MDEV-18295 IMPORT TABLESPACE fails with instant-altered tables

When importing a tablespace, we must initialize dummy DEFAULT NULL values for any instantly added columns in order to avoid a debug assertion failure when PageConverter::update_records() invokes rec_get_offsets(). Finally, when the operation completes, we must evict and reload the table definition, so that the correct default values for instantly added columns will be loaded. ha_innobase::discard_or_import_tablespace(): On successful IMPORT TABLESPACE, evict and reload the table definition, so that btr_cur_instant_init() will load the correct metadata. PageConverter::update_index_page(): Fill in dummy DEFAULT NULL values for instantly added columns. These will be replaced upon the completion of the operation by evicting and reloading the metadata. row_discard_tablespace(): Invoke dict_table_t::remove_instant(). After DISCARD TABLESPACE, the table is no longer in "instant ALTER" format, because there is no data file attached.

Author: dr-m

mysql-test/suite/innodb/r/instant_alter_import.result

@@ -0,0 +1,46 @@
+set default_storage_engine=innodb;
+#
+# MDEV-18295 IMPORT TABLESPACE fails with instant-altered tables
+#
+create table t2 (x int, z int default 41);
+alter table t2 discard tablespace;
+create table t1 (x int);
+insert into t1 values (1);
+alter table t1 add z int default 42, algorithm instant;
+select * from t1;
+x	z
+1	42
+flush tables t1 for export;
+unlock tables;
+# The metadata has to be updated to instant ADD COLUMN.
+alter table t2 import tablespace;
+select * from t2;
+x	z
+1	42
+insert into t2 set x=2;
+select * from t2;
+x	z
+1	42
+2	41
+alter table t1 discard tablespace;
+flush tables t2 for export;
+unlock tables;
+# Both the metadata and the data file used instant ADD COLUMN.
+alter table t1 import tablespace;
+select * from t1;
+x	z
+1	42
+2	41
+drop table t2;
+create table t2 select * from t1;
+alter table t1 discard tablespace;
+flush tables t2 for export;
+unlock tables;
+# The instant ADD COLUMN has to be removed from the metadata.
+alter table t1 import tablespace;
+select * from t1;
+x	z
+1	42
+2	41
+drop table t2;
+drop table t1;

mysql-test/suite/innodb/t/instant_alter_import.test

@@ -0,0 +1,52 @@
+--source include/have_innodb.inc
+set default_storage_engine=innodb;
+
+--echo #
+--echo # MDEV-18295 IMPORT TABLESPACE fails with instant-altered tables
+--echo #
+
+create table t2 (x int, z int default 41);
+alter table t2 discard tablespace;
+
+create table t1 (x int);
+insert into t1 values (1);
+alter table t1 add z int default 42, algorithm instant;
+select * from t1;
+flush tables t1 for export;
+--let $MYSQLD_DATADIR= `select @@datadir`
+--move_file $MYSQLD_DATADIR/test/t1.cfg $MYSQLD_DATADIR/test/t2.cfg
+--copy_file $MYSQLD_DATADIR/test/t1.ibd $MYSQLD_DATADIR/test/t2.ibd
+unlock tables;
+
+--echo # The metadata has to be updated to instant ADD COLUMN.
+alter table t2 import tablespace;
+
+select * from t2;
+insert into t2 set x=2;
+select * from t2;
+
+alter table t1 discard tablespace;
+flush tables t2 for export;
+--move_file $MYSQLD_DATADIR/test/t2.cfg $MYSQLD_DATADIR/test/t1.cfg
+--copy_file $MYSQLD_DATADIR/test/t2.ibd $MYSQLD_DATADIR/test/t1.ibd
+unlock tables;
+
+--echo # Both the metadata and the data file used instant ADD COLUMN.
+alter table t1 import tablespace;
+select * from t1;
+
+drop table t2;
+create table t2 select * from t1;
+
+alter table t1 discard tablespace;
+flush tables t2 for export;
+--move_file $MYSQLD_DATADIR/test/t2.cfg $MYSQLD_DATADIR/test/t1.cfg
+--copy_file $MYSQLD_DATADIR/test/t2.ibd $MYSQLD_DATADIR/test/t1.ibd
+unlock tables;
+
+--echo # The instant ADD COLUMN has to be removed from the metadata.
+alter table t1 import tablespace;
+select * from t1;
+
+drop table t2;
+drop table t1;

storage/innobase/handler/ha_innodb.cc

@@ -4,7 +4,7 @@ Copyright (c) 2000, 2018, Oracle and/or its affiliates. All Rights Reserved.
 Copyright (c) 2008, 2009 Google Inc.
 Copyright (c) 2009, Percona Inc.
 Copyright (c) 2012, Facebook Inc.
-Copyright (c) 2013, 2018, MariaDB Corporation.
+Copyright (c) 2013, 2019, MariaDB Corporation.
 
 Portions of this file contain modifications contributed and copyrighted by
 Google, Inc. Those modifications are gratefully acknowledged and are described
@@ -12682,22 +12682,19 @@ ha_innobase::discard_or_import_tablespace(
 DBUG_RETURN(HA_ERR_TABLE_READONLY);
 }
 
-dict_table_t*	dict_table = m_prebuilt->table;
-
-if (dict_table->is_temporary()) {
-
+if (m_prebuilt->table->is_temporary()) {
 ib_senderrf(
 m_prebuilt->trx->mysql_thd, IB_LOG_LEVEL_ERROR,
 ER_CANNOT_DISCARD_TEMPORARY_TABLE);
 
 DBUG_RETURN(HA_ERR_TABLE_NEEDS_UPGRADE);
 }
 
-if (dict_table->space == fil_system.sys_space) {
+if (m_prebuilt->table->space == fil_system.sys_space) {
 ib_senderrf(
 m_prebuilt->trx->mysql_thd, IB_LOG_LEVEL_ERROR,
 ER_TABLE_IN_SYSTEM_TABLESPACE,
-dict_table->name.m_name);
+m_prebuilt->table->name.m_name);
 
 DBUG_RETURN(HA_ERR_TABLE_NEEDS_UPGRADE);
 }
@@ -12706,7 +12703,7 @@ ha_innobase::discard_or_import_tablespace(
 
 /* Obtain an exclusive lock on the table. */
 dberr_t	err = row_mysql_lock_table(
-m_prebuilt->trx, dict_table, LOCK_X,
+m_prebuilt->trx, m_prebuilt->table, LOCK_X,
 discard ? "setting table lock for DISCARD TABLESPACE"
 : "setting table lock for IMPORT TABLESPACE");
 
@@ -12719,32 +12716,32 @@ ha_innobase::discard_or_import_tablespace(
 user may want to set the DISCARD flag in order to IMPORT
 a new tablespace. */
 
-if (!dict_table->is_readable()) {
+if (!m_prebuilt->table->is_readable()) {
 ib_senderrf(
 m_prebuilt->trx->mysql_thd,
 IB_LOG_LEVEL_WARN, ER_TABLESPACE_MISSING,
-dict_table->name.m_name);
+m_prebuilt->table->name.m_name);
 }
 
 err = row_discard_tablespace_for_mysql(
-dict_table->name.m_name, m_prebuilt->trx);
+m_prebuilt->table->name.m_name, m_prebuilt->trx);
 
-} else if (dict_table->is_readable()) {
+} else if (m_prebuilt->table->is_readable()) {
 /* Commit the transaction in order to
 release the table lock. */
 trx_commit_for_mysql(m_prebuilt->trx);
 
 ib::error() << "Unable to import tablespace "
-<< dict_table->name << " because it already"
+<< m_prebuilt->table->name << " because it already"
 " exists. Please DISCARD the tablespace"
 " before IMPORT.";
 ib_senderrf(
 m_prebuilt->trx->mysql_thd, IB_LOG_LEVEL_ERROR,
-ER_TABLESPACE_EXISTS, dict_table->name.m_name);
+ER_TABLESPACE_EXISTS, m_prebuilt->table->name.m_name);
 
 DBUG_RETURN(HA_ERR_TABLE_EXIST);
 } else {
-err = row_import_for_mysql(dict_table, m_prebuilt);
+err = row_import_for_mysql(m_prebuilt->table, m_prebuilt);
 
 if (err == DB_SUCCESS) {
 
@@ -12760,12 +12757,35 @@ ha_innobase::discard_or_import_tablespace(
 /* Commit the transaction in order to release the table lock. */
 trx_commit_for_mysql(m_prebuilt->trx);
 
-if (err == DB_SUCCESS && !discard
- && dict_stats_is_persistent_enabled(dict_table)) {
+if (discard || err != DB_SUCCESS) {
+DBUG_RETURN(convert_error_code_to_mysql(
+ err, m_prebuilt->table->flags, NULL));
+}
+
+/* Evict and reload the table definition in order to invoke
+btr_cur_instant_init(). */
+table_id_t id = m_prebuilt->table->id;
+ut_ad(id);
+mutex_enter(&dict_sys->mutex);
+dict_table_close(m_prebuilt->table, TRUE, FALSE);
+dict_table_remove_from_cache(m_prebuilt->table);
+m_prebuilt->table = dict_table_open_on_id(id, TRUE,
+ DICT_TABLE_OP_NORMAL);
+mutex_exit(&dict_sys->mutex);
+if (!m_prebuilt->table) {
+err = DB_TABLE_NOT_FOUND;
+} else {
+if (const Field* ai = table->found_next_number_field) {
+initialize_auto_increment(m_prebuilt->table, ai);
+}
+dict_stats_init(m_prebuilt->table);
+}
+
+if (dict_stats_is_persistent_enabled(m_prebuilt->table)) {
 dberr_t	ret;
 
 /* Adjust the persistent statistics. */
-ret = dict_stats_update(dict_table,
+ret = dict_stats_update(m_prebuilt->table,
 DICT_STATS_RECALC_PERSISTENT);
 
 if (ret != DB_SUCCESS) {
@@ -12775,11 +12795,12 @@ ha_innobase::discard_or_import_tablespace(
 ER_ALTER_INFO,
 "Error updating stats for table '%s'"
 " after table rebuild: %s",
-dict_table->name.m_name, ut_strerr(ret));
+m_prebuilt->table->name.m_name,
+ut_strerr(ret));
 }
 }
 
-DBUG_RETURN(convert_error_code_to_mysql(err, dict_table->flags, NULL));
+DBUG_RETURN(0);
 }
 
 /**

storage/innobase/row/row0import.cc

@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 2012, 2016, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2015, 2018, MariaDB Corporation.
+Copyright (c) 2015, 2019, 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
@@ -1820,13 +1820,22 @@ PageConverter::update_index_page(
 
 if (dict_index_is_clust(m_index->m_srv_index)) {
 if (page_is_root(page)) {
+dict_index_t* index = const_cast<dict_index_t*>(
+m_index->m_srv_index);
 /* Preserve the PAGE_ROOT_AUTO_INC. */
-if (m_index->m_srv_index->table->supports_instant()
- && btr_cur_instant_root_init(
- const_cast<dict_index_t*>(
- m_index->m_srv_index),
- page)) {
-return(DB_CORRUPTION);
+if (index->table->supports_instant()) {
+if (btr_cur_instant_root_init(index, page)) {
+return(DB_CORRUPTION);
+}
+
+/* Provisionally set all instantly
+added columns to be DEFAULT NULL. */
+for (unsigned i = index->n_core_fields;
+ i < index->n_fields; i++) {
+dict_col_t* col = index->fields[i].col;
+col->def_val.len = UNIV_SQL_NULL;
+col->def_val.data = NULL;
+}
 }
 } else {
 /* Clear PAGE_MAX_TRX_ID so that it can be

storage/innobase/row/row0mysql.cc

@@ -3074,13 +3074,14 @@ row_discard_tablespace(
 table->flags2 |= DICT_TF2_DISCARDED;
 dict_table_change_id_in_cache(table, new_id);
 
-/* Reset the root page numbers. */
+dict_index_t* index = UT_LIST_GET_FIRST(table->indexes);
+if (index) index->remove_instant();
 
-for (dict_index_t* index = UT_LIST_GET_FIRST(table->indexes);
- index != 0;
- index = UT_LIST_GET_NEXT(indexes, index)) {
+/* Reset the root page numbers. */
+for (; index; index = UT_LIST_GET_NEXT(indexes, index)) {
 index->page = FIL_NULL;
 }
+
 /* If the tablespace did not already exist or we couldn't
 write to it, we treat that as a successful DISCARD. It is
 unusable anyway. */