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Diffstat (limited to 'sql/sql_alter.cc')
| -rw-r--r-- | sql/sql_alter.cc | 583 |
1 files changed, 583 insertions, 0 deletions
diff --git a/sql/sql_alter.cc b/sql/sql_alter.cc new file mode 100644 index 00000000..7901c9b5 --- /dev/null +++ b/sql/sql_alter.cc @@ -0,0 +1,583 @@ +/* Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved. + Copyright (c) 2016, 2020, 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 */ + +#include "mariadb.h" +#include "sql_parse.h" // check_access +#include "sql_table.h" // mysql_alter_table, + // mysql_exchange_partition +#include "sql_alter.h" +#include "wsrep_mysqld.h" + +Alter_info::Alter_info(const Alter_info &rhs, MEM_ROOT *mem_root) + :drop_list(rhs.drop_list, mem_root), + alter_list(rhs.alter_list, mem_root), + key_list(rhs.key_list, mem_root), + alter_rename_key_list(rhs.alter_rename_key_list, mem_root), + create_list(rhs.create_list, mem_root), + check_constraint_list(rhs.check_constraint_list, mem_root), + flags(rhs.flags), partition_flags(rhs.partition_flags), + keys_onoff(rhs.keys_onoff), + partition_names(rhs.partition_names, mem_root), + num_parts(rhs.num_parts), + requested_algorithm(rhs.requested_algorithm), + requested_lock(rhs.requested_lock) +{ + /* + Make deep copies of used objects. + This is not a fully deep copy - clone() implementations + of Alter_drop, Alter_column, Key, foreign_key, Key_part_spec + do not copy string constants. At the same length the only + reason we make a copy currently is that ALTER/CREATE TABLE + code changes input Alter_info definitions, but string + constants never change. + */ + list_copy_and_replace_each_value(drop_list, mem_root); + list_copy_and_replace_each_value(alter_list, mem_root); + list_copy_and_replace_each_value(key_list, mem_root); + list_copy_and_replace_each_value(alter_rename_key_list, mem_root); + list_copy_and_replace_each_value(create_list, mem_root); + /* partition_names are not deeply copied currently */ +} + + +bool Alter_info::set_requested_algorithm(const LEX_CSTRING *str) +{ + // To avoid adding new keywords to the grammar, we match strings here. + if (lex_string_eq(str, STRING_WITH_LEN("INPLACE"))) + requested_algorithm= ALTER_TABLE_ALGORITHM_INPLACE; + else if (lex_string_eq(str, STRING_WITH_LEN("COPY"))) + requested_algorithm= ALTER_TABLE_ALGORITHM_COPY; + else if (lex_string_eq(str, STRING_WITH_LEN("DEFAULT"))) + requested_algorithm= ALTER_TABLE_ALGORITHM_DEFAULT; + else if (lex_string_eq(str, STRING_WITH_LEN("NOCOPY"))) + requested_algorithm= ALTER_TABLE_ALGORITHM_NOCOPY; + else if (lex_string_eq(str, STRING_WITH_LEN("INSTANT"))) + requested_algorithm= ALTER_TABLE_ALGORITHM_INSTANT; + else + return true; + return false; +} + +void Alter_info::set_requested_algorithm(enum_alter_table_algorithm algo_val) +{ + requested_algorithm= algo_val; +} + +bool Alter_info::set_requested_lock(const LEX_CSTRING *str) +{ + // To avoid adding new keywords to the grammar, we match strings here. + if (lex_string_eq(str, STRING_WITH_LEN("NONE"))) + requested_lock= ALTER_TABLE_LOCK_NONE; + else if (lex_string_eq(str, STRING_WITH_LEN("SHARED"))) + requested_lock= ALTER_TABLE_LOCK_SHARED; + else if (lex_string_eq(str, STRING_WITH_LEN("EXCLUSIVE"))) + requested_lock= ALTER_TABLE_LOCK_EXCLUSIVE; + else if (lex_string_eq(str, STRING_WITH_LEN("DEFAULT"))) + requested_lock= ALTER_TABLE_LOCK_DEFAULT; + else + return true; + return false; +} + +const char* Alter_info::algorithm_clause(THD *thd) const +{ + switch (algorithm(thd)) { + case ALTER_TABLE_ALGORITHM_INPLACE: + return "ALGORITHM=INPLACE"; + case ALTER_TABLE_ALGORITHM_COPY: + return "ALGORITHM=COPY"; + case ALTER_TABLE_ALGORITHM_NONE: + DBUG_ASSERT(0); + /* Fall through */ + case ALTER_TABLE_ALGORITHM_DEFAULT: + return "ALGORITHM=DEFAULT"; + case ALTER_TABLE_ALGORITHM_NOCOPY: + return "ALGORITHM=NOCOPY"; + case ALTER_TABLE_ALGORITHM_INSTANT: + return "ALGORITHM=INSTANT"; + } + + return NULL; /* purecov: begin deadcode */ +} + +const char* Alter_info::lock() const +{ + switch (requested_lock) { + case ALTER_TABLE_LOCK_SHARED: + return "LOCK=SHARED"; + case ALTER_TABLE_LOCK_NONE: + return "LOCK=NONE"; + case ALTER_TABLE_LOCK_DEFAULT: + return "LOCK=DEFAULT"; + case ALTER_TABLE_LOCK_EXCLUSIVE: + return "LOCK=EXCLUSIVE"; + } + return NULL; /* purecov: begin deadcode */ +} + + +bool Alter_info::supports_algorithm(THD *thd, + const Alter_inplace_info *ha_alter_info) +{ + switch (ha_alter_info->inplace_supported) { + case HA_ALTER_INPLACE_EXCLUSIVE_LOCK: + case HA_ALTER_INPLACE_SHARED_LOCK: + case HA_ALTER_INPLACE_NO_LOCK: + case HA_ALTER_INPLACE_INSTANT: + return false; + case HA_ALTER_INPLACE_COPY_NO_LOCK: + case HA_ALTER_INPLACE_COPY_LOCK: + if (algorithm(thd) >= Alter_info::ALTER_TABLE_ALGORITHM_NOCOPY) + { + ha_alter_info->report_unsupported_error(algorithm_clause(thd), + "ALGORITHM=INPLACE"); + return true; + } + return false; + case HA_ALTER_INPLACE_NOCOPY_NO_LOCK: + case HA_ALTER_INPLACE_NOCOPY_LOCK: + if (algorithm(thd) == Alter_info::ALTER_TABLE_ALGORITHM_INSTANT) + { + ha_alter_info->report_unsupported_error("ALGORITHM=INSTANT", + "ALGORITHM=NOCOPY"); + return true; + } + return false; + case HA_ALTER_INPLACE_NOT_SUPPORTED: + if (algorithm(thd) >= Alter_info::ALTER_TABLE_ALGORITHM_INPLACE) + { + ha_alter_info->report_unsupported_error(algorithm_clause(thd), + "ALGORITHM=COPY"); + return true; + } + return false; + case HA_ALTER_ERROR: + return true; + } + /* purecov: begin deadcode */ + DBUG_ASSERT(0); + return false; +} + + +bool Alter_info::supports_lock(THD *thd, + const Alter_inplace_info *ha_alter_info) +{ + switch (ha_alter_info->inplace_supported) { + case HA_ALTER_INPLACE_EXCLUSIVE_LOCK: + // If SHARED lock and no particular algorithm was requested, use COPY. + if (requested_lock == Alter_info::ALTER_TABLE_LOCK_SHARED && + algorithm(thd) == Alter_info::ALTER_TABLE_ALGORITHM_DEFAULT && + thd->variables.alter_algorithm == + Alter_info::ALTER_TABLE_ALGORITHM_DEFAULT) + return false; + + if (requested_lock == Alter_info::ALTER_TABLE_LOCK_SHARED || + requested_lock == Alter_info::ALTER_TABLE_LOCK_NONE) + { + ha_alter_info->report_unsupported_error(lock(), "LOCK=EXCLUSIVE"); + return true; + } + return false; + case HA_ALTER_INPLACE_NO_LOCK: + case HA_ALTER_INPLACE_INSTANT: + case HA_ALTER_INPLACE_COPY_NO_LOCK: + case HA_ALTER_INPLACE_NOCOPY_NO_LOCK: + return false; + case HA_ALTER_INPLACE_COPY_LOCK: + case HA_ALTER_INPLACE_NOCOPY_LOCK: + case HA_ALTER_INPLACE_NOT_SUPPORTED: + case HA_ALTER_INPLACE_SHARED_LOCK: + if (requested_lock == Alter_info::ALTER_TABLE_LOCK_NONE) + { + ha_alter_info->report_unsupported_error("LOCK=NONE", "LOCK=SHARED"); + return true; + } + return false; + case HA_ALTER_ERROR: + return true; + } + /* purecov: begin deadcode */ + DBUG_ASSERT(0); + return false; +} + +bool Alter_info::vers_prohibited(THD *thd) const +{ + if (thd->slave_thread || + thd->variables.vers_alter_history != VERS_ALTER_HISTORY_ERROR) + { + return false; + } + if (flags & ( + ALTER_PARSER_ADD_COLUMN | + ALTER_PARSER_DROP_COLUMN | + ALTER_CHANGE_COLUMN | + ALTER_COLUMN_ORDER)) + { + return true; + } + if (flags & ALTER_ADD_INDEX) + { + List_iterator_fast<Key> key_it(const_cast<List<Key> &>(key_list)); + Key *key; + while ((key= key_it++)) + { + if (key->type == Key::PRIMARY || key->type == Key::UNIQUE) + return true; + } + } + return false; +} + +Alter_info::enum_alter_table_algorithm +Alter_info::algorithm(const THD *thd) const +{ + if (requested_algorithm == ALTER_TABLE_ALGORITHM_NONE) + return (Alter_info::enum_alter_table_algorithm) thd->variables.alter_algorithm; + return requested_algorithm; +} + + +Alter_table_ctx::Alter_table_ctx() + : implicit_default_value_error_field(NULL), + error_if_not_empty(false), + tables_opened(0), + db(null_clex_str), table_name(null_clex_str), alias(null_clex_str), + new_db(null_clex_str), new_name(null_clex_str), new_alias(null_clex_str), + fk_error_if_delete_row(false), fk_error_id(NULL), + fk_error_table(NULL) +#ifdef DBUG_ASSERT_EXISTS + , tmp_table(false) +#endif +{ +} + +/* + TODO: new_name_arg changes if lower case table names. + Should be copied or converted before call +*/ + +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) + : implicit_default_value_error_field(NULL), error_if_not_empty(false), + tables_opened(tables_opened_arg), + new_db(*new_db_arg), new_name(*new_name_arg), + fk_error_if_delete_row(false), fk_error_id(NULL), + fk_error_table(NULL) +#ifdef DBUG_ASSERT_EXISTS + , tmp_table(false) +#endif +{ + /* + Assign members db, table_name, new_db and new_name + to simplify further comparisions: we want to see if it's a RENAME + later just by comparing the pointers, avoiding the need for strcmp. + */ + db= table_list->db; + table_name= table_list->table_name; + alias= (lower_case_table_names == 2) ? table_list->alias : table_name; + + if (!new_db.str || !my_strcasecmp(table_alias_charset, new_db.str, db.str)) + new_db= db; + + if (new_name.str) + { + DBUG_PRINT("info", ("new_db.new_name: '%s'.'%s'", new_db.str, new_name.str)); + + if (lower_case_table_names == 1) // Convert new_name/new_alias to lower + { + new_name.length= my_casedn_str(files_charset_info, (char*) new_name.str); + new_alias= new_name; + } + else if (lower_case_table_names == 2) // Convert new_name to lower case + { + new_alias.str= new_alias_buff; + new_alias.length= new_name.length; + strmov(new_alias_buff, new_name.str); + new_name.length= my_casedn_str(files_charset_info, (char*) new_name.str); + + } + else + new_alias= new_name; // LCTN=0 => case sensitive + case preserving + + if (!is_database_changed() && + !my_strcasecmp(table_alias_charset, new_name.str, table_name.str)) + { + /* + Source and destination table names are equal: + make is_table_renamed() more efficient. + */ + new_alias= table_name; + new_name= table_name; + } + } + else + { + new_alias= alias; + new_name= table_name; + } + + tmp_name.str= tmp_name_buff; + tmp_name.length= my_snprintf(tmp_name_buff, sizeof(tmp_name_buff), + "%s-alter-%lx-%llx", + tmp_file_prefix, current_pid, thd->thread_id); + /* Safety fix for InnoDB */ + if (lower_case_table_names) + tmp_name.length= my_casedn_str(files_charset_info, tmp_name_buff); + + if (table_list->table->s->tmp_table == NO_TMP_TABLE) + { + build_table_filename(path, sizeof(path) - 1, db.str, table_name.str, "", 0); + + build_table_filename(new_path, sizeof(new_path) - 1, new_db.str, new_name.str, "", 0); + + build_table_filename(new_filename, sizeof(new_filename) - 1, + new_db.str, new_name.str, reg_ext, 0); + + build_table_filename(tmp_path, sizeof(tmp_path) - 1, new_db.str, tmp_name.str, "", + FN_IS_TMP); + } + else + { + /* + We are not filling path, new_path and new_filename members if + we are altering temporary table as these members are not used in + this case. This fact is enforced with assert. + */ + build_tmptable_filename(thd, tmp_path, sizeof(tmp_path)); +#ifdef DBUG_ASSERT_EXISTS + tmp_table= true; +#endif + } +} + + +void Alter_table_ctx::report_implicit_default_value_error(THD *thd, + const TABLE_SHARE *s) + const +{ + Create_field *error_field= implicit_default_value_error_field; + const Type_handler *h= error_field->type_handler(); + thd->push_warning_truncated_value_for_field(Sql_condition::WARN_LEVEL_WARN, + h->name().ptr(), + h->default_value().ptr(), + s ? s->db.str : nullptr, + s ? s->table_name.str : nullptr, + error_field->field_name.str); +} + + +bool Sql_cmd_alter_table::execute(THD *thd) +{ + LEX *lex= thd->lex; + /* first SELECT_LEX (have special meaning for many of non-SELECTcommands) */ + SELECT_LEX *select_lex= lex->first_select_lex(); + /* first table of first SELECT_LEX */ + TABLE_LIST *first_table= (TABLE_LIST*) select_lex->table_list.first; + + const bool used_engine= lex->create_info.used_fields & HA_CREATE_USED_ENGINE; + DBUG_ASSERT((m_storage_engine_name.str != NULL) == used_engine); + if (used_engine) + { + if (resolve_storage_engine_with_error(thd, &lex->create_info.db_type, + lex->create_info.tmp_table())) + return true; // Engine not found, substitution is not allowed + if (!lex->create_info.db_type) // Not found, but substitution is allowed + lex->create_info.used_fields&= ~HA_CREATE_USED_ENGINE; + } + + /* + Code in mysql_alter_table() may modify its HA_CREATE_INFO argument, + so we have to use a copy of this structure to make execution + prepared statement- safe. A shallow copy is enough as no memory + referenced from this structure will be modified. + @todo move these into constructor... + */ + HA_CREATE_INFO create_info(lex->create_info); + Alter_info alter_info(lex->alter_info, thd->mem_root); + create_info.alter_info= &alter_info; + privilege_t priv(NO_ACL); + privilege_t priv_needed(ALTER_ACL); + bool result; + + DBUG_ENTER("Sql_cmd_alter_table::execute"); + + if (unlikely(thd->is_fatal_error)) + { + /* out of memory creating a copy of alter_info */ + DBUG_RETURN(TRUE); + } + /* + We also require DROP priv for ALTER TABLE ... DROP PARTITION, as well + as for RENAME TO, as being done by SQLCOM_RENAME_TABLE + */ + if ((alter_info.partition_flags & ALTER_PARTITION_DROP) || + (alter_info.flags & ALTER_RENAME)) + priv_needed|= DROP_ACL; + + /* Must be set in the parser */ + DBUG_ASSERT(select_lex->db.str); + DBUG_ASSERT(!(alter_info.partition_flags & ALTER_PARTITION_EXCHANGE)); + DBUG_ASSERT(!(alter_info.partition_flags & ALTER_PARTITION_ADMIN)); + if (check_access(thd, priv_needed, first_table->db.str, + &first_table->grant.privilege, + &first_table->grant.m_internal, + 0, 0) || + check_access(thd, INSERT_ACL | CREATE_ACL, select_lex->db.str, + &priv, + NULL, /* Don't use first_tab->grant with sel_lex->db */ + 0, 0)) + DBUG_RETURN(TRUE); /* purecov: inspected */ + + /* If it is a merge table, check privileges for merge children. */ + if (create_info.merge_list) + { + /* + The user must have (SELECT_ACL | UPDATE_ACL | DELETE_ACL) on the + underlying base tables, even if there are temporary tables with the same + names. + + From user's point of view, it might look as if the user must have these + privileges on temporary tables to create a merge table over them. This is + one of two cases when a set of privileges is required for operations on + temporary tables (see also CREATE TABLE). + + The reason for this behavior stems from the following facts: + + - For merge tables, the underlying table privileges are checked only + at CREATE TABLE / ALTER TABLE time. + + In other words, once a merge table is created, the privileges of + the underlying tables can be revoked, but the user will still have + access to the merge table (provided that the user has privileges on + the merge table itself). + + - Temporary tables shadow base tables. + + I.e. there might be temporary and base tables with the same name, and + the temporary table takes the precedence in all operations. + + - For temporary MERGE tables we do not track if their child tables are + base or temporary. As result we can't guarantee that privilege check + which was done in presence of temporary child will stay relevant + later as this temporary table might be removed. + + If SELECT_ACL | UPDATE_ACL | DELETE_ACL privileges were not checked for + the underlying *base* tables, it would create a security breach as in + Bug#12771903. + */ + + if (check_table_access(thd, SELECT_ACL | UPDATE_ACL | DELETE_ACL, + create_info.merge_list, FALSE, UINT_MAX, FALSE)) + DBUG_RETURN(TRUE); + } + + if (check_grant(thd, priv_needed, first_table, FALSE, UINT_MAX, FALSE)) + DBUG_RETURN(TRUE); /* purecov: inspected */ +#ifdef WITH_WSREP + if (WSREP(thd) && + (!thd->is_current_stmt_binlog_format_row() || + !thd->find_temporary_table(first_table))) + { + wsrep::key_array keys; + wsrep_append_fk_parent_table(thd, first_table, &keys); + + WSREP_TO_ISOLATION_BEGIN_ALTER(lex->name.str ? select_lex->db.str + : first_table->db.str, + lex->name.str ? lex->name.str + : first_table->table_name.str, + first_table, &alter_info, &keys, + used_engine ? &create_info : nullptr); + + thd->variables.auto_increment_offset = 1; + thd->variables.auto_increment_increment = 1; + } +#endif + + if (lex->name.str && !test_all_bits(priv, INSERT_ACL | CREATE_ACL)) + { + // Rename of table + TABLE_LIST tmp_table; + tmp_table.init_one_table(&select_lex->db, &lex->name, 0, TL_IGNORE); + tmp_table.grant.privilege= priv; + if (check_grant(thd, INSERT_ACL | CREATE_ACL, &tmp_table, FALSE, + UINT_MAX, FALSE)) + DBUG_RETURN(TRUE); /* purecov: inspected */ + } + + /* Don't yet allow changing of symlinks with ALTER TABLE */ + if (create_info.data_file_name) + push_warning_printf(thd, Sql_condition::WARN_LEVEL_WARN, + WARN_OPTION_IGNORED, ER_THD(thd, WARN_OPTION_IGNORED), + "DATA DIRECTORY"); + if (create_info.index_file_name) + push_warning_printf(thd, Sql_condition::WARN_LEVEL_WARN, + WARN_OPTION_IGNORED, ER_THD(thd, WARN_OPTION_IGNORED), + "INDEX DIRECTORY"); + create_info.data_file_name= create_info.index_file_name= NULL; + +#ifdef WITH_PARTITION_STORAGE_ENGINE + thd->work_part_info= 0; +#endif + + result= mysql_alter_table(thd, &select_lex->db, &lex->name, + &create_info, + first_table, + &alter_info, + select_lex->order_list.elements, + select_lex->order_list.first, + lex->ignore, lex->if_exists()); + + DBUG_RETURN(result); +#ifdef WITH_WSREP +wsrep_error_label: + WSREP_WARN("ALTER TABLE isolation failure"); + DBUG_RETURN(TRUE); +#endif +} + +bool Sql_cmd_discard_import_tablespace::execute(THD *thd) +{ + /* first SELECT_LEX (have special meaning for many of non-SELECTcommands) */ + SELECT_LEX *select_lex= thd->lex->first_select_lex(); + /* first table of first SELECT_LEX */ + TABLE_LIST *table_list= (TABLE_LIST*) select_lex->table_list.first; + + if (check_access(thd, ALTER_ACL, table_list->db.str, + &table_list->grant.privilege, + &table_list->grant.m_internal, + 0, 0)) + return true; + + if (check_grant(thd, ALTER_ACL, table_list, false, UINT_MAX, false)) + return true; + + /* + Check if we attempt to alter mysql.slow_log or + mysql.general_log table and return an error if + it is the case. + TODO: this design is obsolete and will be removed. + */ + if (check_if_log_table(table_list, TRUE, "ALTER")) + return true; + + return + mysql_discard_or_import_tablespace(thd, table_list, + m_tablespace_op == DISCARD_TABLESPACE); +} |