/***************************************************************************** Copyright (c) 1996, 2018, Oracle and/or its affiliates. All Rights Reserved. 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 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/row0upd.h Update of a row Created 12/27/1996 Heikki Tuuri *******************************************************/ #ifndef row0upd_h #define row0upd_h #include "data0data.h" #include "rem0types.h" #include "row0types.h" #include "btr0types.h" #include "trx0types.h" #include "btr0pcur.h" #include "que0types.h" #include "pars0types.h" /*********************************************************************//** Creates an update vector object. @return own: update vector object */ UNIV_INLINE upd_t* upd_create( /*=======*/ ulint n, /*!< in: number of fields */ mem_heap_t* heap); /*!< in: heap from which memory allocated */ /*********************************************************************//** Returns the number of fields in the update vector == number of columns to be updated by an update vector. @return number of fields */ UNIV_INLINE ulint upd_get_n_fields( /*=============*/ const upd_t* update); /*!< in: update vector */ #ifdef UNIV_DEBUG /*********************************************************************//** Returns the nth field of an update vector. @return update vector field */ UNIV_INLINE upd_field_t* upd_get_nth_field( /*==============*/ const upd_t* update, /*!< in: update vector */ ulint n); /*!< in: field position in update vector */ #else # define upd_get_nth_field(update, n) ((update)->fields + (n)) #endif /*********************************************************************//** Sets an index field number to be updated by an update vector field. */ UNIV_INLINE void upd_field_set_field_no( /*===================*/ upd_field_t* upd_field, /*!< in: update vector field */ uint16_t field_no, /*!< in: field number in a clustered index */ dict_index_t* index); /** set field number to a update vector field, marks this field is updated @param[in,out] upd_field update vector field @param[in] field_no virtual column sequence num @param[in] index index */ UNIV_INLINE void upd_field_set_v_field_no( upd_field_t* upd_field, uint16_t field_no, dict_index_t* index); /*********************************************************************//** Returns a field of an update vector by field_no. @return update vector field, or NULL */ UNIV_INLINE const upd_field_t* upd_get_field_by_field_no( /*======================*/ const upd_t* update, /*!< in: update vector */ uint16_t no, /*!< in: field_no */ bool is_virtual) /*!< in: if it is a virtual column */ MY_ATTRIBUTE((warn_unused_result)); /*********************************************************************//** Creates an update node for a query graph. @return own: update node */ upd_node_t* upd_node_create( /*============*/ mem_heap_t* heap); /*!< in: mem heap where created */ /***********************************************************//** Returns TRUE if row update changes size of some field in index or if some field to be updated is stored externally in rec or update. @return TRUE if the update changes the size of some field in index or the field is external in rec or update */ ibool row_upd_changes_field_size_or_external( /*===================================*/ dict_index_t* index, /*!< in: index */ const rec_offs* offsets,/*!< in: rec_get_offsets(rec, index) */ const upd_t* update);/*!< in: update vector */ /***************************************************************//** Builds an update vector from those fields which in a secondary index entry differ from a record that has the equal ordering fields. NOTE: we compare the fields as binary strings! @return own: update vector of differing fields */ upd_t* row_upd_build_sec_rec_difference_binary( /*====================================*/ const rec_t* rec, /*!< in: secondary index record */ dict_index_t* index, /*!< in: index */ const rec_offs* offsets,/*!< in: rec_get_offsets(rec, index) */ const dtuple_t* entry, /*!< in: entry to insert */ mem_heap_t* heap) /*!< in: memory heap from which allocated */ MY_ATTRIBUTE((warn_unused_result, nonnull)); /** Builds an update vector from those fields, excluding the roll ptr and trx id fields, which in an index entry differ from a record that has the equal ordering fields. NOTE: we compare the fields as binary strings! @param[in] index clustered index @param[in] entry clustered index entry to insert @param[in] rec clustered index record @param[in] offsets rec_get_offsets(rec,index), or NULL @param[in] no_sys skip the system columns DB_TRX_ID and DB_ROLL_PTR @param[in] ignore_warnings ignore warnings during vcol calculation, which means that this calculation is internal only @param[in] trx transaction (for diagnostics), or NULL @param[in] heap memory heap from which allocated @param[in,out] mysql_table NULL, or mysql table object when user thread invokes dml @param[out] error error number in case of failure @return own: update vector of differing fields, excluding roll ptr and trx id */ upd_t* row_upd_build_difference_binary( dict_index_t* index, const dtuple_t* entry, const rec_t* rec, const rec_offs* offsets, bool no_sys, bool ignore_warnings, trx_t* trx, mem_heap_t* heap, TABLE* mysql_table, dberr_t* error) MY_ATTRIBUTE((nonnull(1,2,3,8,10), warn_unused_result)); /** Apply an update vector to an index entry. @param[in,out] entry index entry to be updated; the clustered index record must be covered by a lock or a page latch to prevent deletion (rollback or purge) @param[in] index index of the entry @param[in] update update vector built for the entry @param[in,out] heap memory heap for copying off-page columns */ void row_upd_index_replace_new_col_vals_index_pos( dtuple_t* entry, const dict_index_t* index, const upd_t* update, mem_heap_t* heap) MY_ATTRIBUTE((nonnull)); /** Replace the new column values stored in the update vector, during trx_undo_prev_version_build(). @param entry clustered index tuple where the values are replaced (the clustered index leaf page latch must be held) @param index clustered index @param update update vector for the clustered index @param heap memory heap for allocating and copying values @return whether the previous version was built successfully */ bool row_upd_index_replace_new_col_vals(dtuple_t *entry, const dict_index_t &index, const upd_t *update, mem_heap_t *heap) MY_ATTRIBUTE((nonnull, warn_unused_result)); /***********************************************************//** Replaces the new column values stored in the update vector. */ void row_upd_replace( /*============*/ dtuple_t* row, /*!< in/out: row where replaced, indexed by col_no; the clustered index record must be covered by a lock or a page latch to prevent deletion (rollback or purge) */ row_ext_t** ext, /*!< out, own: NULL, or externally stored column prefixes */ const dict_index_t* index, /*!< in: clustered index */ const upd_t* update, /*!< in: an update vector built for the clustered index */ mem_heap_t* heap); /*!< in: memory heap */ /** Replaces the virtual column values stored in a dtuple with that of a update vector. @param[in,out] row dtuple whose column to be updated @param[in] table table @param[in] update an update vector built for the clustered index @param[in] upd_new update to new or old value @param[in,out] undo_row undo row (if needs to be updated) @param[in] ptr remaining part in update undo log */ void row_upd_replace_vcol( dtuple_t* row, const dict_table_t* table, const upd_t* update, bool upd_new, dtuple_t* undo_row, const byte* ptr); /***********************************************************//** Checks if an update vector changes an ordering field of an index record. This function is fast if the update vector is short or the number of ordering fields in the index is small. Otherwise, this can be quadratic. NOTE: we compare the fields as binary strings! @return TRUE if update vector changes an ordering field in the index record */ ibool row_upd_changes_ord_field_binary_func( /*==================================*/ dict_index_t* index, /*!< in: index of the record */ const upd_t* update, /*!< in: update vector for the row; NOTE: the field numbers in this MUST be clustered index positions! */ #ifdef UNIV_DEBUG const que_thr_t*thr, /*!< in: query thread */ #endif /* UNIV_DEBUG */ const dtuple_t* row, /*!< in: old value of row, or NULL if the row and the data values in update are not known when this function is called, e.g., at compile time */ const row_ext_t*ext, /*!< NULL, or prefixes of the externally stored columns in the old row */ ulint flag) /*!< in: ROW_BUILD_NORMAL, ROW_BUILD_FOR_PURGE or ROW_BUILD_FOR_UNDO */ MY_ATTRIBUTE((nonnull(1,2), warn_unused_result)); #ifdef UNIV_DEBUG # define row_upd_changes_ord_field_binary(index,update,thr,row,ext) \ row_upd_changes_ord_field_binary_func(index,update,thr,row,ext,0) #else /* UNIV_DEBUG */ # define row_upd_changes_ord_field_binary(index,update,thr,row,ext) \ row_upd_changes_ord_field_binary_func(index,update,row,ext,0) #endif /* UNIV_DEBUG */ /***********************************************************//** Checks if an FTS indexed column is affected by an UPDATE. @return offset within fts_t::indexes if FTS indexed column updated else ULINT_UNDEFINED */ ulint row_upd_changes_fts_column( /*=======================*/ dict_table_t* table, /*!< in: table */ upd_field_t* upd_field); /*!< in: field to check */ /***********************************************************//** Checks if an FTS Doc ID column is affected by an UPDATE. @return whether Doc ID column is affected */ bool row_upd_changes_doc_id( /*===================*/ dict_table_t* table, /*!< in: table */ upd_field_t* upd_field) /*!< in: field to check */ MY_ATTRIBUTE((nonnull, warn_unused_result)); /***********************************************************//** Checks if an update vector changes an ordering field of an index record. This function is fast if the update vector is short or the number of ordering fields in the index is small. Otherwise, this can be quadratic. NOTE: we compare the fields as binary strings! @return TRUE if update vector may change an ordering field in an index record */ ibool row_upd_changes_some_index_ord_field_binary( /*========================================*/ const dict_table_t* table, /*!< in: table */ const upd_t* update);/*!< in: update vector for the row */ /***********************************************************//** Updates a row in a table. This is a high-level function used in SQL execution graphs. @return query thread to run next or NULL */ que_thr_t* row_upd_step( /*=========*/ que_thr_t* thr); /*!< in: query thread */ /* Update vector field */ struct upd_field_t{ uint16_t field_no; /*!< field number in an index, usually the clustered index, but in updating a secondary index record in btr0cur.cc this is the position in the secondary index. If this field is a virtual column, then field_no represents the nth virtual column in the table */ uint16_t orig_len; /*!< original length of the locally stored part of an externally stored column, or 0 */ que_node_t* exp; /*!< expression for calculating a new value: it refers to column values and constants in the symbol table of the query graph */ dfield_t new_val; /*!< new value for the column */ dfield_t* old_v_val; /*!< old value for the virtual column */ }; /* check whether an update field is on virtual column */ #define upd_fld_is_virtual_col(upd_fld) \ (((upd_fld)->new_val.type.prtype & DATA_VIRTUAL) == DATA_VIRTUAL) /* set DATA_VIRTUAL bit on update field to show it is a virtual column */ #define upd_fld_set_virtual_col(upd_fld) \ ((upd_fld)->new_val.type.prtype |= DATA_VIRTUAL) /* Update vector structure */ struct upd_t{ mem_heap_t* heap; /*!< heap from which memory allocated */ byte info_bits; /*!< new value of info bits to record; default is 0 */ dtuple_t* old_vrow; /*!< pointer to old row, used for virtual column update now */ ulint n_fields; /*!< number of update fields */ upd_field_t* fields; /*!< array of update fields */ byte vers_sys_value[8]; /*!< buffer for updating system fields */ /** Append an update field to the end of array @param[in] field an update field */ void append(const upd_field_t& field) { fields[n_fields++] = field; } void remove_element(ulint i) { ut_ad(n_fields > 0); ut_ad(i < n_fields); while (i < n_fields - 1) { fields[i]= fields[i + 1]; i++; } n_fields--; } bool remove(const ulint field_no) { for (ulint i= 0; i < n_fields; ++i) { if (field_no == fields[i].field_no) { remove_element(i); return true; } } return false; } /** Determine if the given field_no is modified. @return true if modified, false otherwise. */ bool is_modified(uint16_t field_no) const { for (ulint i = 0; i < n_fields; ++i) { if (field_no == fields[i].field_no) { return(true); } } return(false); } /** Determine if the update affects a system versioned column or row_end. */ bool affects_versioned() const { for (ulint i = 0; i < n_fields; i++) { dtype_t type = fields[i].new_val.type; if (type.is_versioned()) { return true; } // versioned DELETE is UPDATE SET row_end=NOW if (type.vers_sys_end()) { return true; } } return false; } /** @return whether this is for a hidden metadata record for instant ALTER TABLE */ bool is_metadata() const { return dtuple_t::is_metadata(info_bits); } /** @return whether this is for a hidden metadata record for instant ALTER TABLE (not only ADD COLUMN) */ bool is_alter_metadata() const { return dtuple_t::is_alter_metadata(info_bits); } #ifdef UNIV_DEBUG bool validate() const { for (ulint i = 0; i < n_fields; ++i) { dfield_t* field = &fields[i].new_val; if (dfield_is_ext(field)) { ut_ad(dfield_get_len(field) >= BTR_EXTERN_FIELD_REF_SIZE); } } return(true); } #endif // UNIV_DEBUG }; /** Kinds of update operation */ enum delete_mode_t { NO_DELETE = 0, /*!< this operation does not delete */ PLAIN_DELETE, /*!< ordinary delete */ VERSIONED_DELETE /*!< update old and insert a new row */ }; /* Update node structure which also implements the delete operation of a row */ struct upd_node_t{ que_common_t common; /*!< node type: QUE_NODE_UPDATE */ delete_mode_t is_delete; /*!< kind of DELETE */ ibool searched_update; /* TRUE if searched update, FALSE if positioned */ bool in_mysql_interface; /* whether the update node was created for the MySQL interface */ dict_foreign_t* foreign;/* NULL or pointer to a foreign key constraint if this update node is used in doing an ON DELETE or ON UPDATE operation */ upd_node_t* cascade_node;/* NULL or an update node template which is used to implement ON DELETE/UPDATE CASCADE or ... SET NULL for foreign keys */ mem_heap_t* cascade_heap; /*!< NULL or a mem heap where cascade node is created.*/ sel_node_t* select; /*!< query graph subtree implementing a base table cursor: the rows returned will be updated */ btr_pcur_t* pcur; /*!< persistent cursor placed on the clustered index record which should be updated or deleted; the cursor is stored in the graph of 'select' field above, except in the case of the MySQL interface */ dict_table_t* table; /*!< table where updated */ upd_t* update; /*!< update vector for the row */ ulint update_n_fields; /* when this struct is used to implement a cascade operation for foreign keys, we store here the size of the buffer allocated for use as the update vector */ sym_node_list_t columns;/* symbol table nodes for the columns to retrieve from the table */ ibool has_clust_rec_x_lock; /* TRUE if the select which retrieves the records to update already sets an x-lock on the clustered record; note that it must always set at least an s-lock */ ulint cmpl_info;/* information extracted during query compilation; speeds up execution: UPD_NODE_NO_ORD_CHANGE and UPD_NODE_NO_SIZE_CHANGE, ORed */ /*----------------------*/ /* Local storage for this graph node */ ulint state; /*!< node execution state */ dict_index_t* index; /*!< NULL, or the next index whose record should be updated */ dtuple_t* row; /*!< NULL, or a copy (also fields copied to heap) of the row to update; this must be reset to NULL after a successful update */ dtuple_t* historical_row; /*!< historical row used in CASCADE UPDATE/SET NULL; allocated from historical_heap */ mem_heap_t* historical_heap; /*!< heap for historical row insertion; created when row to update is located; freed right before row update */ row_ext_t* ext; /*!< NULL, or prefixes of the externally stored columns in the old row */ dtuple_t* upd_row;/* NULL, or a copy of the updated row */ row_ext_t* upd_ext;/* NULL, or prefixes of the externally stored columns in upd_row */ mem_heap_t* heap; /*!< memory heap used as auxiliary storage; this must be emptied after a successful update */ /*----------------------*/ sym_node_t* table_sym;/* table node in symbol table */ que_node_t* col_assign_list; /* column assignment list */ ulint magic_n; private: /** Appends row_start or row_end field to update vector and sets a CURRENT_TIMESTAMP/trx->id value to it. Supposed to be called only by make_versioned_update() and make_versioned_delete(). @param[in] trx transaction @param[in] vers_sys_idx table->row_start or table->row_end */ void vers_update_fields(const trx_t *trx, ulint idx); public: /** Also set row_start = CURRENT_TIMESTAMP/trx->id @param[in] trx transaction */ void vers_make_update(const trx_t *trx) { vers_update_fields(trx, table->vers_start); } /** Prepare update vector for versioned delete. Set row_end to CURRENT_TIMESTAMP or trx->id. Initialize fts_next_doc_id for versioned delete. @param[in] trx transaction */ void vers_make_delete(trx_t *trx); }; #define UPD_NODE_MAGIC_N 1579975 /* Node execution states */ #define UPD_NODE_SET_IX_LOCK 1 /* execution came to the node from a node above and if the field has_clust_rec_x_lock is FALSE, we should set an intention x-lock on the table */ #define UPD_NODE_UPDATE_CLUSTERED 2 /* clustered index record should be updated */ #define UPD_NODE_INSERT_CLUSTERED 3 /* clustered index record should be inserted, old record is already delete marked */ #define UPD_NODE_UPDATE_ALL_SEC 5 /* an ordering field of the clustered index record was changed, or this is a delete operation: should update all the secondary index records */ #define UPD_NODE_UPDATE_SOME_SEC 6 /* secondary index entries should be looked at and updated if an ordering field changed */ /* Compilation info flags: these must fit within 3 bits; see trx0rec.h */ #define UPD_NODE_NO_ORD_CHANGE 1 /* no secondary index record will be changed in the update and no ordering field of the clustered index */ #define UPD_NODE_NO_SIZE_CHANGE 2 /* no record field size will be changed in the update */ #include "row0upd.inl" #endif