升级说明
* 支持 OceanBase 数据库 V4.2.1_CE_BP2 及之前的 V4.x_CE 版本通过有效升级路径在线升级到 OceanBase 数据库 V4.2.2_CE 版本。V4.2.1_CE_BP3 及之后的 BP 版本不再支持升级到 V4.2.2_CE 版本。随着 V4.2.1_CE 和 V4.2.x_CE 版本的并行演进，V4.2.1_CE 的后续 BP 版本也会逐步支持升级到 V4.2.x_CE 后续版本。
* ODP 和 OBServer 升级顺序：建议先升级 OBServer 版本再升级 ODP 版本。
* 升级期间，系统会自动禁用合并和 DDL 操作，升级完成后恢复正常使用。
v4.2.1_CE_BP3
Version information
| **Information** | **Description** |
| ------ | ------ |
| Release date | January 2, 2024 |
| Version | V4.2.1_CE_BP3 |
| Commit number | [8fe69c2](https://github.com/oceanbase/oceanbase/releases/tag/v4.2.1_CE_BP3) |
| OBServer RPM version | oceanbase-ce-4.2.1.3-103000032023122818 |
Enhanced features
* Data compression at the communication protocol layer is supported for OBServer nodes and OceanBase Database Proxy (ODP) to reduce the bandwidth costs in data transmission.
* Global indexes are supported in OBKV.
* The `INSERT ... ON DUPLICATE KEY UPDATE` statement is supported.
* The `max_partition_num` parameter is added to control the maximum number of partitions that can be created or modified in the MySQL mode.
* Statistics information can be copied by using `DBMS_STATS.copy_table_stats`.
* Permission-based filtering is implemented in the result set of the `information_schema.SCHEMATA` table, allowing users to query only schemas for which they have permissions.
* The data synchronization performance is improved for the primary/standby architecture in direct connection mode.
* The system load is reduced in scenarios where SQL statements are throttled using `max_concurrent`.
* The `DATA_PROGRESS` column is added to the `CDB_OB_BACKUP_TASKS` view to show the data backup progress.
Bug fixes and improvements
* [Fixed the issue where ERROR 4016 was returned after executing the `SHOW CREATE TABLE` statement when no length was specified for type inference on the input and output of the `JSON_UNQUOTE` function.](https://github.com/oceanbase/oceanbase/commit/6f79c91e45b69f8bfafc50689ff733862e91a41e)
* [Fixed the issue where an error occurred when importing data using the `LOAD DATA` statement for columns containing JSON or large object (LOB) data exceeding 2 MB.](https://github.com/oceanbase/oceanbase/commit/b8daab6b35e36c34da0938459e29482935ed9e6e)
* [Fixed the issue where an exception occurred when connecting to an OBServer node using a `.NET` driver in Visual Studio for Windows.](https://github.com/oceanbase/oceanbase/commit/ea254ef867fb478bc9a131cf5ccdc3b95a7705fc)
* [Fixed the issue where an exception occurred when querying data using the `ST_Contains` function with spatial index.](https://github.com/oceanbase/oceanbase/commit/d30e5adc3145f3be2fe7bbfa9232567010a91cc7)
* [Fixed the issue where the `SHOW CREATE TABLE` statement would return a `CHARSET_INVALID` error when `character_set_results` was not specified.](https://github.com/oceanbase/oceanbase/commit/f80e9151798c816ecadc0ec225c07c7b539d6b8e)
* [Fixed the issue where the `REPLACE` system function did not correctly handle input parameters of the LOB type, resulting in execution errors.](https://github.com/oceanbase/oceanbase/commit/0423901da6d10c4a26a7406130640e5fffbeb0f9)
* [Fixed the issue where ERROR 4013 was returned when starting the OBServer node due to excessive tenant numbers.](https://github.com/oceanbase/oceanbase/commit/aeaa65f1e5c89404c54f00fd978fce05ce9a8009)
* [Fixed the issue of delayed response to business requests and increased tenant CPU utilization during concurrent SQL execution, particularly when a hash join processing a small amount of data is on the right of the `SUBPLAN FILTER` operator in the execution plan.](https://github.com/oceanbase/oceanbase/commit/e90b359d2621265302bc94932688497b8cca1327)
* [Fixed the issue where a statement may time out if a large number of logs were written in a short period of time in a parallel DML (PDML) scenario.](https://github.com/oceanbase/oceanbase/commit/d93a9b10d59c3d751da43e9d62ed0efb3740ade5)
* [Fixed the issue of tenant memory overload caused by memory bloat within the EncodePivot module in small-specification scenarios.](https://github.com/oceanbase/oceanbase/commit/758147a7e171528514653c062a8e1fd4c27dbb68)
* [Fixed the issue of tenant memory overload caused by memory bloat within the SqlExecutor module in multi-table join queries during data transfer.](https://github.com/oceanbase/oceanbase/commit/b5e009d6c706b8ebc99a6cce9e7e649565cc8977)
* [Fixed the issue where ERROR 4038 was returned when using the `INSERT INTO SELECT` statement for bypass import.](https://github.com/oceanbase/oceanbase/commit/ea87585b71ee65591b22283e954d12fe055b3ba2)
* [Improved the performance of the OBKV insertup API, which can be enhanced by setting `binlog_row_image` to `MINIMAL`.](https://github.com/oceanbase/oceanbase/commit/e41db9ca559553e638dacd1f41caa5bdb30b4d55)
* [Fixed the issue where cluster connection exceptions occurred due to high CPU utilization of background threads in an environment with a large number of tenants.](https://github.com/oceanbase/oceanbase/commit/d670ba79a7e0144eebae2b734db2a8082d38e7ee)
Considerations
Starting from V4.2.1_CE_BP2_HF1, batch rescan is disabled by default for the NESTED-LOOP JOIN (NLJ) and SUBPLAN FILTER (SPF) operators during cluster creation. However, for clusters upgrading from earlier versions, batch rescan is enabled by default. If stability issues are found in batch rescan for the NLJ or SPF operator in an environment with large amounts data, you can disable batch rescan for the operator in the entire cluster by executing the `SET GLOBAL _nlj_batching_enabled = false;` statement. If the performance is not as expected after batch rescan is disabled, you can evaluate whether to enable batch rescan again based on the actual situation.
版本信息
| **项目** | **描述** |
| ------ | ------ |
| 发布日期 | 2024-01-02 |
| 版本号 | V4.2.1_CE_BP3 |
| Commit 号 | [8fe69c2](https://github.com/oceanbase/oceanbase/releases/tag/v4.2.1_CE_BP3) |
| OBServer RPM 版本号 | oceanbase-ce-4.2.1.3-103000032023122818 |
特性增强
* 支持 OBServer 与 obproxy 通信协议层的压缩功能，降低数据传输带宽成本。
* OBKV 支持全局索引的能力。
* 支持 `INSERT ... ON DUPLICATE KEY UPDATE` 语法。
* 新增配置项 `max_partition_num` 用于控制 MySQL 模式下允许创建或者更改的最大分区数。
* 支持通过 `DBMS_STATS.copy_table_stats` 拷贝统计信息。
* 对 `information_schema.schemata` 表的结果集增加权限过滤，用户只能查询权限范围内的 Schema。
* 优化网络直连主备库架构下的数据同步性能。
* 优化通过 `max_concurrent` 对 SQL 进行限流场景下系统的负载。
* `CDB_OB_BACKUP_TASKS` 视图新增 `DATA_PROGRESS` 字段，用于展示数据备份进度。
缺陷修复
* [修复 `JSON_UNQUOTE` 类型推导时没有设置 Length，导致 `SHOW CREATE TABLE` 报错 4016 的问题。](https://github.com/oceanbase/oceanbase/commit/6f79c91e45b69f8bfafc50689ff733862e91a41e)
* [修复 Json 或 Lob 类型数据的列数据超过 2M 时，LOAD DATA 导入报错的问题。](https://github.com/oceanbase/oceanbase/commit/b8daab6b35e36c34da0938459e29482935ed9e6e)
* [修复在 Visual Studio for Windows 下，使用 `.NET` 驱动连接 OBServer 异常的问题。](https://github.com/oceanbase/oceanbase/commit/ea254ef867fb478bc9a131cf5ccdc3b95a7705fc)
* [修复使用 `ST_Contains` 函数时，通过空间索引查询数据异常的问题。](https://github.com/oceanbase/oceanbase/commit/d30e5adc3145f3be2fe7bbfa9232567010a91cc7)
* [修复 `character_set_results` 设置为空的场景下，`SHOW CREATE TABLE` 报错 `CHARSET_INVALID` 的问题。](https://github.com/oceanbase/oceanbase/commit/f80e9151798c816ecadc0ec225c07c7b539d6b8e)
* [修复输入参数为 Lob 类型时，`REPLACE` 系统函数没有正确处理，导致执行时报错的问题。](https://github.com/oceanbase/oceanbase/commit/0423901da6d10c4a26a7406130640e5fffbeb0f9)
* [修复租户数量过多时，可能导致 OBServer 启动时报错 4013 内存不足的问题。](https://github.com/oceanbase/oceanbase/commit/aeaa65f1e5c89404c54f00fd978fce05ce9a8009)
* [修复 SQL 并发执行时，当执行计划中 `SUBPLAN FILTER` 右侧是 Hash Join，且 Hash Join 处理数据量比较小时，可能触发业务请求变慢, 租户 CPU 升高的问题。](https://github.com/oceanbase/oceanbase/commit/e90b359d2621265302bc94932688497b8cca1327)
* [修复 PDML 场景下，短时间内大量日志写入可能导致语句超时的问题。](https://github.com/oceanbase/oceanbase/commit/d93a9b10d59c3d751da43e9d62ed0efb3740ade5)
* [修复小规格场景下，EncodePivot 模块内存膨胀导致租户内存爆的问题。](https://github.com/oceanbase/oceanbase/commit/758147a7e171528514653c062a8e1fd4c27dbb68)
* [修复 Transfer 过程中，多表 Join 查询时，SqlExecutor 模块内存膨胀导致租户内存爆满的问题。](https://github.com/oceanbase/oceanbase/commit/b5e009d6c706b8ebc99a6cce9e7e649565cc8977)
* [修复使用 `INSERT INTO SELECT` 语句进行旁路导入数据时，报错 4038 的问题。](https://github.com/oceanbase/oceanbase/commit/ea87585b71ee65591b22283e954d12fe055b3ba2)
* [修复 OBKV insertup 接口性能问题，支持通过设置 `binlog_row_image` 为 MINIMAL 优化 insertup 接口性能。](https://github.com/oceanbase/oceanbase/commit/e41db9ca559553e638dacd1f41caa5bdb30b4d55)
* [修复大量租户环境下，后台线程占用 CPU 过高，导致集群连接异常的问题。](https://github.com/oceanbase/oceanbase/commit/d670ba79a7e0144eebae2b734db2a8082d38e7ee)
注意事项
从 V4.2.1_CE_BP2_HF1 版本开始，新建集群时，Nested Loop join（NLJ）和 SUBPLAN FILTER（SPF）算子的 BATCH RESCAN 优化默认会被关闭。然而，对于从老版本升级上来的集群，它们会默认保持原来的 BATCH RESCAN 打开的状态。对于存量的环境，如果发现 NLJ/SPF BATCH RESCAN 的稳定性问题，可以通过执行 `SET GLOBAL _nlj_batching_enabled = false;` 命令来关闭该优化，这将在整个集群范围内禁用 NLJ/SPF 的 BATCH RESCAN 优化。如果在关闭优化后性能不符合预期，可以根据具体情况重新评估并选择是否重新开启。
v4.2.1_CE_BP2_HF1
Version information
| **Information** | **Description** |
| ------ | ------ |
| Release date | December 18, 2023 |
| Version | V4.2.1_CE_BP2_HF1 |
| Commit number | [f675233](https://github.com/oceanbase/oceanbase/releases/tag/v4.2.1_CE_BP2_HF1) |
| OBServer RPM version | oceanbase-ce-4.2.1.2-102010022023121415 |
Overview
* This version addressed several customer and internal testing issues to enhance product stability.
* Starting from V4.2.1_CE_BP2_HF1, batch rescan is disabled by default for the NESTED-LOOP JOIN (NLJ) and SUBPLAN FILTER (SPF) operators during cluster creation. However, for clusters upgraded from earlier versions to this version, batch rescan is enabled by default. If stability issues are found in batch rescan for the NLJ or SPF operator in an environment with large amounts data, you can disable batch rescan for the operator in the entire cluster by executing the `SET GLOBAL _nlj_batching_enabled = false;` statement. If the performance is not as expected after batch rescan is disabled, you can evaluate whether to enable batch rescan again based on the actual situation.
Bug fixes
* [Fixed the issue where enabling batch rescan for NLJ operators could cause core dump issues on OBServer nodes when the the execution plan generated for an SQL statement includes NLJ operators with batch rescan enabled, and the right-side subplan of the NLJ operator includes operators with materialization operations such as MERGE GROUP BY.](https://github.com/oceanbase/oceanbase/commit/5b43b36a646c9c1c53e9ab6dac9096c6a534d4d7)
* [Fixed the issue where data in subpartitions was not fully scattered after the `SHARDING` attribute of a subpartitioned table group was set to `ADAPTIVE`.](https://github.com/oceanbase/oceanbase/commit/0192ab95e67e57b86107e615aa9ec86ef4f964dc)
* [Fixed the issue where the behavior of the `JSON_EXTRACT` function was inconsistent with that in MySQL Database.](https://github.com/oceanbase/oceanbase/commit/e28f81ddd395e8dea0ccb76024fb8aae324a593b)
版本信息
| **项目** | **描述** |
| ------ | ------ |
| 发布日期 | 2023-12-18 |
| 版本号 | V4.2.1_CE_BP2_HF1 |
| Commit 号 | [f675233](https://github.com/oceanbase/oceanbase/releases/tag/v4.2.1_CE_BP2_HF1) |
| OBServer RPM 版本号 | oceanbase-ce-4.2.1.2-102010022023121415 |
发版目的
* 解决客户及内部测试遇到的问题，提升版本稳定性。
* 从V4.2.1_CE_BP2_HF1 版本开始，新建集群时，Nested Loop join（NLJ）和 SUBPLAN FILTER（SPF）算子的 BATCH RESCAN 优化默认会被关闭。然而，对于从老版本升级上来的集群，它们会默认保持原来的 BATCH RESCAN 打开的状态。对于存量的环境，如果发现 NLJ/SPF BATCH RESCAN 的稳定性问题，可以通过执行 `SET GLOBAL _nlj_batching_enabled = false;` 命令来关闭该优化，这将在整个集群范围内禁用 NLJ/SPF 的 BATCH RESCAN 优化。如果在关闭优化后性能不符合预期，可以根据具体情况重新评估并选择是否重新开启。
缺陷修复
* [修复在 Nested Loop join 算子开启 BATCH RESCAN 优化后，当 SQL 生成的执行计划里包含开启 BATCH RESCAN 的 NLJ 算子，且 NLJ 算子的右支子计划里包含 MERGE GROUP BY 等包含物化操作的算子时，可能导致 OBServer core 的问题。](https://github.com/oceanbase/oceanbase/commit/5b43b36a646c9c1c53e9ab6dac9096c6a534d4d7)
* [修复二级分区表组设置表组属性 `sharding = 'adaptive'` 时，一级分区下的二级分区数据分布没有被完全打散的问题。](https://github.com/oceanbase/oceanbase/commit/0192ab95e67e57b86107e615aa9ec86ef4f964dc)
* [修复 `JSON_EXTRACT` 函数与 MySQL 数据库行为不一致的问题。](https://github.com/oceanbase/oceanbase/commit/e28f81ddd395e8dea0ccb76024fb8aae324a593b)
v4.2.1_CE_BP2
Version information
| **Information** | **Description** |
| ------ | ------ |
| Release date | December 7, 2023 |
| Version | V4.2.1_CE_BP2 |
| Commit number | [ccdde7d3](https://github.com/oceanbase/oceanbase/releases/tag/v4.2.1_CE_BP2) |
| OBServer RPM version | oceanbase-ce-4.2.1.2-102000042023120514 |
Enhanced features
* The MySQL mode of OceanBase Database now supports paging queries while maintaining the same sorting method for each query.
* A new command `TRANSFER PARTITION` is provided to manually adjust the distribution of partitions. With this command, you can migrate specific partitions to specific log streams to aggregate or scatter partitions.
* OBKV now supports data compression for remote procedure calls (RPCs), reducing network bandwidth usage and user costs.
* This version now allows you to set a threshold for switching the storage method of LOB data from INROW (stored in the primary table by using row storage) to OUTROW (stored in a separate LOB auxiliary table). This enhancement aims to improve the performance of LOB data queries.
Product behavioral changes
* The `backup_data_file_size` parameter, which is related to backup and restore, is changed from a cluster-level parameter to a tenant-level parameter.
* The `tableapi_transport_compress_func` parameter, which is related to TableAPI, is renamed as `kv_transport_compress_func`.
* A new parameter `kv_transport_compress_threshold` is introduced to specify the minimum threshold for compressing OBKV query result sets.
* The value range for adaptive adjustment of the `server_cpu_quota_min` and `server_cpu_quota_max` parameters is increased to meet requirements of larger specifications.
| cpu_count | (0C, 8C) | [8C, 16C) | [16C, 32C) | [32C, +∞) |
|-----------|----------|-----------|------------|-----------|
| server_cpu_quota_min | 1C | 2C | 3C | 4C |
| server_cpu_quota_max | 1C | 2C | 3C | 4C |
Bug fixes
* [Fixed the issue where the disk bandwidth was used up during a major compaction after a large amount of data was deleted. This issue occurred because, for each deleted data row, a macroblock was opened to verify whether the data row exists in the macroblock.](https://github.com/oceanbase/oceanbase/commit/64b5667b533e6b33b8053da38f9a5e4b6c48004b)
* [Fixed the issue where a core dump occurred on an OBServer node due to a concurrency error in an earlier version of the OpenSSL library during concurrent calls to encryption functions.](https://github.com/oceanbase/oceanbase/commit/e34c524d4a7543d381ade505a8adb7a15fd00e7f)
* [Fixed the issue where, during the execution of a transfer task, errors were encountered and LOB data writes were repeatedly retried due to the failure to refresh the location cache.](https://github.com/oceanbase/oceanbase/commit/7e1e3738ed50a899c09c3a0649b3ee4ceade2e41)
* [Fixed the issue where, during the concurrent creation of indexes on tables with many partitions, the concurrent execution of INNER SQL statements internally could result in a livelock, causing the task to be unable to progress.](https://github.com/oceanbase/oceanbase/commit/cd1eea43cd4c69d9769b5b3b4ffd941c225f47ed)
* [Fixed the issue where the period of time consumed in executing UPDATE operations on tables containing LOB data was long.](https://github.com/oceanbase/oceanbase/commit/ac0d44e9ca9d64ceb7aa5319137d49789b0b134c)
* [Fixed the issue where excessive disk space was occupied due to the retention of data snapshots during bypass imports of tables containing LOB data.](https://github.com/oceanbase/oceanbase/commit/213527cfbc3699737aec2a2328e5c1b754e06eed)
* [Fixed the issue where modifying the auto-increment column attribute in a table schema and performing a Truncate operation would result in Error 4016 due to the incorrect updates in internal tables.](https://github.com/oceanbase/oceanbase/commit/542cb51c1996019299f131faeeabb02057193f09)
* [Fixed the issue where data of multiple versions may exist when expired data was deleted based on `MaxVersions` in the HBase mode of OBKV.](https://github.com/oceanbase/oceanbase/commit/a888ec170502c3eac5d84ae91ed34d282e083de2)
* [Fixed the issue of memory leaks within the `SysJobMgr` module that caused Error 4013 due to memory exhaustion in the sys500 tenant during the execution of table-level restore tasks.](https://github.com/oceanbase/oceanbase/commit/8a22c6f0161ebc5d45d0021fffe01b80591329fa)
* [Fixed the issue where the units remained in the WAIT GC state for a long period of time and failed to release after deleting a tenant.](https://github.com/oceanbase/oceanbase/commit/df33c1c3267b6285ec50beae224ee55d9416359d)
* [Fixed the issue where, even after setting IOPS for resource isolation, the number of I/O operations would still exceed the limits in some scenarios.](https://github.com/oceanbase/oceanbase/commit/00f564089fd97aa746106353f1c33024ee58cacd)
* [Fixed the issue where a long period of time was consumed in a major compaction that involved millions of tablets.](https://github.com/oceanbase/oceanbase/commit/f61632eeee5d378df35b54e3d77ad6c9991a1f2e)
* [Optimized the log synchronization and physical restore performance.](https://github.com/oceanbase/oceanbase/commit/fc7670e56388135b2ed52792c9aca11cba8b1544)
* [Optimized the performance of spatial index queries by reducing the number of table access operations and minimizing the performance overhead in spatial relationship calculations.](https://github.com/oceanbase/oceanbase/commit/f9ae386433a59a0a9d2fcb2aeb4f6eb039d8b91a)
Considerations
* Before V4.2.1_CE_BP2, there was a problem with the limitation of PX threads, potentially resulting in high CPU load on OBServer nodes. However, this issue has been resolved in V4.2.1_CE_BP2, and an upgrade is recommended.
* In the current version, there are some instability issues when using the `INSERT INTO SELECT` statement for bypass import, particularly when triggering a data transfer. Therefore, it is not recommended to use the `INSERT INTO SELECT` statement for bypass import.
版本信息
| **项目** | **描述** |
| ------ | ------ |
| 发布日期 | 2023-12-07 |
| 版本号 | V4.2.1_CE_BP2 |
| Commit 号 | [ccdde7d3](https://github.com/oceanbase/oceanbase/releases/tag/v4.2.1_CE_BP2) |
| OBServer RPM 版本号 | oceanbase-ce-4.2.1.2-102000042023120514 |
特性增强
* MySQL Mode 支持分页查询保序。
* 新增 `TRANSFER PARTITION` 命令用于手动调整分区分布的能力。通过该命令，用户可以选择将特定的分区迁移到特定的日志流上，从而实现不同分区的聚合或打散分布。
* OBKV 支持 RPC 数据压缩，减小网络带宽占用，降低用户成本。
* 支持设置 LOB 数据存储方式由 INROW （和主表行存储在一起）转换为 OUTROW（将 LOB 数据存储在 LOB 辅助表中）的阈值，优化了大对象场景下的性能。
产品行为变更
* 备份恢复相关配置项 `backup_data_file_size` 由集群级调整为租户级。
* tableAPI 相关配置项 `tableapi_transport_compress_func` 更名为 `kv_transport_compress_func`。
* 新增配置项 `kv_transport_compress_threshold` 用于指定需要进行压缩的 OBKV 查询结果集大小的最小阈值。
* 配置项 `server_cpu_quota_min` 和 `server_cpu_quota_max` 增大自适应变更的范围，以满足更大规格的需求。
| cpu_count | (0c, 8c) | [8c, 16c) | [16c, 32c) | [32c, +∞) |
|-----------|----------|-----------|------------|-----------|
| server_cpu_quota_min | 1c | 2c | 3c | 4c |
| server_cpu_quota_max | 1c | 2c | 3c | 4c |
缺陷修复
* [修复在大量删除数据后做合并操作时，由于每行删除的数据都会打开对应宏块，判断是否存在于宏块中，导致磁盘带宽打爆的问题。](https://github.com/oceanbase/oceanbase/commit/64b5667b533e6b33b8053da38f9a5e4b6c48004b)
* [修复并发调用加密函数时，由于低版本 OpenSSL 库存在并发问题，可能导致 OBServer Core 的问题。](https://github.com/oceanbase/oceanbase/commit/e34c524d4a7543d381ade505a8adb7a15fd00e7f)
* [修复 Transfer 任务执行期间，在写入LOB 数据场景下，由于 Location Cache 没有刷新，导致写入一直重试并报错的问题。](https://github.com/oceanbase/oceanbase/commit/7e1e3738ed50a899c09c3a0649b3ee4ceade2e41)
* [修复对分区数较多的表大量并发建索引时，内部发起的 INNER SQL 并发执行可能形成活锁，导致无法推进任务的问题。](https://github.com/oceanbase/oceanbase/commit/cd1eea43cd4c69d9769b5b3b4ffd941c225f47ed)
* [修复对包含 LOB 类型数据的表执行 Update 操作耗时高的问题。](https://github.com/oceanbase/oceanbase/commit/ac0d44e9ca9d64ceb7aa5319137d49789b0b134c)
* [修复旁路导入包含 LOB 数据时，保留了数据快照，导致磁盘空间占用过多的问题。](https://github.com/oceanbase/oceanbase/commit/213527cfbc3699737aec2a2328e5c1b754e06eed)
* [修复表结构进行自增列属性变更且执行 Truncate 操作后，由于内部表没有正确更新，可能导致表操作报错 4016 的问题。](https://github.com/oceanbase/oceanbase/commit/542cb51c1996019299f131faeeabb02057193f09)
* [修复 OBKV HBase 模式基于 `MaxVersions` 进行过期删除时，可能存在多版本数据的问题。](https://github.com/oceanbase/oceanbase/commit/a888ec170502c3eac5d84ae91ed34d282e083de2)
* [修复执行表级恢复任务时，`SysJobMgr` 模块内存泄漏导致 500 租户内存耗尽报错 4013 的问题。](https://github.com/oceanbase/oceanbase/commit/8a22c6f0161ebc5d45d0021fffe01b80591329fa)
* [修复删除租户后，Unit 长时间不释放，状态卡在 WAIT GC 的问题。](https://github.com/oceanbase/oceanbase/commit/df33c1c3267b6285ec50beae224ee55d9416359d)
* [修复设置 IOPS 资源隔离后，部分场景下 IO 仍会超出限制的问题。](https://github.com/oceanbase/oceanbase/commit/00f564089fd97aa746106353f1c33024ee58cacd)
* [优化百万 Tablet 场景下，合并耗时高的问题。](https://github.com/oceanbase/oceanbase/commit/f61632eeee5d378df35b54e3d77ad6c9991a1f2e)
* [优化日志同步以及物理恢复性能。](https://github.com/oceanbase/oceanbase/commit/fc7670e56388135b2ed52792c9aca11cba8b1544)
* [优化空间索引查询性能，减少回表次数并降低空间关系计算的性能开销。](https://github.com/oceanbase/oceanbase/commit/f9ae386433a59a0a9d2fcb2aeb4f6eb039d8b91a)
注意事项
* V4.2.1_CE_BP2 之前版本，存在 PX 线程限制失效问题，可能会导致 OBServer 的 CPU 负载过高，该问题在 V4.2.1_CE_BP2 已修复，并推荐进行升级。
* 当前版本使用 `INSERT INTO SELECT` 语句旁路导入数据时，如果触发 Transfer，会存在一些不稳定的问题，因此不推荐通过此方法进行旁路导入。
v4.2.1_CE_BP1_HF1
Version information
| **Information** | **Description** |
| ------ | ------ |
| Release date | November 13, 2023 |
| Version | V4.2.1_CE_BP1_HF1 |
| Commit number | [2f6924c](https://github.com/oceanbase/oceanbase/commit/2f6924cd5a576f09d6e7f212fac83f1a15ff531a) |
| OBServer RPM version | oceanbase-ce-4.2.1.1-101010012023111012 |
Overview
This version addressed several customer and internal testing issues to enhance product stability.
Bug fixes and improvements
* [Added a hidden parameter to maintain the same sorting method for each query when paging queries were performed. This feature is compatible with MySQL Database.](https://github.com/oceanbase/oceanbase/commit/2f6924cd5a576f09d6e7f212fac83f1a15ff531a)
* [Fixed the issue where a TTL task occupied too much memory when the OBKV was scanning expired data.](https://github.com/oceanbase/oceanbase/commit/123c042449e27ab09c203c07d1993deefb439c16)
* [Fixed the issue where the original leader of the log stream failed to release the memory occupied by the OBKV TTL task after the log stream switched to a new leader.](https://github.com/oceanbase/oceanbase/commit/b2f0de7253e06362ff4fa307b19dde0867277606)
* [Fixed the memory leak issue in the CreateContext module that might be caused by frequent creation of new connections during the transmission of large objects and text data.](https://github.com/oceanbase/oceanbase/commit/cff2efe3cda625b7975185c945b760f316e29f4e)
* [Fixed the issue where excessive logs were printed when there was a change in tenant roles.](https://github.com/oceanbase/oceanbase/commit/5c6b8e668b17fc70c0fd1eefd062a049d79be500)
版本信息
| **项目** | **描述** |
| ------ | ------ |
| 发布日期 | 2023-11-13 |
| 版本号 | V4.2.1_CE_BP1_HF1 |
| Commit 号 | [2f6924c](https://github.com/oceanbase/oceanbase/commit/2f6924cd5a576f09d6e7f212fac83f1a15ff531a) |
| OBServer RPM 版本号 | oceanbase-ce-4.2.1.1-101010012023111012 |
发版目的
解决客户及内部测试遇到的问题，提升版本稳定性。
缺陷修复
* [新增隐藏配置项，以支持与 MySQL 数据库兼容的分页查询保序功能。](https://github.com/oceanbase/oceanbase/commit/2f6924cd5a576f09d6e7f212fac83f1a15ff531a)
* [修复 OBKV 扫描过期数据时，TTL 任务占用过多内存的问题。](https://github.com/oceanbase/oceanbase/commit/123c042449e27ab09c203c07d1993deefb439c16)
* [修复 LS 切主后，原 LS Leader 持有的 OBKV TTL 任务没有释放占用内存的问题。](https://github.com/oceanbase/oceanbase/commit/b2f0de7253e06362ff4fa307b19dde0867277606)
* [修复在传输大对象和文本类型数据时，频繁创建新连接可能导致的 CreateContext 模块内存泄漏问题。](https://github.com/oceanbase/oceanbase/commit/cff2efe3cda625b7975185c945b760f316e29f4e)
* [修复租户角色变更时日志打印过多问题。](https://github.com/oceanbase/oceanbase/commit/5c6b8e668b17fc70c0fd1eefd062a049d79be500)
v4.2.1_CE_BP1
Version information
| **Information** | **Description** |
| ------ | ------ |
| Release date | November 1, 2023 |
| Version | V4.2.1_CE_BP1 |
| Commit number | [7cb0fb4](https://github.com/oceanbase/oceanbase/commit/7cb0fb494fce3962ae3f067991d6581c96bc0a9e) |
| OBServer RPM version | oceanbase-ce-4.2.1.1-101000062023110109 |
Overview
* This version improved the compatibility of user-defined variables with MySQL Database.
* This version added two views `GV$OB_KV_CONNECTIONS` and `V$OB_KV_CONNECTIONS` to query all active connections of the current tenant in an OBKV database.
* The maximum length of the system variable `ob_tcp_invited_nodes` was changed to 64 KB.
* The default value of the `ls_gc_delay_time` parameter was changed to `0`.
* This version addressed several customer and internal testing issues to enhance product stability.
Bug fixes
* [Fixed the issue where Error 5150 was constantly reported because the tablet location cache of the auto-increment column was not refreshed after the number of units was adjusted for scaling.](https://github.com/oceanbase/oceanbase/commit/f257fc0155820b9d2ca43dd1a9028e9cf606e32f)
* [Fixed the issue in V4.x_CE where a 50 ms timeout limit was set when obtaining GTS snapshot versions, causing failure to successfully obtain Global Timestamp Service (GTS) snapshot versions in high-latency networks and continuous error `OB_GTS_NOT_READY`.](https://github.com/oceanbase/oceanbase/commit/532e24bc0cfa443a38845f35c94ede8744fbdaa1)
* [Fixed the issue where using the HBaseAPI of the OBKV client for batch PUT operations could potentially cause OBServer node crashes.](https://github.com/oceanbase/oceanbase/commit/4a8d26d6a396ce8fa05849baa2cc74dd3cf7fdf8)
* [Fixed the issue where performing InsertOrUpdate operations on the OBKV client with a column specified as the time-to-live (TTL) column using `CURRENT_TIMESTAMP` could cause OBServer node crashes.](https://github.com/oceanbase/oceanbase/commit/030f2ef8ac8cf625f006f78a607b92f51cfd4bd6)
* [Fixed the issue where a core dump might be triggered when the SUBPLAN FILTER (SPF) operator is used for batch rescan. A parameter was added to disable this feature by default.](https://github.com/oceanbase/oceanbase/commit/3ce0b3a0bbeaa5c5fcb541dd650031494e515b1a)
* [Fixed the issue where SQL statements in user-defined functions (UDFs) failed to hit the plan cache when `tx_read_only` is set to `True`.](https://github.com/oceanbase/oceanbase/commit/8d4a0a5099ffb8e11490cdb5f1c28e9cf5b37ed8)
* [Fixed the issue where Error 4002 was reported in PS mode when the default value NULL of a complex data type is used as an input parameter of a stored procedure.](https://github.com/oceanbase/oceanbase/commit/78633e0ef9be82a12cfe355c301183d1ab9126c3)
* [Fixed the issue where some parallel DML (PDML) features might not take effect in multi-table joins.](https://github.com/oceanbase/oceanbase/commit/7998110914d55e92905fbffa0f4bb0a7bb421562)
* [Fixed the issue where memory leak ocurred in the TenantTTLMgr module after TTL tasks were executed in the HBase storage model.](https://github.com/oceanbase/oceanbase/commit/b50022a3551c2712f2db7e5eb6d8bf9453c73875)
* [Fixed the potential issue of data and load imbalance after importing data into non-partitioned tables during parallel table creation.](https://github.com/oceanbase/oceanbase/commit/b8bf17db2651747c1cef16bc38769fd668ffded9)
版本信息
| **项目** | **描述** |
| ------ | ------ |
| 发布日期 | 2023-11-01 |
| 版本号 | V4.2.1_CE_BP1 |
| Commit 号 | [7cb0fb4](https://github.com/oceanbase/oceanbase/commit/7cb0fb494fce3962ae3f067991d6581c96bc0a9e) |
| OBServer RPM 版本号 | oceanbase-ce-4.2.1.1-101000062023110109 |
发版目的
* 提升用户自定义变量与 MySQL 数据库的兼容性。
* OBKV 新增视图 `GV$OB_KV_CONNECTIONS`、`V$OB_KV_CONNECTIONS` 用于查看本租户所有的 KV 活跃连接。
* 系统变量 `ob_tcp_invited_nodes` 长度限制调整为 64K。
* 配置项 `ls_gc_delay_time` 默认值调整为 0。
* 解决客户及内部测试遇到的问题，提升版本稳定性。
缺陷修复
* [修复调整 Unit Number 进行扩缩容后，自增列的 Tablet location cache 没有刷新，导致持续报错 5150 的问题。](https://github.com/oceanbase/oceanbase/commit/f257fc0155820b9d2ca43dd1a9028e9cf606e32f)
* [修复 4.x_CE 版本在获取 GTS 快照版本时设置了 50ms 的超时限制，导致在高延迟网络下无法成功获取 GTS 快照版本，查询持续报错 `OB_GTS_NOT_READY` 的问题。](https://github.com/oceanbase/oceanbase/commit/532e24bc0cfa443a38845f35c94ede8744fbdaa1)
* [修复使用 OBKV 客户端的 HBaseAPI 进行批量 PUT 操作时，可能导致节点宕机的问题。](https://github.com/oceanbase/oceanbase/commit/4a8d26d6a396ce8fa05849baa2cc74dd3cf7fdf8)
* [修复 OBKV 指定带 `CURRENT_TIMESTAMP` 的列作为 TTL 过期列时，使用 OBKV 客户端执行 InsertOrUpdate 操作导致节点宕机的问题。](https://github.com/oceanbase/oceanbase/commit/030f2ef8ac8cf625f006f78a607b92f51cfd4bd6)
* [修复 SPF 算子进行 Batch Rescan 场景下可能触发的 Core 问题，新增开关默认关闭该功能。](https://github.com/oceanbase/oceanbase/commit/3ce0b3a0bbeaa5c5fcb541dd650031494e515b1a)
* [修复 `tx_read_only` 设置为 True 的情况下，UDF 内部 SQL 无法命中 Plan Cache 的问题。](https://github.com/oceanbase/oceanbase/commit/8d4a0a5099ffb8e11490cdb5f1c28e9cf5b37ed8)
* [修复 PS 模式下，复杂类型作为存储过程入参且默认值为 NULL 时，使用默认值报错 4002 的问题。](https://github.com/oceanbase/oceanbase/commit/78633e0ef9be82a12cfe355c301183d1ab9126c3)
* [修复多表关联场景下，部分 PDML 功能可能不生效的问题。](https://github.com/oceanbase/oceanbase/commit/7998110914d55e92905fbffa0f4bb0a7bb421562)
* [修复 Hbase 存储模型执行 TTL 任务后，TenantTTLMgr 模块内存泄漏问题。](https://github.com/oceanbase/oceanbase/commit/b50022a3551c2712f2db7e5eb6d8bf9453c73875)
* [修复非分区表并行建表导入数据后，可能存在数据和负载不均衡的问题。](https://github.com/oceanbase/oceanbase/commit/b8bf17db2651747c1cef16bc38769fd668ffded9)
v4.1.0_CE_BP4_HF1
Version information
| **Information** | **Description** |
| ------ | ------ |
| Release date | October 8, 2023 |
| Version | V4.1.0_CE_BP4_HF1 |
| Commit number | [c8a22da](https://github.com/oceanbase/oceanbase/commit/c8a22dad9e5992353ca80f62d4027a085d952983) |
| OBServer RPM version | oceanbase-ce-4.1.0.2-104010012023100710 |
Overview
This version addressed several customer and internal testing issues to enhance product stability.
Bug fixes
[Fixed the issue where the query results might be incorrect when the query plan included the `EXCHANGE OUT DISTR (PKEY)` field. This issue occurred when parallel JOIN operations were performed on partitioned tables during the upgrade where multiple versions were running at the same time.](https://github.com/oceanbase/oceanbase/commit/c8a22dad9e5992353ca80f62d4027a085d952983)
版本信息
| **项目** | **描述** |
| ------ | ------ |
| 发布日期 | 2023-10-08 |
| 版本号 | V4.1.0_CE_BP4_HF1 |
| Commit 号 | [c8a22da](https://github.com/oceanbase/oceanbase/commit/c8a22dad9e5992353ca80f62d4027a085d952983) |
| OBServer RPM 版本号 | oceanbase-ce-4.1.0.2-104010012023100710 |
发版目的
解决客户及内部测试遇到的问题，提升版本稳定性。
缺陷修复
[修复在升级期间（不同版本同时运行），对分区表并行执行 JOIN 操作的场景下，当查询计划中包含 `EXCHANGE OUT DISTR (PKEY)` 时，查询结果可能不正确的问题。](https://github.com/oceanbase/oceanbase/commit/c8a22dad9e5992353ca80f62d4027a085d952983)
v4.2.1_CE
Version information
| **Information** | **Description** |
| ------ | ------ |
| Release date | October 13, 2023 |
| Version | V4.2.1_CE |
| Commit number | [7b0f436](https://github.com/oceanbase/oceanbase/commit/7b0f43693565654bb1d7343f728bc2013dfff959) |
| OBServer RPM version | oceanbase-ce-4.2.1.0-100000102023092807 |
Overview
OceanBase Database V4.2.1_CE is the first Long-Term Support (LTS) version of the V4.2.x_CE series. This version comes with a range of MySQL-compatible features, such as the `VALUES` statement and `JSON_TABLE` expression. It also introduced the Workload Repository (WR)-based data collection framework and enhanced end-to-end diagnostic capabilities for commercialization. In addition, this version optimized system resource utilization and supports table-level restore and Tencent Cloud Object Storage (COS). This version is recommended in production environments for regular business operations.
Key features
Compatibility with MySQL
* `VALUES` statement
The `VALUES` statement was introduced in MySQL 8.0.19. It can be used to quickly construct a table of data or as a standalone DML statement with support for `ORDER BY` and `Limit` clauses. It can also be used as a special table in regular DML statements. OceanBase Database V4.2.1_CE is compatible with MySQL Database and supports the `VALUES` statement, making table value construction more convenient and easy to use.
<!-- For more information, see [VALUES](https://www.oceanbase.com/docs/common-oceanbase-database-cn-1000000000221394) -->
* `RENAME COLUMN`
The `RENAME COLUMN` syntax was supported since MySQL 8.0. It allows users to rename columns without changing their definitions, which is more lightweight than the `CHANGE COLUMN` syntax. OceanBase Database is compatible with the `RENAME COLUMN` syntax of MySQL 8.0 since V4.2.1_CE.
<!-- For more information, see [RENAME COLUMN](https://www.oceanbase.com/docs/common-oceanbase-database-cn-1000000000221389). -->
OBKV features
* `JSON_TABLE` expression
JSON is a semi-structured data format where users can extract specific values from the JSON strings based on a path. The `JSON_TABLE` expression allows users to convert semi-structured data into structured data. The earlier versions of OceanBase Database already supported the JSON data type, but the `JSON_TABLE` expression was not implemented under the MySQL mode. To meet the needs of users who want to convert JSON data into structured data for computations, V4.2.1_CE also supports this expression under the MySQL mode.
<!-- For detailed instructions, see [JSON_TABLE](https://www.oceanbase.com/docs/common-oceanbase-database-cn-1000000000222214). -->
* OBKV TTL
Time-to-live (TTL) is a commonly used feature in NoSQL databases, designed to automatically expire data. For example, in businesses that deal with historical data, there is a need to periodically scan the data, determine its expiration time, and delete it accordingly. Many businesses currently rely on the TableAPI of OBKV. To simplify the management of periodic data, OceanBase Database provided the OBKV TTL capability since V4.2.1_CE. Users can define TTL attributes at the table or row level using the `CREATE TABLE` statement so that expired data is not processed during read and write operations in OBKV.
<!-- For more information, see [TTL](https://www.oceanbase.com/docs/common-oceanbase-database-cn-1000000000218144). -->
Performance improvements
* Concurrent execution of `CREATE TABLE`
In the earlier versions of OceanBase Database, DDL requests were executed serially in RootService queues. Starting from OceanBase Database V4.1.0_CE, the concurrent DDL capability was introduced, with support for concurrent execution of `TRUNCATE TABLE`. To address the performance issues related to migrating millions of table structures, V4.2.1_CE now supports concurrent execution of `CREATE TABLE`, providing a performance improvement of tenfold or even more compared with serial execution.
* Improved foreign key check performance
Prior to OceanBase Database V4.2.1_CE, foreign key checks were implemented using nested SQL statements, incurring significant overhead. From V4.2.1_CE, foreign key checks are performed using Database Autonomy Service (DAS) tasks, and batch checks in single-table DML operations is supported. Additionally, with the check result caching strategy, noticeable performance improvements have been achieved in `INSERT` and `UPDATE` scenarios. In a single-node scenario (where the parent table and child table are on the same node), the performance degradation caused by foreign key checks during `INSERT` and `UPDATE` operations on foreign key tables is generally controlled to around 10% compared with tables without foreign keys. In a distributed scenario (where the parent table and child table are on different nodes), the performance degradation is generally controlled to around 30% compared with tables without foreign keys during `INSERT` and `UPDATE` operations.
* Dynamic sampling on MemTables
OceanBase Database V4.2.0_CE introduced the dynamic sampling feature, which samples data during the generation of an execution plan. When the number of rows in the SSTable exceeds that in the MemTable, dynamic sampling is performed on SSTable blocks. When the number of rows in the MemTable exceeds that in the SSTable, dynamic sampling is performed on the MemTable. In V4.2.0_CE, this was achieved through full read of the MemTable, which was relatively inefficient. However, in V4.2.1_CE, direct sampling for the MemTable is implemented, utilizing RANGE partitioning to perform interval reads. This enhancement significantly improves the efficiency of dynamic sampling on the MemTable.
* Parallel read of archived logs
In OceanBase Database V4.1.0_CE, OceanBase Change Data Capture (CDC) can consume archived logs through the CDC service or directly consume logs from the archive destination. In V4.2.0_CE, a network-based standby database reuses the log pulling framework of OceanBase CDC to pull logs from the primary database by using the CDC service. After the CDC service receives a log pulling remote procedure call (RPC) request from OceanBase CDC or a network-based standby database, the service first attempts to read logs from the local disk. If the corresponding logs do not exist in the local disk due to reasons such as log stream garbage collection (GC) or log recycling, and if the tenant has enabled log archiving, the CDC service reads logs from the log archive destination, such as the network file system (NFS) or Alibaba Cloud Object Storage Service (OSS). The log reading performance of the CDC service determines the log consumption speed at the downstream. If the performance of the CDC service in reading archived logs from OSS is poor, the synchronization link or the network-based standby database may lag behind the primary database and may be unable to become synchronized with the primary database. To address this issue, V4.2.1_CE allows the CDC service to consume OSS-archived log files based on the basic capability of parallel consumption of OSS files.
Resource optimization
This version optimized the utilization of system resources in public cloud environments, including user tenant memory, memory of the SYS500 tenant, and operating system memory. For example, for Elastic Compute Service (ECS) instances with specifications of 128 GB or higher, the memory utilization of system resources has been reduced from around 30% to approximately 15%.
High availability enhancement
* Table-level restore
Prior to OceanBase Database V4.2.1_CE, tenant-level data restore was supported. If data within a table was damaged due to a misoperation, users needed to rely on the physical restore feature to restore the tenant to a previous point in time or use the import/export feature for table-level restore. V4.2.1_CE added support for table-level restore, allowing users to specify which backup data to use, which databases or tables to restore, which tenant to operate on, and the desired recovery point in time on the target cluster.
<!-- For more information, see [Table-level restore](https://www.oceanbase.com/docs/common-oceanbase-database-cn-1000000000218375). -->
* Support for COS
OceanBase Database V4.1.0_CE supports OSS as the backup media. OceanBase Database V4.2.1_CE supplements this support by allowing users to back up logs and data to COS and read backup data from COS for data restore.
Security enhancement
**Data integrity protection**: The Security Assessment of Commercial Cryptography Application imposes requirements for confidentiality and integrity protection on stored data in information systems. In the versions earlier than V4.2.1_CE, the transparent encryption feature of OceanBase Database has already supported `AES_ECD` and `SM4_CBC` (which are named in the format of encryption algorithm_encryption mode), providing confidentiality protection for stored data. V4.2.1_CE added support for the GCM mode. In addition to data encryption, the checksum of ciphertext is calculated based on the key, and the ciphertext is checked during decryption to determine whether the ciphertext has been changed, thereby protecting data integrity.
Diagnostic capabilities improvement
* WR-based data collection framework
The ease of use of the database performance diagnostics feature is closely related to the efficiency of system tuning. Oracle Database 10g introduces proactive automatic diagnostic capabilities such as Active Session History (ASH), Automatic Workload Repository (AWR), and Automatic Database Diagnostic Monitor (ADDM), and provides an inside-out (with information collected by internal components) and top-down (based on the database time and other metrics) database optimization and analysis framework. After decades of development, these capabilities have become industry benchmarks. OceanBase Database V4.2.1_CE implements a data collection framework similar to AWR of Oracle Database. The framework collects existing data such as ASH reports, statistics, wait events, and SQL execution details, and periodically persists performance-related views of OceanBase Database. OceanBase Database V4.2.1_CE introduces WR views and supports configuration adjustment and snapshot management by using `DBMS_WORKLOAD_REPOSITORY` packages. The new version also unifies, streamlines, enriches, and enhances SYSSTAT, ASH, and other statistical metrics for higher comprehensiveness and accuracy. The performance diagnostic capabilities will be further enhanced in future OceanBase Database versions.
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* Enhanced ASH feature
The ASH feature was introduced in OceanBase Database V4.0.0_CE. It samples the status of all active sessions in the system at an interval of 1 second and records the information in internal tables. In OceanBase Database V4.2.1_CE, additional sampling points related to transactions, storage, and DAS were added. The ASH data is collected into the WR internal table at a default sampling rate of 10:1 and a collection interval of 1 hour. By analyzing ASH data, you can easily identify issues such as long wait events, slow SQL statements, and resource utilization of active sessions, which helps in performance optimization.
* End-to-end diagnostics feature
OceanBase Database V4.2.0_CE supports visualized end-to-end tracing of SQL requests, and in V4.2.1_CE, the configuration management capability for end-to-end diagnosis is further enhanced. A new view `GV$OB_FLT_TRACE_CONFIG` is added to record the configuration policies for end-to-end diagnostics at different levels. The `GV$OB_PROCESSLIST` view now includes `LEVEL`, `SAMPLE_PERCENTAGE`, and `RECORD_POLICY` columns to display the monitoring level, sampling frequency, and recording/printing policy that are effective for each session. Additionally, the `GV$OB_SQL_AUDIT` view includes a new column `FLT_TRACE_ID` to record the end-to-end trace information, enabling comprehensive SQL tracing. OceanBase Cloud Platform (OCP) will also provide corresponding page functionality to support this feature.
Product behavioral changes
The following table describes the product behavioral changes made in this version.
| **Feature** | **Change description** |
| --- | --- |
| Triggers disabled for the `LOAD DATA` statement | The `LOAD DATA` statement is executed in parallel for fast data import. When parallel execution involves triggers, trigger correctness issues may occur. Therefore, triggers are disabled for the `LOAD DATA` statement in OceanBase Database V4.2.1_CE. |
| Semantic change for `tenant=all` | <ul><li>In the versions earlier than OceanBase Database V4.2.1_CE, the semantics of <code>tenant=all</code> was ambiguous. For example, <code>tenant=all</code> indicates all tenants in system parameter settings, but indicates user tenants in backup and restore settings. </li><li>Since OceanBase Database V4.2.1_CE, the semantics of <code>tenant=all</code> is changed and specifies "to include only all user tenants and to exclude SYS and META tenants". <code>tenant=all_user</code> and <code>tenant=all_meta</code> are added, which respectively indicate all user tenants and all META tenants. After the change, <code>tenant=all</code> and <code>tenant=all_user</code> share the exact same semantics. Therefore, <code>tenant=all</code> will be deprecated in future versions. </li></ul> |
| Refined load balancing control | <ul><li>OceanBase Database V4.2.0_CE introduced the load balancing and transfer capabilities, which are specified by the tenant-level parameter <code>enable_rebalance</code>. However, when the <code>enable_rebalance</code> parameter is disabled, you cannot modify <code>unit_num</code>, <code>primary_zone</code>, and other parameters in O&M commands. </li><li>OceanBase Database V4.2.1_CE introduced the tenant-level parameter <code>enable_transfer</code>, which allows you to disable the transfer feature for a tenant. You can use it with the <code>enable_rebalance</code> parameter to control the load balancing strategy for a tenant. <ul><li><code>enable_rebalance=true</code> and <code>enable_transfer=true</code>: specify to dynamically adjust the number of log streams for a tenant based on the load balancing algorithm and automatically perform leader balancing and partition balancing for the tenant. </li><li><code>enable_rebalance=true</code> and <code>enable_transfer=false</code>: specify not to dynamically adjust the number of log streams or perform transfer but only to perform log stream balancing based on existing log streams. </li><li><code>enable_rebalance=false</code> and <code>enable_transfer</code>: invalid. In this case, no load balancing related O&M commands are allowed. </li></ul></li></ul> |
| Case sensitivity in OceanBase CDC | OceanBase CDC is case insensitive in the versions earlier than V4.2.1_CE. The new version supports case sensitivity. The database and table names are output according to the setting of the <code>lower_case_table_names</code> parameter, whose valid values are `0`, `1`, and `2`. |
| Transport Layer Security (TLS) protocol version for SSL encryption | In the versions earlier than V4.2.1_CE, there were no restrictions on the TLS protocol version for SSL encryption. Therefore, clients can use the TLS protocol of an early version for encrypted communication with databases. However, some scenarios require TLS1.2 and TLS1.3 for higher security. For compatibility with clients of earlier versions, OceanBase Database V4.2.1_CE introduces the <code>sql_protocol_min_tls_version</code> parameter, which allows you to specify the minimum version of the TLS protocol. The default value is compatible with previous versions. |
| Calling a stored procedure with an output parameter without returning a result set | MySQL allows you to call a stored procedure with an output parameter without returning the result set of the output parameter. <ul><li> In the versions earlier than OceanBase Database V4.2.1_CE, a result set of an output parameter is returned, causing the native MySQL driver to report an error. </li><li>In OceanBase Database V4.2.1_CE, after you execute a `CALL` statement by using OBClient, the result set of the output parameter is no longer displayed. </li></ul> |
| zlib compression disabled | In OceanBase Database V4.2.1_CE, you cannot use `zlib` compression for new tables or change the compression algorithm of an existing table to `zlib`. |
View changes
The following table describes the changes to views made in this version.
| **View** | **Change type** | **Description** |
| --- | --- | --- |
| CDB/DBA_WR_CONTROL | New | Stores WR-related configurations. |
| [G]V$OB_TENANT_RUNTIME_INFO | New | Displays the running details of tenants. |
| [G]V$OB_SQL_AUDIT | Modified | The `FLT_TRACE_ID` column is added to record end-to-end trace information. |
Parameter changes
The following table describes the parameter changes made in this version.
| **Parameter** | **Change type** | **Description** |
| --- | --- | --- |
| memory_limit_percentage | Modified | The upper limit of the percentage of available memory for OBServer nodes is changed from 90% to 95%. OBServer nodes are allowed to use a higher percentage of resources in servers with high specifications. |
| sql_protocol_min_tls_version | New | The minimum version of the SSL/TLS protocol used by SSL connections for SQL statements. This is a cluster-level parameter. The default value is `none`, which means there are no restrictions on the TLS version for connections. <main id="notice" type='explain'><h4>Note</h4><p>This parameter controls only the version number of SSL. To enable SSL, you must set the <code>ssl_client_authentication</code> parameter. </p></main> |
| enable_transfer | New | Specifies whether to allow transfer within the tenant. This is a tenant-level parameter. This parameter is invalid when `enable_rebalance` is disabled. The default value is `True`, which indicates that transfer within the tenant is allowed. |
| compaction_dag_cnt_limit | New | The maximum number of directed acyclic graphs (DAGs) in a compaction DAG queue. This parameter is a tenant-level parameter. The default value is `15000`. In scenarios with millions of partitions, you can increase the value of this parameter to speed up compaction, which however increases memory consumption. |
| compaction_schedule_tablet_batch_cnt | New | The maximum number of partitions that can be scheduled in each batch for batch compaction scheduling. This parameter is a tenant-level parameter. The default value is `50000`. In scenarios with millions of partitions, you can increase the value of this parameter to speed up compaction, which however increases CPU consumption and results in longer thread scheduling time. |
| server_cpu_quota_min | Modified | The default value is changed from `1` to `0`, and the value range is changed to [0, 16]. The value `0` indicates that the specifications of the `sys` tenant are adaptive. |
| server_cpu_quota_max | Modified | The default value is changed from `1` to `0`, and the value range is changed to [0, 16]. The value `0` indicates that the specifications of the `sys` tenant are adaptive. |
Recommended versions of tools
The recommended platform tool versions for OceanBase Database V4.2.1_CE are described in the following table:
| Tool | Version |
| --- | --- |