/* Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License, version 2.0, as published by the Free Software Foundation. This program is also distributed with certain software (including but not limited to OpenSSL) that is licensed under separate terms, as designated in a particular file or component or in included license documentation. The authors of MySQL hereby grant you an additional permission to link the program and your derivative works with the separately licensed software that they have included with MySQL. 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, version 2.0, 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 02110-1301 USA */ #define MYSQL_SERVER 1 #include "storage/heap/ha_heap.h" #include #include #include "my_dbug.h" #include "my_macros.h" #include "my_pointer_arithmetic.h" #include "my_psi_config.h" #include "mysql/plugin.h" #include "sql/current_thd.h" #include "sql/field.h" #include "sql/sql_base.h" // enum_tdc_remove_table_type #include "sql/sql_class.h" #include "sql/sql_plugin.h" #include "storage/heap/heapdef.h" static handler *heap_create_handler(handlerton *hton, TABLE_SHARE *table, bool partitioned, MEM_ROOT *mem_root); static int heap_prepare_hp_create_info(TABLE *table_arg, bool single_instance, bool delete_on_close, HP_CREATE_INFO *hp_create_info); static int heap_panic(handlerton *, ha_panic_function flag) { return hp_panic(flag); } static int heap_init(void *p) { handlerton *heap_hton; #ifdef HAVE_PSI_INTERFACE init_heap_psi_keys(); #endif heap_hton = (handlerton *)p; heap_hton->state = SHOW_OPTION_YES; heap_hton->db_type = DB_TYPE_HEAP; heap_hton->create = heap_create_handler; heap_hton->panic = heap_panic; heap_hton->flags = HTON_CAN_RECREATE; return 0; } static handler *heap_create_handler(handlerton *hton, TABLE_SHARE *table, bool, MEM_ROOT *mem_root) { return new (mem_root) ha_heap(hton, table); } /***************************************************************************** ** HEAP tables *****************************************************************************/ ha_heap::ha_heap(handlerton *hton, TABLE_SHARE *table_arg) : handler(hton, table_arg), file(0), records_changed(0), key_stat_version(0), single_instance(0) {} /* Hash index statistics is updated (copied from HP_KEYDEF::hash_buckets to records_per_key) after 1/HEAP_STATS_UPDATE_THRESHOLD fraction of table records have been inserted/updated/deleted. delete_all_rows() and table flush cause immediate update. NOTE hash index statistics must be updated when number of table records changes from 0 to non-zero value and vice versa. Otherwise records_in_range may erroneously return 0 and 'range' may miss records. */ #define HEAP_STATS_UPDATE_THRESHOLD 10 int ha_heap::open(const char *name, int mode, uint test_if_locked, const dd::Table *) { const bool delete_on_close = test_if_locked & HA_OPEN_INTERNAL_TABLE; single_instance = delete_on_close && table_share->ref_count() == 1; /* (1) if single instance it cannot possibly exist, create it. (2) otherwise it may exist, try to open it, if not found, create it */ if (single_instance || (!(file = heap_open(name, mode)) && my_errno() == ENOENT)) { HP_CREATE_INFO create_info; bool created_new_share; int rc; file = 0; if (heap_prepare_hp_create_info(table, single_instance, delete_on_close, &create_info)) goto end; create_info.pin_share = true; rc = heap_create(name, &create_info, &internal_share, &created_new_share); my_free(create_info.keydef); if (rc) goto end; implicit_emptied = created_new_share; if (single_instance) file = heap_open_from_share(internal_share, mode); else // open and register in list, so future opens can find it file = heap_open_from_share_and_register(internal_share, mode); if (!file) { heap_release_share(internal_share, single_instance); goto end; } } ref_length = sizeof(HP_HEAP_POSITION); /* We cannot run update_key_stats() here because we do not have a lock on the table. The 'records' count might just be changed temporarily at this moment and we might get wrong statistics (Bug #10178). Instead we request for update. This will be done in ha_heap::info(), which is always called before key statistics are used. */ key_stat_version = file->s->key_stat_version - 1; end: const int ret = file ? 0 : 1; DBUG_PRINT("heap_api", ("this=%p %s; return=%d", this, table_definition(name, table).c_str(), ret)); return (ret); } int ha_heap::close(void) { return single_instance ? hp_close(file) : // close without concurrency control heap_close(file); } /* Create a copy of this table DESCRIPTION Do same as default implementation but use file->s->name instead of table->s->path. This is needed by Windows where the clone() call sees '/'-delimited path in table->s->path, while ha_heap::open() was called with '\'-delimited path. */ handler *ha_heap::clone(const char *, MEM_ROOT *mem_root) { handler *new_handler = get_new_handler(table->s, false, mem_root, table->s->db_type()); if (new_handler && !new_handler->ha_open(table, file->s->name, table->db_stat, HA_OPEN_IGNORE_IF_LOCKED, NULL)) return new_handler; return NULL; /* purecov: inspected */ } const char *ha_heap::table_type() const { return "MEMORY"; } /** Update index statistics for the table. */ void ha_heap::update_key_stats() { for (uint i = 0; i < table->s->keys; i++) { KEY *key = table->key_info + i; key->set_in_memory_estimate(1.0); // Index is in memory if (!key->supports_records_per_key()) continue; if (key->algorithm != HA_KEY_ALG_BTREE) { if (key->flags & HA_NOSAME) key->set_records_per_key(key->user_defined_key_parts - 1, 1.0f); else { const ha_rows hash_buckets = file->s->keydef[i].hash_buckets; rec_per_key_t rec_per_key = hash_buckets ? static_cast(file->s->records) / hash_buckets : 2.0f; if (rec_per_key < 2.0f) rec_per_key = 2.0f; key->set_records_per_key(key->user_defined_key_parts - 1, rec_per_key); } } } records_changed = 0; /* At the end of update_key_stats() we can proudly claim they are OK. */ key_stat_version = file->s->key_stat_version; } int ha_heap::write_row(uchar *buf) { int res; ha_statistic_increment(&System_status_var::ha_write_count); if (table->next_number_field && buf == table->record[0]) { if ((res = update_auto_increment())) return res; } res = heap_write(file, buf); if (!res && (++records_changed * HEAP_STATS_UPDATE_THRESHOLD > file->s->records)) { /* We can perform this safely since only one writer at the time is allowed on the table. */ file->s->key_stat_version++; } DBUG_PRINT("heap_api", ("this=%p row=(%s); return=%d", this, row_to_string(buf, table).c_str(), res)); return res; } int ha_heap::update_row(const uchar *old_data, uchar *new_data) { int res; ha_statistic_increment(&System_status_var::ha_update_count); res = heap_update(file, old_data, new_data); if (!res && ++records_changed * HEAP_STATS_UPDATE_THRESHOLD > file->s->records) { /* We can perform this safely since only one writer at the time is allowed on the table. */ file->s->key_stat_version++; } return res; } int ha_heap::delete_row(const uchar *buf) { int res; ha_statistic_increment(&System_status_var::ha_delete_count); res = heap_delete(file, buf); if (!res && table->s->tmp_table == NO_TMP_TABLE && ++records_changed * HEAP_STATS_UPDATE_THRESHOLD > file->s->records) { /* We can perform this safely since only one writer at the time is allowed on the table. */ file->s->key_stat_version++; } return res; } int ha_heap::index_read_map(uchar *buf, const uchar *key, key_part_map keypart_map, enum ha_rkey_function find_flag) { DBUG_ASSERT(inited == INDEX); ha_statistic_increment(&System_status_var::ha_read_key_count); int error = heap_rkey(file, buf, active_index, key, keypart_map, find_flag); #ifndef DBUG_OFF const uint key_len = calculate_key_len(table, active_index, keypart_map); #endif /* DBUG_OFF */ DBUG_PRINT( "heap_api", ("this=%p cells=(%s) cells_len=%u find_flag=%s out=(%s); return=%d", this, indexed_cells_to_string(key, key_len, table->key_info[active_index]) .c_str(), key_len, ha_rkey_function_to_str(find_flag), (error == 0 ? row_to_string(buf, table).c_str() : ""), error)); return error; } int ha_heap::index_read_last_map(uchar *buf, const uchar *key, key_part_map keypart_map) { DBUG_ASSERT(inited == INDEX); ha_statistic_increment(&System_status_var::ha_read_key_count); int error = heap_rkey(file, buf, active_index, key, keypart_map, HA_READ_PREFIX_LAST); return error; } int ha_heap::index_read_idx_map(uchar *buf, uint index, const uchar *key, key_part_map keypart_map, enum ha_rkey_function find_flag) { ha_statistic_increment(&System_status_var::ha_read_key_count); int error = heap_rkey(file, buf, index, key, keypart_map, find_flag); return error; } int ha_heap::index_next(uchar *buf) { DBUG_ASSERT(inited == INDEX); ha_statistic_increment(&System_status_var::ha_read_next_count); int error = heap_rnext(file, buf); return error; } int ha_heap::index_prev(uchar *buf) { DBUG_ASSERT(inited == INDEX); ha_statistic_increment(&System_status_var::ha_read_prev_count); int error = heap_rprev(file, buf); return error; } int ha_heap::index_first(uchar *buf) { DBUG_ASSERT(inited == INDEX); ha_statistic_increment(&System_status_var::ha_read_first_count); int error = heap_rfirst(file, buf, active_index); return error; } int ha_heap::index_last(uchar *buf) { DBUG_ASSERT(inited == INDEX); ha_statistic_increment(&System_status_var::ha_read_last_count); int error = heap_rlast(file, buf, active_index); return error; } int ha_heap::rnd_init(bool scan) { return scan ? heap_scan_init(file) : 0; } int ha_heap::rnd_next(uchar *buf) { ha_statistic_increment(&System_status_var::ha_read_rnd_next_count); int error = heap_scan(file, buf); DBUG_PRINT("heap_api", ("this=%p out=(%s); return=%d", this, (error == 0 ? row_to_string(buf, table).c_str() : ""), error)); return error; } int ha_heap::rnd_pos(uchar *buf, uchar *pos) { int error; HP_HEAP_POSITION heap_position; ha_statistic_increment(&System_status_var::ha_read_rnd_count); memcpy(&heap_position, pos, sizeof(HP_HEAP_POSITION)); error = heap_rrnd(file, buf, &heap_position); return error; } void ha_heap::position(const uchar *) { heap_position(file, reinterpret_cast(ref)); // Ref is aligned } int ha_heap::info(uint flag) { HEAPINFO hp_info; (void)heap_info(file, &hp_info, flag); errkey = hp_info.errkey; stats.records = hp_info.records; stats.deleted = hp_info.deleted; stats.mean_rec_length = hp_info.reclength; stats.data_file_length = hp_info.data_length; stats.index_file_length = hp_info.index_length; stats.max_data_file_length = hp_info.max_records * hp_info.reclength; stats.delete_length = hp_info.deleted * hp_info.reclength; stats.create_time = (ulong)hp_info.create_time; if (flag & HA_STATUS_AUTO) stats.auto_increment_value = hp_info.auto_increment; stats.table_in_mem_estimate = 1.0; // Table entirely in memory /* If info() is called for the first time after open(), we will still have to update the key statistics. Hoping that a table lock is now in place. */ if (key_stat_version != file->s->key_stat_version) update_key_stats(); return 0; } int ha_heap::extra(enum ha_extra_function operation) { return heap_extra(file, operation); } int ha_heap::reset() { return heap_reset(file); } int ha_heap::delete_all_rows() { heap_clear(file); if (table->s->tmp_table == NO_TMP_TABLE) { /* We can perform this safely since only one writer at the time is allowed on the table. */ file->s->key_stat_version++; } return 0; } int ha_heap::external_lock(THD *, int) { return 0; // No external locking } /* Disable indexes. SYNOPSIS disable_indexes() mode mode of operation: HA_KEY_SWITCH_NONUNIQ disable all non-unique keys HA_KEY_SWITCH_ALL disable all keys HA_KEY_SWITCH_NONUNIQ_SAVE dis. non-uni. and make persistent HA_KEY_SWITCH_ALL_SAVE dis. all keys and make persistent DESCRIPTION Disable indexes and clear keys to use for scanning. IMPLEMENTATION HA_KEY_SWITCH_NONUNIQ is not implemented. HA_KEY_SWITCH_NONUNIQ_SAVE is not implemented with HEAP. HA_KEY_SWITCH_ALL_SAVE is not implemented with HEAP. RETURN 0 ok HA_ERR_WRONG_COMMAND mode not implemented. */ int ha_heap::disable_indexes(uint mode) { int error; if (mode == HA_KEY_SWITCH_ALL) { error = heap_disable_indexes(file); } else { /* mode not implemented */ error = HA_ERR_WRONG_COMMAND; } return error; } /* Enable indexes. SYNOPSIS enable_indexes() mode mode of operation: HA_KEY_SWITCH_NONUNIQ enable all non-unique keys HA_KEY_SWITCH_ALL enable all keys HA_KEY_SWITCH_NONUNIQ_SAVE en. non-uni. and make persistent HA_KEY_SWITCH_ALL_SAVE en. all keys and make persistent DESCRIPTION Enable indexes and set keys to use for scanning. The indexes might have been disabled by disable_index() before. The function works only if both data and indexes are empty, since the heap storage engine cannot repair the indexes. To be sure, call handler::delete_all_rows() before. IMPLEMENTATION HA_KEY_SWITCH_NONUNIQ is not implemented. HA_KEY_SWITCH_NONUNIQ_SAVE is not implemented with HEAP. HA_KEY_SWITCH_ALL_SAVE is not implemented with HEAP. RETURN 0 ok HA_ERR_CRASHED data or index is non-empty. Delete all rows and retry. HA_ERR_WRONG_COMMAND mode not implemented. */ int ha_heap::enable_indexes(uint mode) { int error; if (mode == HA_KEY_SWITCH_ALL) { error = heap_enable_indexes(file); } else { /* mode not implemented */ error = HA_ERR_WRONG_COMMAND; } return error; } /* Test if indexes are disabled. SYNOPSIS indexes_are_disabled() no parameters RETURN 0 indexes are not disabled 1 all indexes are disabled [2 non-unique indexes are disabled - NOT YET IMPLEMENTED] */ int ha_heap::indexes_are_disabled(void) { return heap_indexes_are_disabled(file); } THR_LOCK_DATA **ha_heap::store_lock(THD *, THR_LOCK_DATA **to, enum thr_lock_type lock_type) { /* This method should not be called for internal temporary tables as they don't have properly initialized THR_LOCK and THR_LOCK_DATA structures. */ DBUG_ASSERT(!single_instance); if (lock_type != TL_IGNORE && file->lock.type == TL_UNLOCK) file->lock.type = lock_type; *to++ = &file->lock; return to; } /* We have to ignore ENOENT entries as the HEAP table is created on open and not when doing a CREATE on the table. */ int ha_heap::delete_table(const char *name, const dd::Table *) { int error = heap_delete_table(name); return error == ENOENT ? 0 : error; } void ha_heap::drop_table(const char *) { file->s->delete_on_close = 1; close(); } int ha_heap::rename_table(const char *from, const char *to, const dd::Table *, dd::Table *) { return heap_rename(from, to); } ha_rows ha_heap::records_in_range(uint inx, key_range *min_key, key_range *max_key) { KEY *key = table->key_info + inx; if (key->algorithm == HA_KEY_ALG_BTREE) return hp_rb_records_in_range(file, inx, min_key, max_key); if (!min_key || !max_key || min_key->length != max_key->length || min_key->length != key->key_length || min_key->flag != HA_READ_KEY_EXACT || max_key->flag != HA_READ_AFTER_KEY) return HA_POS_ERROR; // Can only use exact keys if (stats.records <= 1) return stats.records; /* Assert that info() did run. We need current statistics here. */ DBUG_ASSERT(key_stat_version == file->s->key_stat_version); const ha_rows rec_in_range = static_cast( key->records_per_key(key->user_defined_key_parts - 1)); return rec_in_range; } static int heap_prepare_hp_create_info(TABLE *table_arg, bool single_instance, bool delete_on_close, HP_CREATE_INFO *hp_create_info) { uint key, parts, mem_per_row = 0, keys = table_arg->s->keys; uint auto_key = 0, auto_key_type = 0; ha_rows max_rows; HP_KEYDEF *keydef; HA_KEYSEG *seg; TABLE_SHARE *share = table_arg->s; bool found_real_auto_increment = 0; memset(hp_create_info, 0, sizeof(*hp_create_info)); for (key = parts = 0; key < keys; key++) parts += table_arg->key_info[key].user_defined_key_parts; if (!(keydef = (HP_KEYDEF *)my_malloc( hp_key_memory_HP_KEYDEF, keys * sizeof(HP_KEYDEF) + parts * sizeof(HA_KEYSEG), MYF(MY_WME)))) return my_errno(); seg = reinterpret_cast(keydef + keys); for (key = 0; key < keys; key++) { KEY *pos = table_arg->key_info + key; KEY_PART_INFO *key_part = pos->key_part; KEY_PART_INFO *key_part_end = key_part + pos->user_defined_key_parts; keydef[key].keysegs = (uint)pos->user_defined_key_parts; keydef[key].flag = (pos->flags & (HA_NOSAME | HA_NULL_ARE_EQUAL)); keydef[key].seg = seg; switch (pos->algorithm) { case HA_KEY_ALG_HASH: keydef[key].algorithm = HA_KEY_ALG_HASH; mem_per_row += sizeof(HASH_INFO); break; case HA_KEY_ALG_BTREE: keydef[key].algorithm = HA_KEY_ALG_BTREE; mem_per_row += sizeof(TREE_ELEMENT) + pos->key_length + sizeof(char *); break; default: DBUG_ASSERT(0); // cannot happen } for (; key_part != key_part_end; key_part++, seg++) { Field *field = key_part->field; if (pos->algorithm == HA_KEY_ALG_BTREE) seg->type = field->key_type(); else { if ((seg->type = field->key_type()) != (int)HA_KEYTYPE_TEXT && seg->type != HA_KEYTYPE_VARTEXT1 && seg->type != HA_KEYTYPE_VARTEXT2 && seg->type != HA_KEYTYPE_VARBINARY1 && seg->type != HA_KEYTYPE_VARBINARY2) seg->type = HA_KEYTYPE_BINARY; } seg->start = (uint)key_part->offset; seg->length = (uint)key_part->length; seg->flag = key_part->key_part_flag; if (field->flags & (ENUM_FLAG | SET_FLAG)) seg->charset = &my_charset_bin; else seg->charset = field->charset_for_protocol(); if (field->real_maybe_null()) { seg->null_bit = field->null_bit; seg->null_pos = field->null_offset(); } else { seg->null_bit = 0; seg->null_pos = 0; } if (field->flags & AUTO_INCREMENT_FLAG && table_arg->found_next_number_field && key == share->next_number_index) { /* Store key number and type for found auto_increment key We have to store type as seg->type can differ from it */ auto_key = key + 1; auto_key_type = field->key_type(); } } } mem_per_row += MY_ALIGN(share->reclength + 1, sizeof(char *)); if (table_arg->found_next_number_field) { keydef[share->next_number_index].flag |= HA_AUTO_KEY; found_real_auto_increment = share->next_number_key_offset == 0; } hp_create_info->auto_key = auto_key; hp_create_info->auto_key_type = auto_key_type; hp_create_info->max_table_size = current_thd->variables.max_heap_table_size; hp_create_info->with_auto_increment = found_real_auto_increment; hp_create_info->single_instance = single_instance; hp_create_info->delete_on_close = delete_on_close; max_rows = (ha_rows)(hp_create_info->max_table_size / mem_per_row); if (share->max_rows && share->max_rows < max_rows) max_rows = share->max_rows; hp_create_info->max_records = (ulong)max_rows; hp_create_info->min_records = (ulong)share->min_rows; hp_create_info->keys = share->keys; hp_create_info->reclength = share->reclength; hp_create_info->keydef = keydef; return 0; } int ha_heap::create(const char *name, TABLE *table_arg, HA_CREATE_INFO *create_info, dd::Table *) { int error; bool created; HP_CREATE_INFO hp_create_info; DBUG_ASSERT(!single_instance); error = heap_prepare_hp_create_info(table_arg, false, false, &hp_create_info); if (error == 0) { hp_create_info.auto_increment = (create_info->auto_increment_value ? create_info->auto_increment_value - 1 : 0); error = heap_create(name, &hp_create_info, &internal_share, &created); my_free(hp_create_info.keydef); DBUG_ASSERT(file == 0); } DBUG_PRINT("heap_api", ("this=%p %s; return=%d", this, table_definition(name, table_arg).c_str(), error)); return (error); } void ha_heap::update_create_info(HA_CREATE_INFO *create_info) { table->file->info(HA_STATUS_AUTO); if (!(create_info->used_fields & HA_CREATE_USED_AUTO)) create_info->auto_increment_value = stats.auto_increment_value; } void ha_heap::get_auto_increment(ulonglong, ulonglong, ulonglong, ulonglong *first_value, ulonglong *nb_reserved_values) { ha_heap::info(HA_STATUS_AUTO); *first_value = stats.auto_increment_value; /* such table has only table-level locking so reserves up to +inf */ *nb_reserved_values = ULLONG_MAX; } bool ha_heap::check_if_incompatible_data(HA_CREATE_INFO *info, uint table_changes) { /* Check that auto_increment value was not changed */ if ((info->used_fields & HA_CREATE_USED_AUTO && info->auto_increment_value != 0) || table_changes == IS_EQUAL_NO || table_changes & IS_EQUAL_PACK_LENGTH) // Not implemented yet return COMPATIBLE_DATA_NO; return COMPATIBLE_DATA_YES; } struct st_mysql_storage_engine heap_storage_engine = { MYSQL_HANDLERTON_INTERFACE_VERSION}; mysql_declare_plugin(heap){ MYSQL_STORAGE_ENGINE_PLUGIN, &heap_storage_engine, "MEMORY", "MySQL AB", "Hash based, stored in memory, useful for temporary tables", PLUGIN_LICENSE_GPL, heap_init, NULL, NULL, 0x0100, /* 1.0 */ NULL, /* status variables */ NULL, /* system variables */ NULL, /* config options */ 0, /* flags */ } mysql_declare_plugin_end;