diff options
Diffstat (limited to 'storage/innobase/include/trx0undo.h')
| -rw-r--r-- | storage/innobase/include/trx0undo.h | 101 |
1 files changed, 100 insertions, 1 deletions
diff --git a/storage/innobase/include/trx0undo.h b/storage/innobase/include/trx0undo.h index 62662ffe221..111369e6a0f 100644 --- a/storage/innobase/include/trx0undo.h +++ b/storage/innobase/include/trx0undo.h @@ -1,7 +1,7 @@ /***************************************************************************** Copyright (c) 1996, 2016, Oracle and/or its affiliates. All Rights Reserved. -Copyright (c) 2017, 2021, MariaDB Corporation. +Copyright (c) 2017, 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 @@ -326,6 +326,105 @@ struct trx_undo_t { /*!< undo log objects in the rollback segment are chained into lists */ }; + +/** Cache a pointer to an undo record in a latched buffer pool page, +parse the undo log record and store the record type, update vector +and compiler information */ +class UndorecApplier +{ + /** undo log block which was latched */ + const buf_block_t *block; + /** Undo log record pointer */ + trx_undo_rec_t *undo_rec; + /** Offset of the undo log record within the block */ + ulint offset; + /** Transaction id of the undo log */ + trx_id_t trx_id; + /** Undo log record type */ + ulint type; + /** compiler information */ + ulint cmpl_info; + /** Update vector */ + upd_t *update; + /** memory heap which can be used to build previous version of + the index record and its offsets */ + mem_heap_t *heap; + /** mini-transaction for accessing B-tree pages */ + mtr_t mtr; + +public: + UndorecApplier(const buf_block_t *block, trx_id_t trx_id) + : block(block), trx_id(trx_id) + { + ut_ad(block->page.lock.have_any()); + heap= mem_heap_create(100); + } + + /** Assign the undo log block */ + void assign_block(const buf_block_t *undo_block) + { + block= undo_block; + } + + /** Assign the undo log record and offset */ + void assign_rec(trx_undo_rec_t *rec); + + /** Handle the DML undo log and apply it on online indexes */ + void apply_undo_rec(); + + ~UndorecApplier() + { + mem_heap_free(heap); + } + +private: + /** Handle the insert undo log and apply it on online indexes + @param tuple row reference from undo log record + @param clust_index clustered index */ + void log_insert(const dtuple_t &tuple, dict_index_t *clust_index); + + /** Handle the update, delete undo log and apply it on online + indexes. + @param tuple row reference from undo log record + @param clust_index clustered index */ + void log_update(const dtuple_t &tuple, dict_index_t *clust_index); + + /** Check whether the given roll pointer is generated by + the current undo log record information stored. + @return true if roll pointer matches with current undo log info */ + bool is_same(roll_ptr_t roll_ptr) const + { + uint16_t offset= static_cast<uint16_t>(roll_ptr); + uint32_t page_no= static_cast<uint32_t>(roll_ptr >> 16); + return page_no == block->page.id().page_no() && offset == this->offset; + } + + /** Clear the undo log record information */ + void clear_undo_rec() + { + undo_rec= nullptr; + cmpl_info= 0; + type= 0; + update= nullptr; + offset= 0; + mem_heap_empty(heap); + } + + /** Get the correct version of the clustered index record that + was modified by the current undo log record. Because there could + be the multiple successive updates of the same record within the + same transaction. + @param tuple tuple contains primary key value + @param index clustered index + @param[out] clust_rec current clustered index record + @param offsets offsets points to the record + @return clustered index record which was changed by + the undo log record or nullptr when there is no clustered + index record changed by undo log record */ + const rec_t* get_old_rec(const dtuple_t &tuple, dict_index_t *index, + const rec_t **clust_rec, rec_offs **offsets); +}; + #endif /* !UNIV_INNOCHECKSUM */ /** The offset of the undo log page header on pages of the undo log */ |