????
Current Path : /usr/include/mysql/server/private/ |
Current File : //usr/include/mysql/server/private/sql_alter.h |
/* Copyright (c) 2010, 2014, Oracle and/or its affiliates. Copyright (c) 2013, 2021, 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 St, Fifth Floor, Boston, MA 02110-1335 USA */ #ifndef SQL_ALTER_TABLE_H #define SQL_ALTER_TABLE_H class Alter_drop; class Alter_column; class Alter_rename_key; class Alter_index_ignorability; class Key; /** Data describing the table being created by CREATE TABLE or altered by ALTER TABLE. */ class Alter_info { public: enum enum_enable_or_disable { LEAVE_AS_IS, ENABLE, DISABLE }; bool vers_prohibited(THD *thd) const; /** The different values of the ALGORITHM clause. Describes which algorithm to use when altering the table. */ enum enum_alter_table_algorithm { /* Use thd->variables.alter_algorithm for alter method. If this is also default then use the fastest possible ALTER TABLE method (INSTANT, NOCOPY, INPLACE, COPY) */ ALTER_TABLE_ALGORITHM_DEFAULT, // Copy if supported, error otherwise. ALTER_TABLE_ALGORITHM_COPY, // In-place if supported, error otherwise. ALTER_TABLE_ALGORITHM_INPLACE, // No Copy will refuse any operation which does rebuild. ALTER_TABLE_ALGORITHM_NOCOPY, // Instant should allow any operation that changes metadata only. ALTER_TABLE_ALGORITHM_INSTANT, // When there is no specification of algorithm during alter table. ALTER_TABLE_ALGORITHM_NONE }; /** The different values of the LOCK clause. Describes the level of concurrency during ALTER TABLE. */ enum enum_alter_table_lock { // Maximum supported level of concurency for the given operation. ALTER_TABLE_LOCK_DEFAULT, // Allow concurrent reads & writes. If not supported, give error. ALTER_TABLE_LOCK_NONE, // Allow concurrent reads only. If not supported, give error. ALTER_TABLE_LOCK_SHARED, // Block reads and writes. ALTER_TABLE_LOCK_EXCLUSIVE }; Lex_table_name db, table_name; // Columns and keys to be dropped. List<Alter_drop> drop_list; // Columns for ALTER_CHANGE_COLUMN_DEFAULT. List<Alter_column> alter_list; // List of keys, used by both CREATE and ALTER TABLE. List<Key> key_list; // List of keys to be renamed. List<Alter_rename_key> alter_rename_key_list; // List of columns, used by both CREATE and ALTER TABLE. List<Create_field> create_list; // Indexes whose ignorability needs to be changed. List<Alter_index_ignorability> alter_index_ignorability_list; List<Virtual_column_info> check_constraint_list; // Type of ALTER TABLE operation. alter_table_operations flags; ulong partition_flags; // Enable or disable keys. enum_enable_or_disable keys_onoff; // Used only in add_stat_drop_index() TABLE *original_table; // List of partitions. List<const char> partition_names; // Number of partitions. uint num_parts; /* List of fields that we should delete statistics from */ List<Field> drop_stat_fields; struct DROP_INDEX_STAT_PARAMS { KEY *key; bool ext_prefixes_only; }; struct RENAME_COLUMN_STAT_PARAMS { Field *field; LEX_CSTRING *name; uint duplicate_counter; // For temporary names }; struct RENAME_INDEX_STAT_PARAMS { const KEY *key; const LEX_CSTRING *name; uint duplicate_counter; // For temporary names uint usage_count; // How many rename entries }; /* List of index that we should delete statistics from */ List<DROP_INDEX_STAT_PARAMS> drop_stat_indexes; List<RENAME_COLUMN_STAT_PARAMS> rename_stat_fields; List<RENAME_INDEX_STAT_PARAMS> rename_stat_indexes; bool add_stat_drop_index(KEY *key, bool ext_prefixes_only, MEM_ROOT *mem_root) { DROP_INDEX_STAT_PARAMS *param; if (!(param= (DROP_INDEX_STAT_PARAMS*) alloc_root(mem_root, sizeof(*param)))) return true; param->key= key; param->ext_prefixes_only= ext_prefixes_only; return drop_stat_indexes.push_back(param, mem_root); } bool add_stat_drop_index(THD *thd, const LEX_CSTRING *key_name); bool add_stat_rename_index(const KEY *key, const LEX_CSTRING *name, MEM_ROOT *mem_root) { RENAME_INDEX_STAT_PARAMS *param; if (!(param= (RENAME_INDEX_STAT_PARAMS*) alloc_root(mem_root, sizeof(*param)))) return true; param->key= key; param->name= name; param->usage_count= 0; return rename_stat_indexes.push_back(param, mem_root); } bool add_stat_rename_field(Field *field, LEX_CSTRING *name, MEM_ROOT *mem_root) { RENAME_COLUMN_STAT_PARAMS *param; if (!(param= (RENAME_COLUMN_STAT_PARAMS*) alloc_root(mem_root, sizeof(*param)))) return true; param->field= field; param->name= name; param->duplicate_counter= 0; return rename_stat_fields.push_back(param, mem_root); } bool collect_renamed_fields(THD *thd); /* Delete/update statistics in EITS tables */ void apply_statistics_deletes_renames(THD *thd, TABLE *table); private: // Type of ALTER TABLE algorithm. enum_alter_table_algorithm requested_algorithm; public: // Type of ALTER TABLE lock. enum_alter_table_lock requested_lock; Alter_info() : flags(0), partition_flags(0), keys_onoff(LEAVE_AS_IS), original_table(0), num_parts(0), requested_algorithm(ALTER_TABLE_ALGORITHM_NONE), requested_lock(ALTER_TABLE_LOCK_DEFAULT) {} void reset() { drop_list.empty(); alter_list.empty(); key_list.empty(); alter_rename_key_list.empty(); create_list.empty(); alter_index_ignorability_list.empty(); check_constraint_list.empty(); drop_stat_fields.empty(); drop_stat_indexes.empty(); rename_stat_fields.empty(); rename_stat_indexes.empty(); flags= 0; partition_flags= 0; keys_onoff= LEAVE_AS_IS; num_parts= 0; partition_names.empty(); requested_algorithm= ALTER_TABLE_ALGORITHM_NONE; requested_lock= ALTER_TABLE_LOCK_DEFAULT; } /** Construct a copy of this object to be used for mysql_alter_table and mysql_create_table. Historically, these two functions modify their Alter_info arguments. This behaviour breaks re-execution of prepared statements and stored procedures and is compensated by always supplying a copy of Alter_info to these functions. @param rhs Alter_info to make copy of @param mem_root Mem_root for new Alter_info @note You need to use check the error in THD for out of memory condition after calling this function. */ Alter_info(const Alter_info &rhs, MEM_ROOT *mem_root); /** Parses the given string and sets requested_algorithm if the string value matches a supported value. Supported values: INPLACE, COPY, DEFAULT @param str String containing the supplied value @retval false Supported value found, state updated @retval true Not supported value, no changes made */ bool set_requested_algorithm(const LEX_CSTRING *str); /** Parses the given string and sets requested_lock if the string value matches a supported value. Supported values: NONE, SHARED, EXCLUSIVE, DEFAULT @param str String containing the supplied value @retval false Supported value found, state updated @retval true Not supported value, no changes made */ bool set_requested_lock(const LEX_CSTRING *str); /** Set the requested algorithm to the given algorithm value @param algo_value algorithm to be set */ void set_requested_algorithm(enum_alter_table_algorithm algo_value); /** Returns the algorithm value in the format "algorithm=value" */ const char* algorithm_clause(THD *thd) const; /** Returns the lock value in the format "lock=value" */ const char* lock() const; /** Check whether the given result can be supported with the specified user alter algorithm. @param thd Thread handle @param ha_alter_info Structure describing changes to be done by ALTER TABLE and holding data during in-place alter @retval false Supported operation @retval true Not supported value */ bool supports_algorithm(THD *thd, const Alter_inplace_info *ha_alter_info); /** Check whether the given result can be supported with the specified user lock type. @param ha_alter_info Structure describing changes to be done by ALTER TABLE and holding data during in-place alter @retval false Supported lock type @retval true Not supported value */ bool supports_lock(THD *thd, const Alter_inplace_info *ha_alter_info); /** Return user requested algorithm. If user does not specify algorithm then return alter_algorithm variable value. */ enum_alter_table_algorithm algorithm(const THD *thd) const; uint check_vcol_field(Item_field *f) const; private: Alter_info &operator=(const Alter_info &rhs); // not implemented Alter_info(const Alter_info &rhs); // not implemented }; /** Runtime context for ALTER TABLE. */ class Alter_table_ctx { public: Alter_table_ctx(); Alter_table_ctx(THD *thd, TABLE_LIST *table_list, uint tables_opened_arg, const LEX_CSTRING *new_db_arg, const LEX_CSTRING *new_name_arg); /** @return true if the table is moved to another database, false otherwise. */ bool is_database_changed() const { return (new_db.str != db.str); }; /** @return true if the table is renamed, false otherwise. */ bool is_table_renamed() const { return (is_database_changed() || new_name.str != table_name.str); }; /** @return filename (including .frm) for the new table. */ const char *get_new_filename() const { DBUG_ASSERT(!tmp_table); return new_filename; } /** @return path to the original table. */ const char *get_path() const { DBUG_ASSERT(!tmp_table); return path; } /** @return path to the new table. */ const char *get_new_path() const { DBUG_ASSERT(!tmp_table); return new_path; } /** @return path to the temporary table created during ALTER TABLE. */ const char *get_tmp_path() const { return tmp_path; } const LEX_CSTRING get_tmp_cstring_path() const { LEX_CSTRING tmp= { tmp_path, strlen(tmp_path) }; return tmp; }; /** Mark ALTER TABLE as needing to produce foreign key error if it deletes a row from the table being changed. */ void set_fk_error_if_delete_row(FOREIGN_KEY_INFO *fk) { fk_error_if_delete_row= true; fk_error_id= fk->foreign_id->str; fk_error_table= fk->foreign_table->str; } void report_implicit_default_value_error(THD *thd, const TABLE_SHARE *) const; public: Create_field *implicit_default_value_error_field= nullptr; bool error_if_not_empty= false; uint tables_opened= 0; LEX_CSTRING db; LEX_CSTRING table_name; LEX_CSTRING storage_engine_name; LEX_CSTRING alias; LEX_CSTRING new_db; LEX_CSTRING new_name; LEX_CSTRING new_alias; LEX_CSTRING tmp_name; LEX_CSTRING tmp_storage_engine_name; LEX_CUSTRING tmp_id, id; char tmp_buff[80]; uchar id_buff[MY_UUID_SIZE]; char storage_engine_buff[NAME_LEN], tmp_storage_engine_buff[NAME_LEN]; bool storage_engine_partitioned; bool tmp_storage_engine_name_partitioned; /** Indicates that if a row is deleted during copying of data from old version of table to the new version ER_FK_CANNOT_DELETE_PARENT error should be emitted. */ bool fk_error_if_delete_row= false; /** Name of foreign key for the above error. */ const char *fk_error_id= nullptr; /** Name of table for the above error. */ const char *fk_error_table= nullptr; bool modified_primary_key= false; /** Indicates that we are altering temporary table */ bool tmp_table= false; private: char new_filename[FN_REFLEN + 1]; char new_alias_buff[NAME_LEN + 1]; char tmp_name_buff[NAME_LEN + 1]; char path[FN_REFLEN + 1]; char new_path[FN_REFLEN + 1]; char tmp_path[FN_REFLEN + 1]; Alter_table_ctx &operator=(const Alter_table_ctx &rhs); // not implemented Alter_table_ctx(const Alter_table_ctx &rhs); // not implemented }; /** Sql_cmd_common_alter_table represents the common properties of the ALTER TABLE statements. @todo move Alter_info and other ALTER generic structures from Lex here. */ class Sql_cmd_common_alter_table : public Sql_cmd { protected: /** Constructor. */ Sql_cmd_common_alter_table() = default; virtual ~Sql_cmd_common_alter_table() = default; enum_sql_command sql_command_code() const override { return SQLCOM_ALTER_TABLE; } }; /** Sql_cmd_alter_table represents the generic ALTER TABLE statement. @todo move Alter_info and other ALTER specific structures from Lex here. */ class Sql_cmd_alter_table : public Sql_cmd_common_alter_table, public Storage_engine_name { public: /** Constructor, used to represent a ALTER TABLE statement. */ Sql_cmd_alter_table() = default; ~Sql_cmd_alter_table() = default; Storage_engine_name *option_storage_engine_name() override { return this; } bool execute(THD *thd) override; }; /** Sql_cmd_alter_sequence represents the ALTER SEQUENCE statement. */ class Sql_cmd_alter_sequence : public Sql_cmd, public DDL_options { public: /** Constructor, used to represent a ALTER TABLE statement. */ Sql_cmd_alter_sequence(const DDL_options &options) :DDL_options(options) {} ~Sql_cmd_alter_sequence() = default; enum_sql_command sql_command_code() const override { return SQLCOM_ALTER_SEQUENCE; } bool execute(THD *thd) override; }; /** Sql_cmd_alter_table_tablespace represents ALTER TABLE IMPORT/DISCARD TABLESPACE statements. */ class Sql_cmd_discard_import_tablespace : public Sql_cmd_common_alter_table { public: enum enum_tablespace_op_type { DISCARD_TABLESPACE, IMPORT_TABLESPACE }; Sql_cmd_discard_import_tablespace(enum_tablespace_op_type tablespace_op_arg) : m_tablespace_op(tablespace_op_arg) {} bool execute(THD *thd) override; private: const enum_tablespace_op_type m_tablespace_op; }; #endif