PolarDB for MySQL 到 OceanBase

选择对端数据库：

OceanBase

数据链路

基本功能

功能	说明
Schema Migration	If the target schema does not exist, BladePipe will automatically generate and execute CREATE statements based on the source metadata and the mapping rule.
Full Data Migration	Migrate data by sequentially scanning data in tables and writing it in batches to the target database.
Incremental Data Sync	Sync of common DML like INSERT, UPDATE, DELETE is supported. UPDATE and DELETE for tables without primary keys are not synced by default (manual selection required).
Data Verification and Correction	Verify all existing data. Optionally, you can correct the inconsistent data based on verification results. Scheduled DataTasks are supported. For more information, see Create Verification and Correction DataJob.
Subscription Modification	Add, delete, or modify the subscribed tables with support for historical data migration. For more information, see Modify Subscription.
Position Resetting	Reset positions by file position or timestamp. Allow re-consumption of incremental data logs in a past period or since a specific Binlog file and position.
Table Name Mapping	Support the mapping rules, namely, keeping the name the same as that in Source, converting the text to lowercase, converting the text to uppercase, truncating the name by "_digit" suffix.
DDL Sync	ALTER TABLE ADD COLUMN, DROP COLUMN, MODIFY COLUMN ADD INDEX RENAME TABLE CREATE TABLE (whole database sync)
Metadata Retrieval	Retrieve the target metadata with filtering conditions or target primary keys set from the source table.

高级功能

功能	说明
全量前清空目标数据	运行全量任务前清除老数据，包括重跑任务、定时全量迁移都会触发此能力
重建目标表	运行全量任务前重建目标表，包括重跑任务、定时全量迁移都会触发此能力
高并发行级写入	适配分布式数据库特征，默认采用高并发行级写入策略 (ROW)
增量写入冲突策略	IGNORE: 遇到主键冲突则忽略（不做写入），REPLACE: 遇到主键冲突则整行替换
Online DDL Compatibility	Support GH-OST, PT-OSC, Aliyun DMS Online DDL.
Custom Code	For more information, see Custom Code Processing, Debug Custom Code and Logging in Custom Code.
Adding Virtual Columns	Support adding custom virtual columns with fixed values, such as region, ID, etc.
Setting Target Primary Key	Change the primary key to another field to facilitate data aggregation and other operations.
Data Filtering Conditions	Support data filtering using WHERE conditions, with SQL-92 as the SQL language. For more information, see Data Filtering.

限制和注意点

限制项	说明
OceanBase 版本	当前仅支持 OceanBase for MySQL 版本
OceanBase 数据类型	不支持地理位置类型

使用示例

标题	详情
主流 RDB 到 OceanBase 迁移同步	文档：RDB 到 OceanBase 迁移同步

链路FAQ

• MySQL 任务延迟怎么办?

• MySQL 源端找不到 binlog 文件

• 如何打开 MySQL 源端心跳?

• MySQL 源端 Schema 权限报错怎么办?

  Tips: MySQL 源端相关 FAQ 同样适用于 MySQL 系数据源。

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源端数据源

前置条件

条件	说明
账号权限	云数据库读写账号或高权限账号
开启 Binlog	云数据实例详情 > 配置与管理 > 参数配置 > 设置 loose_polar_log_bin 为 true
PolarDbMySQL 字符集	支持 utf8, utf8mb4, latin1, 其他编码暂未测试

任务参数

参数名称	说明
parseBinlogParallel	增量解析 Binlog 的并发数
parseBinlogBufferSize	用于增量解析 Binlog 的环形队列大小
maxTransactionSize	单事务最大数据条数，超过则分段刷出
limitThroughputMb	限制增量 Binlog 流量
extraDDL	兼容额外的 DDL 同步，包括 PT, GHOST, ALI_DMS, PT_GHOST
needJsonEscape	将 json 中特殊字符进行转义，以写入到对端

Tips: 通用参数配置请参考 通用参数及功能

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目标端数据源

前置条件

条件	说明
账号权限	具备 SELECT, INSERT, DELETE, UPDATE, 常见 DDL 权限
网络准备	迁移同步节点（sidecar）可连接 OceanBase 标准交互接口（如 3306）

任务参数

参数名称	说明
keyConflictStrategy	增量写入遇到主键冲突策略: IGNORE 冲突忽略（默认） REPLACE 冲突替换（可选）
writeStrategy	对端写入策略，包含 ROW (单条，默认选项) MULTI_SQL (多语句) BATCH (批量)

Tips: 通用参数配置请参考 通用参数及功能