in: range start, may also be empty tuple */ ulint mode1, /*!< in: search mode for range start */ const dtuple_t* tuple2, /*!< in: range end, may also be empty tuple */ ulint mode2); /*!< in: search mode for range end */ /*******************************************************************//** Estimates the number of different key values in a given index, for each n-column prefix of the index where n <= dict_index_get_n_unique(index). The estimates are stored in the array index->stat_n_diff_key_vals. */ UNIV_INTERN void btr_estimate_number_of_different_key_vals( /*======================================*/ dict_index_t* index); /*!< in: index */ /*******************************************************************//** Marks not updated extern fields as not-owned by this record. The ownership is transferred to the updated record which is inserted elsewhere in the index tree. In purge only the owner of externally stored field is allowed to free the field. */ UNIV_INTERN void btr_cur_mark_extern_inherited_fields( /*=================================*/ page_zip_des_t* page_zip,/*!< in/out: compressed page whose uncompressed part will be updated, or NULL */ rec_t* rec, /*!< in/out: record in a clustered index */ dict_index_t* index, /*!< in: index of the page */ const ulint* offsets,/*!< in: array returned by rec_get_offsets() */ const upd_t* update, /*!< in: update vector */ mtr_t* mtr); /*!< in: mtr, or NULL if not logged */ /*******************************************************************//** The complement of the previous function: in an update entry may inherit some externally stored fields from a record. We must mark them as inherited in entry, so that they are not freed in a rollback. */ UNIV_INTERN void btr_cur_mark_dtuple_inherited_extern( /*=================================*/ dtuple_t* entry, /*!< in/out: updated entry to be inserted to clustered index */ const upd_t* update); /*!< in: update vector */ /*******************************************************************//** Marks all extern fields in a dtuple as owned by the record. */ UNIV_INTERN void btr_cur_unmark_dtuple_extern_fields( /*================================*/ dtuple_t* entry); /*!< in/out: clustered index entry */ /*******************************************************************//** Stores the fields in big_rec_vec to the tablespace and puts pointers to them in rec. The extern flags in rec will have to be set beforehand. The fields are stored on pages allocated from leaf node file segment of the index tree. @return DB_SUCCESS or error */ UNIV_INTERN ulint btr_store_big_rec_extern_fields( /*============================*/ dict_index_t* index, /*!< in: index of rec; the index tree MUST be X-latched */ buf_block_t* rec_block, /*!< in/out: block containing rec */ rec_t* rec, /*!< in: record */ const ulint* offsets, /*!< in: rec_get_offsets(rec, index); the "external storage" flags in offsets will not correspond to rec when this function returns */ big_rec_t* big_rec_vec, /*!< in: vector containing fields to be stored externally */ mtr_t* local_mtr); /*!< in: mtr containing the latch to rec and to the tree */ /*******************************************************************//** Frees the space in an externally stored field to the file space management if the field in data is owned the externally stored field, in a rollback we may have the additional condition that the field must not be inherited. */ UNIV_INTERN void btr_free_externally_stored_field( /*=============================*/ dict_index_t* index, /*!< in: index of the data, the index tree MUST be X-latched; if the tree height is 1, then also the root page must be X-latched! (this is relevant in the case this function is called from purge where 'data' is located on an undo log page, not an index page) */ byte* field_ref, /*!< in/out: field reference */ const rec_t* rec, /*!< in: record containing field_ref, for page_zip_write_blob_ptr(), or NULL */ const ulint* offsets, /*!< in: rec_get_offsets(rec, index), or NULL */ page_zip_des_t* page_zip, /*!< in: compressed page corresponding to rec, or NULL if rec == NULL */ ulint i, /*!< in: field number of field_ref; ignored if rec == NULL */ enum trx_rb_ctx rb_ctx, /*!< in: rollback context */ mtr_t* local_mtr); /*!< in: mtr containing the latch to data an an X-latch to the index tree */ /*******************************************************************//** Copies the prefix of an externally stored field of a record. The clustered index record must be protected by a lock or a page latch. @return the length of the copied field, or 0 if the column was being or has been deleted */ UNIV_INTERN ulint btr_copy_externally_stored_field_prefix( /*====================================*/ byte* buf, /*!< out: the field, or a prefix of it */ ulint len, /*!< in: length of buf, in bytes */ ulint zip_size,/*!< in: nonzero=compressed BLOB page size, zero for uncompressed BLOBs */ const byte* data, /*!< in: 'internally' stored part of the field containing also the reference to the external part; must be protected by a lock or a page latch */ ulint local_len);/*!< in: length of data, in bytes */ /*******************************************************************//** Copies an externally stored field of a record to mem heap. @return the field copied to heap */ UNIV_INTERN byte* btr_rec_copy_externally_stored_field( /*=================================*/ const rec_t* rec, /*!< in: record in a clustered index; must be protected by a lock or a page latch */ const ulint* offsets,/*!< in: array returned by rec_get_offsets() */ ulint zip_size,/*!< in: nonzero=compressed BLOB page size, zero for uncompressed BLOBs */ ulint no, /*!< in: field number */ ulint* len, /*!< out: length of the field */ mem_heap_t* heap); /*!< in: mem heap */ /*******************************************************************//** Flags the data tuple fields that are marked as extern storage in the update vector. We use this function to remember which fields we must mark as extern storage in a record inserted for an update. @return number of flagged external columns */ UNIV_INTERN ulint btr_push_update_extern_fields( /*==========================*/ dtuple_t* tuple, /*!< in/out: data tuple */ const upd_t* update, /*!< in: update vector */ mem_heap_t* heap) /*!< in: memory heap */ __attribute__((nonnull)); /*######################################################################*/ /** In the pessimistic delete, if the page data size drops below this limit, merging it to a neighbor is tried */ #define BTR_CUR_PAGE_COMPRESS_LIMIT (UNIV_PAGE_SIZE / 2) /** A slot in the path array. We store here info on a search path down the tree. Each slot contains data on a single level of the tree. */ typedef struct btr_path_struct btr_path_t; struct btr_path_struct{ ulint nth_rec; /*!< index of the record where the page cursor stopped on this level (index in alphabetical order); value ULINT_UNDEFINED denotes array end */ ulint n_recs; /*!< number of records on the page */ }; #define BTR_PATH_ARRAY_N_SLOTS 250 /*!< size of path array (in slots) */ /** Values for the flag documenting the used search method */ enum btr_cur_method { BTR_CUR_HASH = 1, /*!< successful shortcut using the hash index */ BTR_CUR_HASH_FAIL, /*!< failure using hash, success using binary search: the misleading hash reference is stored in the field hash_node, and might be necessary to update */ BTR_CUR_BINARY, /*!< success using the binary search */ BTR_CUR_INSERT_TO_IBUF /*!< performed the intended insert to the insert buffer */ }; /** The tree cursor: the definition appears here only for the compiler to know struct size! */ struct btr_cur_struct { dict_index_t* index; /*!< index where positioned */ page_cur_t page_cur; /*!< page cursor */ buf_block_t* left_block; /*!< this field is used to store a pointer to the left neighbor page, in the cases BTR_SEARCH_PREV and BTR_MODIFY_PREV */ /*------------------------------*/ que_thr_t* thr; /*!< this field is only used when btr_cur_search_to_nth_level is called for an index entry insertion: the calling query thread is passed here to be used in the insert buffer */ /*------------------------------*/ /** The following fields are used in btr_cur_search_to_nth_level to pass information: */ /* @{ */ enum btr_cur_method flag; /*!< Search method used */ ulint tree_height; /*!< Tree height if the search is done for a pessimistic insert or update operation */ ulint up_match; /*!< If the search mode was PAGE_CUR_LE, the number of matched fields to the the first user record to the right of the cursor record after btr_cur_search_to_nth_level; for the mode PAGE_CUR_GE, the matched fields to the first user record AT THE CURSOR or to the right of it; NOTE that the up_match and low_match values may exceed the correct values for comparison to the adjacent user record if that record is on a different leaf page! (See the note in row_ins_duplicate_key.) */ ulint up_bytes; /*!< number of matched bytes to the right at the time cursor positioned; only used internally in searches: not defined after the search */ ulint low_match; /*!< if search mode was PAGE_CUR_LE, the number of matched fields to the first user record AT THE CURSOR or to the left of it after btr_cur_search_to_nth_level; NOT defined for PAGE_CUR_GE or any other search modes; see also the NOTE in up_match! */ ulint low_bytes; /*!< number of matched bytes to the right at the time cursor positioned; only used internally in searches: not defined after the search */ ulint n_fields; /*!< prefix length used in a hash search if hash_node != NULL */ ulint n_bytes; /*!< hash prefix bytes if hash_node != NULL */ ulint fold; /*!< fold value used in the search if flag is BTR_CUR_HASH */ /*------------------------------*/ /* @} */ btr_path_t* path_arr; /*!< in estimating the number of rows in range, we store in this array information of the path through the tree */ }; /** If pessimistic delete fails because of lack of file space, there is still a good change of success a little later. Try this many times. */ #define BTR_CUR_RETRY_DELETE_N_TIMES 100 /** If pessimistic delete fails because of lack of file space, there is still a good change of success a little later. Sleep this many microseconds between retries. */ #define BTR_CUR_RETRY_SLEEP_TIME 50000 /** The reference in a field for which data is stored on a different page. The reference is at the end of the 'locally' stored part of the field. 'Locally' means storage in the index record. We store locally a long enough prefix of each column so that we can determine the ordering parts of each index record without looking into the externally stored part. */ /*-------------------------------------- @{ */ #define BTR_EXTERN_SPACE_ID 0 /*!< space id where stored */ #define BTR_EXTERN_PAGE_NO 4 /*!< page no where stored */ #define BTR_EXTERN_OFFSET 8 /*!< offset of BLOB header on that page */ #define BTR_EXTERN_LEN 12 /*!< 8 bytes containing the length of the externally stored part of the BLOB. The 2 highest bits are reserved to the flags below. */ /*-------------------------------------- @} */ /* #define BTR_EXTERN_FIELD_REF_SIZE 20 // moved to btr0types.h */ /** The most significant bit of BTR_EXTERN_LEN (i.e., the most significant bit of the byte at smallest address) is set to 1 if this field does not 'own' the externally stored field; only the owner field is allowed to free the field in purge! */ #define BTR_EXTERN_OWNER_FLAG 128 /** If the second most significant bit of BTR_EXTERN_LEN (i.e., the second most significant bit of the byte at smallest address) is 1 then it means that the externally stored field was inherited from an earlier version of the row. In rollback we are not allowed to free an inherited external field. */ #define BTR_EXTERN_INHERITED_FLAG 64 /** Number of searches down the B-tree in btr_cur_search_to_nth_level(). */ extern ulint btr_cur_n_non_sea; /** Number of successful adaptive hash index lookups in btr_cur_search_to_nth_level(). */ extern ulint btr_cur_n_sea; /** Old value of btr_cur_n_non_sea. Copied by srv_refresh_innodb_monitor_stats(). Referenced by srv_printf_innodb_monitor(). */ extern ulint btr_cur_n_non_sea_old; /** Old value of btr_cur_n_sea. Copied by srv_refresh_innodb_monitor_stats(). Referenced by srv_printf_innodb_monitor(). */ extern ulint btr_cur_n_sea_old; #endif /* !UNIV_HOTBACKUP */ #ifndef UNIV_NONINL #include "btr0cur.ic" #endif #endif