OceanBase 回收站功能(社区版4.2.1.0)

概述

回收站默认是关闭的。如果开启的话，回收站里包含 OB 被删除的对象(租户，表，索引，database等)。当删除OB某个对象后，该对象会进入回收站，删除对象的存储空间并不会被释放，仍然占用物理空间。

开启回收站

使用 sys租户 或者 用户租户的管理员 登录修改

[root@rac1 ~]# obclient -h10.0.0.197 -P2883 -uroot@sys#myoceanbase -p'aaAA11__' -Doceanbase -A -c;
Welcome to the OceanBase.  Commands end with ; or \g.
Your OceanBase connection id is 524910
Server version: OceanBase_CE 4.2.1.0 (r100000102023092807-7b0f43693565654bb1d7343f728bc2013dfff959) (Built Sep 28 2023 07:25:28)Copyright (c) 2000, 2018, OceanBase and/or its affiliates. All rights reserved.Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]>  SET GLOBAL recyclebin = on;
Query OK, 0 rows affected (0.052 sec)obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> exit
Bye
[root@rac1 ~]# obclient -h10.0.0.197 -P2883 -uroot@mysqlbak#myoceanbase -p'aaAA11__' -Doceanbase -A -c;
Welcome to the OceanBase.  Commands end with ; or \g.
Your OceanBase connection id is 524911
Server version: OceanBase_CE 4.2.1.0 (r100000102023092807-7b0f43693565654bb1d7343f728bc2013dfff959) (Built Sep 28 2023 07:25:28)Copyright (c) 2000, 2018, OceanBase and/or its affiliates. All rights reserved.Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> SET GLOBAL recyclebin = on;
Query OK, 0 rows affected (0.030 sec)obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> exit
Bye
[root@rac1 ~]#

恢复租户

删除租户

只有 sys 租户 可以进行删除租户的操作，使用回收站查看 被删除的租户 需要 通过 sys 租户 登录 查看， 如果删除对象属于 数据库(database), 表 等对象。使用 sys租户 和 相关租户的管理员查看均可

使用 sys租户登录 删除 其它租户

[root@rac1 ~]# obclient -h10.0.0.197 -P2883 -uroot@sys#myoceanbase -p'aaAA11__' -Doceanbase -A -c;
Welcome to the OceanBase.  Commands end with ; or \g.
Your OceanBase connection id is 524912
Server version: OceanBase_CE 4.2.1.0 (r100000102023092807-7b0f43693565654bb1d7343f728bc2013dfff959) (Built Sep 28 2023 07:25:28)Copyright (c) 2000, 2018, OceanBase and/or its affiliates. All rights reserved.Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> SET GLOBAL recyclebin = 1;
Query OK, 0 rows affected (0.003 sec)obclient [oceanbase]>
obclient [oceanbase]> SET GLOBAL recyclebin = true;
Query OK, 0 rows affected (0.003 sec)obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> SHOW RECYCLEBIN;
Empty set (0.005 sec)obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> drop TENANT mysqlbak;
Query OK, 0 rows affected (0.050 sec)obclient [oceanbase]>
obclient [oceanbase]>

查看回收站

可以发现 被删租户mysqlbak 已被放入回收站

obclient [oceanbase]> SHOW RECYCLEBIN;
+-----------------------------------------+---------------+--------+----------------------------+
| OBJECT_NAME                             | ORIGINAL_NAME | TYPE   | CREATETIME                 |
+-----------------------------------------+---------------+--------+----------------------------+
| __recycle_$_1715845727_1715862359970160 | mysqlbak      | TENANT | 2024-05-17 10:46:56.072550 |
+-----------------------------------------+---------------+--------+----------------------------+
1 row in set (0.005 sec)

通过租户名恢复
[root@rac1 ~]# obclient -h10.0.0.197 -P2883 -uroot@sys#myoceanbase -p'aaAA11__' -Doceanbase -A -c;
Welcome to the OceanBase.  Commands end with ; or \g.
Your OceanBase connection id is 524949
Server version: OceanBase_CE 4.2.1.0 (r100000102023092807-7b0f43693565654bb1d7343f728bc2013dfff959) (Built Sep 28 2023 07:25:28)Copyright (c) 2000, 2018, OceanBase and/or its affiliates. All rights reserved.Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> SHOW RECYCLEBIN;
+-----------------------------------------+---------------+--------+----------------------------+
| OBJECT_NAME                             | ORIGINAL_NAME | TYPE   | CREATETIME                 |
+-----------------------------------------+---------------+--------+----------------------------+
| __recycle_$_1715845727_1715862359970160 | mysqlbak      | TENANT | 2024-05-17 10:46:56.072550 |
+-----------------------------------------+---------------+--------+----------------------------+
1 row in set (0.006 sec)obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> FLASHBACK TENANT mysqlbak TO BEFORE DROP;
Query OK, 0 rows affected (0.032 sec)obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> exit
Bye
[root@rac1 ~]# obclient -h10.0.0.197 -P2883 -uroot@mysqlbak#myoceanbase -p'aaAA11__' -Doceanbase -A -c;
Welcome to the OceanBase.  Commands end with ; or \g.
Your OceanBase connection id is 524950
Server version: OceanBase_CE 4.2.1.0 (r100000102023092807-7b0f43693565654bb1d7343f728bc2013dfff959) (Built Sep 28 2023 07:25:28)Copyright (c) 2000, 2018, OceanBase and/or its affiliates. All rights reserved.Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.obclient [oceanbase]>

通过回收站中的名称恢复

由于 被删租户 在 回收站 的名称是 全局唯一的 ，因此强烈建议 使用 回收站中的名称恢复

[root@rac1 ~]# obclient -h10.0.0.197 -P2883 -uroot@sys#myoceanbase -p'aaAA11__' -Doceanbase -A -c;
Welcome to the OceanBase.  Commands end with ; or \g.
Your OceanBase connection id is 524951
Server version: OceanBase_CE 4.2.1.0 (r100000102023092807-7b0f43693565654bb1d7343f728bc2013dfff959) (Built Sep 28 2023 07:25:28)Copyright (c) 2000, 2018, OceanBase and/or its affiliates. All rights reserved.Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.obclient [oceanbase]> drop TENANT mysqlbak;
Query OK, 0 rows affected (0.025 sec)obclient [oceanbase]> SHOW RECYCLEBIN;
+-----------------------------------------+---------------+--------+----------------------------+
| OBJECT_NAME                             | ORIGINAL_NAME | TYPE   | CREATETIME                 |
+-----------------------------------------+---------------+--------+----------------------------+
| __recycle_$_1715845727_1715916550830336 | mysqlbak      | TENANT | 2024-05-17 11:33:18.441053 |
+-----------------------------------------+---------------+--------+----------------------------+
1 row in set (0.005 sec)obclient [oceanbase]>
obclient [oceanbase]> FLASHBACK TENANT __recycle_$_1715845727_1715916550830336 TO BEFORE DROP;
Query OK, 0 rows affected (0.026 sec)

恢复被删租户之后重命名

使用租户名还原之后重命名

[root@rac1 ~]# obclient -h10.0.0.197 -P2883 -uroot@sys#myoceanbase -p'aaAA11__' -Doceanbase -A -c;
Welcome to the OceanBase.  Commands end with ; or \g.
Your OceanBase connection id is 524955
Server version: OceanBase_CE 4.2.1.0 (r100000102023092807-7b0f43693565654bb1d7343f728bc2013dfff959) (Built Sep 28 2023 07:25:28)Copyright (c) 2000, 2018, OceanBase and/or its affiliates. All rights reserved.Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.obclient [oceanbase]>
obclient [oceanbase]> drop TENANT mysqlbak;
Query OK, 0 rows affected (0.028 sec)obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> SHOW RECYCLEBIN;
+-----------------------------------------+---------------+--------+----------------------------+
| OBJECT_NAME                             | ORIGINAL_NAME | TYPE   | CREATETIME                 |
+-----------------------------------------+---------------+--------+----------------------------+
| __recycle_$_1715845727_1715916858016656 | mysqlbak      | TENANT | 2024-05-17 11:38:45.554886 |
+-----------------------------------------+---------------+--------+----------------------------+
1 row in set (0.007 sec)obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> FLASHBACK TENANT mysqlbak  TO BEFORE DROP RENAME TO obmysql;
Query OK, 0 rows affected (0.021 sec)obclient [oceanbase]>
obclient [oceanbase]>

使用回收站名称还原租户重命名
[root@rac1 ~]# obclient -h10.0.0.197 -P2883 -uroot@sys#myoceanbase -p'aaAA11__' -Doceanbase -A -c;
Welcome to the OceanBase.  Commands end with ; or \g.
Your OceanBase connection id is 524961
Server version: OceanBase_CE 4.2.1.0 (r100000102023092807-7b0f43693565654bb1d7343f728bc2013dfff959) (Built Sep 28 2023 07:25:28)Copyright (c) 2000, 2018, OceanBase and/or its affiliates. All rights reserved.Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> drop TENANT obmysql;
Query OK, 0 rows affected (0.027 sec)obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> SHOW RECYCLEBIN;
+-----------------------------------------+---------------+--------+----------------------------+
| OBJECT_NAME                             | ORIGINAL_NAME | TYPE   | CREATETIME                 |
+-----------------------------------------+---------------+--------+----------------------------+
| __recycle_$_1715845727_1715917204567576 | obmysql       | TENANT | 2024-05-17 11:42:52.154001 |
+-----------------------------------------+---------------+--------+----------------------------+
1 row in set (0.004 sec)obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> FLASHBACK TENANT __recycle_$_1715845727_1715917204567576  TO BEFORE DROP RENAME TO mysqlbak;
Query OK, 0 rows affected (0.024 sec)obclient [oceanbase]>

恢复数据库(database)

恢复数据时 不允许使用 数据库原始名称，只能使用 回收站名称 来恢复, 并且恢复后的数据库名称不能与已有数据库名称重复

恢复数据库

使用 sys租户 或者 MySQL租户的管理员 登录进行恢复

[root@rac1 ~]# obclient -h10.0.0.197 -P2883 -uroot@mysqlbak#myoceanbase -p'aaAA11__' -Doceanbase -A -c;
Welcome to the OceanBase.  Commands end with ; or \g.
Your OceanBase connection id is 524962
Server version: OceanBase_CE 4.2.1.0 (r100000102023092807-7b0f43693565654bb1d7343f728bc2013dfff959) (Built Sep 28 2023 07:25:28)Copyright (c) 2000, 2018, OceanBase and/or its affiliates. All rights reserved.Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.obclient [oceanbase]>
obclient [oceanbase]> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| oceanbase          |
| test               |
+--------------------+
4 rows in set (0.007 sec)obclient [oceanbase]>
obclient [oceanbase]> drop database test;
Query OK, 0 rows affected (0.031 sec)obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> SHOW RECYCLEBIN;
+-----------------------------------------+---------------+----------+----------------------------+
| OBJECT_NAME                             | ORIGINAL_NAME | TYPE     | CREATETIME                 |
+-----------------------------------------+---------------+----------+----------------------------+
| __recycle_$_1715845727_1715917792242600 | test          | DATABASE | 2024-05-17 11:49:52.243462 |
+-----------------------------------------+---------------+----------+----------------------------+
1 row in set (0.007 sec)obclient [oceanbase]>
obclient [oceanbase]> FLASHBACK DATABASE __recycle_$_1715845727_1715917792242600 TO BEFORE DROP;
Query OK, 0 rows affected (0.034 sec)obclient [oceanbase]>
obclient [oceanbase]>
obclient [oceanbase]> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| oceanbase          |
| test               |
+--------------------+
4 rows in set (0.006 sec)

恢复数据库并重命名
obclient [oceanbase]> drop database test;
Query OK, 0 rows affected (0.030 sec)obclient [oceanbase]>
obclient [oceanbase]> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| oceanbase          |
+--------------------+
3 rows in set (0.006 sec)obclient [oceanbase]>
obclient [oceanbase]> SHOW RECYCLEBIN;
+-----------------------------------------+---------------+----------+----------------------------+
| OBJECT_NAME                             | ORIGINAL_NAME | TYPE     | CREATETIME                 |
+-----------------------------------------+---------------+----------+----------------------------+
| __recycle_$_1715845727_1715918146268704 | test          | DATABASE | 2024-05-17 11:55:46.268177 |
+-----------------------------------------+---------------+----------+----------------------------+
1 row in set (0.006 sec)obclient [oceanbase]>
obclient [oceanbase]> FLASHBACK DATABASE __recycle_$_1715845727_1715918146268704 TO BEFORE DROP RENAME TO ceshi;
Query OK, 0 rows affected (0.029 sec)obclient [oceanbase]>
obclient [oceanbase]> show databases;
+--------------------+
| Database           |
+--------------------+
| ceshi              |
| information_schema |
| mysql              |
| oceanbase          |
+--------------------+
4 rows in set (0.006 sec)obclient [oceanbase]>

恢复表

使用 sys租户，MySQL 用户租户 和 Oracle 用户租户 均可以从回收站中 恢复表。恢复时可修改表的名称，但是不能与已有表重名

删除表

当删除某个表时，表中的 索引 会随着表 一起进入回收站。

obclient [tpcc]> drop table bmsql_item;
Query OK, 0 rows affected (0.040 sec)obclient [tpcc]>
obclient [tpcc]>
obclient [tpcc]>
obclient [tpcc]> SHOW RECYCLEBIN;
+-----------------------------------------+-----------------------+-------+----------------------------+
| OBJECT_NAME                             | ORIGINAL_NAME         | TYPE  | CREATETIME                 |
+-----------------------------------------+-----------------------+-------+----------------------------+
| __recycle_$_1715845727_1715925641147936 | __idx_500011_index_id | INDEX | 2024-05-17 14:00:41.147178 |
| __recycle_$_1715845727_1715925641155432 | bmsql_item            | TABLE | 2024-05-17 14:00:41.154715 |
+-----------------------------------------+-----------------------+-------+----------------------------+
2 rows in set (0.006 sec)obclient [tpcc]>

恢复表

还原表时可以使用 表名 和 回收站中的名称 还原，与 还原租户 一样，建议使用 回收站中的名称还原。可以发现，还原表时，原表自带的索引也会随着表一起被还原。

obclient [tpcc]> SHOW RECYCLEBIN;
+-----------------------------------------+-----------------------+-------+----------------------------+
| OBJECT_NAME                             | ORIGINAL_NAME         | TYPE  | CREATETIME                 |
+-----------------------------------------+-----------------------+-------+----------------------------+
| __recycle_$_1715845727_1715925641147936 | __idx_500011_index_id | INDEX | 2024-05-17 14:00:41.147178 |
| __recycle_$_1715845727_1715925641155432 | bmsql_item            | TABLE | 2024-05-17 14:00:41.154715 |
+-----------------------------------------+-----------------------+-------+----------------------------+
2 rows in set (0.006 sec)obclient [tpcc]>
obclient [tpcc]> FLASHBACK TABLE __recycle_$_1715845727_1715925641155432 TO BEFORE DROP;
Query OK, 0 rows affected (0.032 sec)obclient [tpcc]>
obclient [tpcc]>
obclient [tpcc]> show create table bmsql_item;
+------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table      | Create Table                                                                                                                                                                                                                                                                                                                                                                                                                           |
+------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| bmsql_item | CREATE TABLE `bmsql_item` (`i_id` int(11) NOT NULL,`i_name` varchar(24) DEFAULT NULL,`i_price` decimal(5,2) DEFAULT NULL,`i_data` varchar(50) DEFAULT NULL,`i_im_id` int(11) DEFAULT NULL,KEY `index_id` (`i_id`) BLOCK_SIZE 16384 LOCAL
) DEFAULT CHARSET = utf8mb4 ROW_FORMAT = DYNAMIC COMPRESSION = 'zstd_1.3.8' REPLICA_NUM = 1 BLOCK_SIZE = 16384 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 0 |
+------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.020 sec)

注意

单独删除表中索引时 ，索引不会进入回收站

obclient [ceshi]> drop index index_id on bmsql_item;
Query OK, 0 rows affected (0.243 sec)obclient [ceshi]>
obclient [ceshi]>
obclient [ceshi]>
obclient [ceshi]> SHOW RECYCLEBIN;
Empty set (0.006 sec)obclient [ceshi]>

恢复表并重命名
obclient [tpcc]> drop table bmsql_item;
Query OK, 0 rows affected (0.046 sec)obclient [tpcc]>
obclient [tpcc]>
obclient [tpcc]>
obclient [tpcc]> SHOW RECYCLEBIN;
+-----------------------------------------+-----------------------+-------+----------------------------+
| OBJECT_NAME                             | ORIGINAL_NAME         | TYPE  | CREATETIME                 |
+-----------------------------------------+-----------------------+-------+----------------------------+
| __recycle_$_1715845727_1715926394294472 | __idx_500011_index_id | INDEX | 2024-05-17 14:13:14.294342 |
| __recycle_$_1715845727_1715926394302672 | bmsql_item            | TABLE | 2024-05-17 14:13:14.301867 |
+-----------------------------------------+-----------------------+-------+----------------------------+
2 rows in set (0.006 sec)obclient [tpcc]>
obclient [tpcc]>
obclient [tpcc]> FLASHBACK TABLE __recycle_$_1715845727_1715926394302672 TO BEFORE DROP RENAME To bmsql_test;
Query OK, 0 rows affected (0.040 sec)obclient [tpcc]>
obclient [tpcc]> show create table bmsql_test;
+------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table      | Create Table                                                                                                                                                                                                                                                                                                                                                                                                                           |
+------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| bmsql_test | CREATE TABLE `bmsql_test` (`i_id` int(11) NOT NULL,`i_name` varchar(24) DEFAULT NULL,`i_price` decimal(5,2) DEFAULT NULL,`i_data` varchar(50) DEFAULT NULL,`i_im_id` int(11) DEFAULT NULL,KEY `index_id` (`i_id`) BLOCK_SIZE 16384 LOCAL
) DEFAULT CHARSET = utf8mb4 ROW_FORMAT = DYNAMIC COMPRESSION = 'zstd_1.3.8' REPLICA_NUM = 1 BLOCK_SIZE = 16384 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 0 |
+------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.028 sec)

恢复表到指定的数据库并重命名

还原表时，默认将表 还原至 删除之前所在的 database 或者 schema 中

obclient [tpcc]> drop table bmsql_test;
Query OK, 0 rows affected (0.039 sec)obclient [tpcc]>
obclient [tpcc]>
obclient [tpcc]>
obclient [tpcc]> SHOW RECYCLEBIN;
+-----------------------------------------+-----------------------+-------+----------------------------+
| OBJECT_NAME                             | ORIGINAL_NAME         | TYPE  | CREATETIME                 |
+-----------------------------------------+-----------------------+-------+----------------------------+
| __recycle_$_1715845727_1715926738118152 | __idx_500011_index_id | INDEX | 2024-05-17 14:18:58.117600 |
| __recycle_$_1715845727_1715926738124128 | bmsql_test            | TABLE | 2024-05-17 14:18:58.123400 |
+-----------------------------------------+-----------------------+-------+----------------------------+
2 rows in set (0.006 sec)obclient [tpcc]>
obclient [tpcc]>
obclient [tpcc]> show databases;
+--------------------+
| Database           |
+--------------------+
| ceshi              |
| information_schema |
| mysql              |
| oceanbase          |
| tpcc               |
+--------------------+
5 rows in set (0.006 sec)obclient [tpcc]>
obclient [tpcc]> FLASHBACK TABLE __recycle_$_1715845727_1715926738124128 TO BEFORE DROP RENAME To ceshi.bmsql_item;
Query OK, 0 rows affected (0.036 sec)obclient [tpcc]> use ceshi;
Database changed
obclient [ceshi]>
obclient [ceshi]> show tables;
+-----------------+
| Tables_in_ceshi |
+-----------------+
| bmsql_item      |
+-----------------+
1 row in set (0.004 sec)

总结

1.还原任何对象时，都建议使用 回收站中的名称 还原

2.单独删除索引，索引不会进入回收站。删除表时，表中的索引会随着表 一起进入回收站，而且还原时，索引也会随着表一起还原

3.truncate 表是 OB 4.X.X.X 版本不支持通过回收站还原

obclient [tpcc]> truncate table bmsql_config;
Query OK, 0 rows affected (0.096 sec)obclient [tpcc]>
obclient [tpcc]>
obclient [tpcc]>
obclient [tpcc]> show tables;
+------------------+
| Tables_in_tpcc   |
+------------------+
| bmsql_config     |
| bmsql_customer   |
| bmsql_district   |
| bmsql_history    |
| bmsql_new_order  |
| bmsql_oorder     |
| bmsql_order_line |
| bmsql_stock      |
| bmsql_warehouse  |
+------------------+
9 rows in set (0.004 sec)obclient [tpcc]> SHOW RECYCLEBIN;
+-----------------------------------------+---------------+-------+----------------------------+
| OBJECT_NAME                             | ORIGINAL_NAME | TYPE  | CREATETIME                 |
+-----------------------------------------+---------------+-------+----------------------------+
| __recycle_$_1715845727_1716174434474744 | bmsql_item    | TABLE | 2024-05-20 11:07:14.476023 |
+-----------------------------------------+---------------+-------+----------------------------+
1 row in set (0.005 sec)obclient [tpcc]>

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