MySQL to Dameng

BladePipe supports data replication from MySQL to Dameng. View supported migration, sync, verification, and connector capabilities.

Target DataSource：

Dameng

Connection

Basic Functions

Function	Description
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, MODIFY COLUMN, RENAME COLUMN, DROP COLUMN 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.

Advanced Functions

Function	Description
Clear Target Data Before Full Migration	Clear old data before running the full migration task, triggered by manual reruns or scheduled full migrations.
Rebuild Target Table	Rebuild the target table before running the full migration task, triggered by manual reruns or scheduled full migrations.
Incremental Write Conflict Strategy	IGNORE: Ignore primary key conflicts (no write), REPLACE: Replace the entire row on primary key conflicts.
Zero-Value Time Handling	Support setting zero-value timestamps to different types of values to prevent errors when writing to the target.
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.

Limits

Limit	Description
MySQL Storage Engine	Support InnoDB, MyISAM, AWS XEngine. Other storage engines have not been tested yet.
MySQL Character Set	Support utf8, utf8mb4, latin1. Other encodings have not been tested yet.

FAQ

• How to handle MySQL DataJob latency?

• What to do when binary Log cannot be found in MySQL Source?

• What to do when access to schema in MySQL Source is denied?

  Tip: MySQL source-related FAQ also applies to MySQL-based DataSources.

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Source

Prerequisites

Prerequisite	Description
Permissions for Account	See Permissions Required for MySQL/MariaDB.
Enabling Binlog	[mysqld] log-bin=mysql-bin # Enable Binlog binlog-format=ROW # Choose ROW mode binlog_row_image=FULL # Changes include all column data

Parameters

Parameter	Description
parseBinlogParallel	Number of threads for parallel parsing of Binlog in Incremental DataJobs.
parseBinlogBufferSize	Size of the circular buffer for parsing Binlog in Incremental DataJobs.
maxTransactionSize	Maximum number of data rows per transaction. If exceeded, the transaction will be split and flushed in parts.
limitThroughputMb	Limit the throughput of incremental Binlogs.
extraDDL	Support synchronization of additional DDL, including PT, GHOST, ALI_DMS, and PT_GHOST.
needJsonEscape	Escape special characters in JSON to be written to the target database.
fullDataSqlConditionEnabled	Add filtering conditions in SQL during source data scanning. It only works in Full Data migration.
srcTimeZone	Source time zone, e.g., +08:00, Asia/Shanghai, America/New_York, etc.

Tips: To modify the general parameters, see General Parameters and Functions.

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Target

Prerequisites

Prerequisite	Description
Accounts and Permissions	Documentation: Permissions Required for Dameng
Network Preparation	The sidecar node must be able to connect to the standard interactive interface of Dameng (e.g., 5432).

Parameters

Parameter	Description
keyConflictStrategy	Policy for primary key conflicts during incremental writes: IGNORE Ignore conflicts (default) REPLACE Replace on conflicts (optional)
dstWholeReplace	Convert INSERT and UPDATE operations into full-row replacement on the target.
writeStrategy	Target write strategy, including: ROW (Single row) MULTI_SQL (Multi-statement SQL) BATCH (Batch write, default option)

Tips: To modify the general parameters, see General Parameters and Functions.