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Diffstat (limited to 'storage/innobase/include/btr0cur.inl')
| -rw-r--r-- | storage/innobase/include/btr0cur.inl | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/storage/innobase/include/btr0cur.inl b/storage/innobase/include/btr0cur.inl new file mode 100644 index 00000000..955cf342 --- /dev/null +++ b/storage/innobase/include/btr0cur.inl @@ -0,0 +1,170 @@ +/***************************************************************************** + +Copyright (c) 1994, 2015, Oracle and/or its affiliates. All Rights Reserved. +Copyright (c) 2018, 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 include/btr0cur.ic +The index tree cursor + +Created 10/16/1994 Heikki Tuuri +*******************************************************/ + +#include "btr0btr.h" + +#ifdef UNIV_DEBUG +# define LIMIT_OPTIMISTIC_INSERT_DEBUG(NREC, CODE)\ +if (btr_cur_limit_optimistic_insert_debug > 1\ + && (NREC) >= btr_cur_limit_optimistic_insert_debug) {\ + CODE;\ +} +#else +# define LIMIT_OPTIMISTIC_INSERT_DEBUG(NREC, CODE) +#endif /* UNIV_DEBUG */ + +/*********************************************************//** +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 */ +{ + return(buf_block_get_page_zip(btr_cur_get_block(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 */ +{ + return(page_align(page_cur_get_rec(&(cursor->page_cur)))); +} + +/*********************************************************//** +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) /*!< out: cursor */ +{ + page_cur_position(rec, block, btr_cur_get_page_cur(cursor)); + cursor->page_cur.index = index; +} + +/*********************************************************************//** +Checks if compressing an index page where a btr cursor is placed makes +sense. +@return TRUE if compression is recommended */ +UNIV_INLINE +ibool +btr_cur_compress_recommendation( +/*============================*/ + btr_cur_t* cursor, /*!< in: btr cursor */ + mtr_t* mtr) /*!< in: mtr */ +{ + const page_t* page; + + ut_ad(mtr->memo_contains_flagged(btr_cur_get_block(cursor), + MTR_MEMO_PAGE_X_FIX)); + + page = btr_cur_get_page(cursor); + + LIMIT_OPTIMISTIC_INSERT_DEBUG(page_get_n_recs(page) * 2U, + return(FALSE)); + + if (!page_has_siblings(page) + || page_get_data_size(page) + < BTR_CUR_PAGE_COMPRESS_LIMIT(cursor->index())) { + + /* The page fillfactor has dropped below a predefined + minimum value OR the level in the B-tree contains just + one page: we recommend compression if this is not the + root page. */ + + return cursor->index()->page + != btr_cur_get_block(cursor)->page.id().page_no(); + } + + return(FALSE); +} + +/*********************************************************************//** +Checks if the record on which the cursor is placed can be deleted without +making tree compression necessary (or, recommended). +@return TRUE if can be deleted without recommended compression */ +UNIV_INLINE +ibool +btr_cur_can_delete_without_compress( +/*================================*/ + btr_cur_t* cursor, /*!< in: btr cursor */ + ulint rec_size,/*!< in: rec_get_size(btr_cur_get_rec(cursor))*/ + mtr_t* mtr) /*!< in: mtr */ +{ + page_t* page; + + ut_ad(mtr->memo_contains_flagged(btr_cur_get_block(cursor), + MTR_MEMO_PAGE_X_FIX)); + + page = btr_cur_get_page(cursor); + + if (!page_has_siblings(page) || page_get_n_recs(page) < 2 + || page_get_data_size(page) - rec_size + < BTR_CUR_PAGE_COMPRESS_LIMIT(cursor->index())) { + + /* The page fillfactor will drop below a predefined + minimum value, OR the level in the B-tree contains just + one page, OR the page will become empty: we recommend + compression if this is not the root page. */ + + return cursor->index()->page + == btr_cur_get_block(cursor)->page.id().page_no(); + } + + return(TRUE); +} + +/*******************************************************************//** +Determine if an operation on off-page columns is an update. +@return TRUE if op != BTR_STORE_INSERT */ +UNIV_INLINE +ibool +btr_blob_op_is_update( +/*==================*/ + enum blob_op op) /*!< in: operation */ +{ + switch (op) { + case BTR_STORE_INSERT: + case BTR_STORE_INSERT_BULK: + return(FALSE); + case BTR_STORE_INSERT_UPDATE: + case BTR_STORE_UPDATE: + return(TRUE); + } + + ut_ad(0); + return(FALSE); +} |