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    Data Transmission Service:Migrate from RDS SQL Server to AnalyticDB for MySQL 3.0

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    Data Transmission Service:Migrate from RDS SQL Server to AnalyticDB for MySQL 3.0

    Last Updated:Jul 17, 2026

    Migrate data from SQL Server (including ApsaraDB RDS for SQL Server and self-managed SQL Server) to AnalyticDB for MySQL for real-time data analysis.

    Supported source databases

    The following SQL Server source databases can be migrated to AnalyticDB for MySQL. This topic uses an RDS for SQL Server instance as an example. The process for other sources is similar.

    • RDS for SQL Server instances.

    • Self-managed databases:

      • Self-managed database with a public IP address
      • Self-managed database that is hosted on Elastic Compute Service (ECS)
      • Self-managed database that is connected over Express Connect, VPN Gateway, or Smart Access Gateway
      • Self-managed database that is connected over Database Gateway

    Prerequisites

    • This migration task can be configured only in the new console.

    • A source RDS SQL Server instance has been created. For a list of supported versions, see Overview of migration solutions. To create an instance, see Create an ApsaraDB RDS for SQL Server instance.

      Important

      If the RDS SQL Server instance runs SQL Server 2008 or SQL Server 2008 R2, incremental data migration is not supported.

    • A target AnalyticDB for MySQL cluster has been created. For instructions, see Create a cluster.

    • The storage capacity of the target AnalyticDB for MySQL cluster must be greater than that of the source RDS SQL Server instance.

    • If the source instance meets any of the following conditions, split it into multiple migration tasks.

      • The source instance has more than 10 databases.

      • Log backups are performed more than once per hour for a single database.

      • More than 100 Data Definition Language (DDL) operations are performed per hour on a single database.

      • The log generation rate for a single database exceeds 20 MB/s.

      • You must enable change data capture (CDC) on more than 1,000 tables.

    Notes

    Note

    • During schema migration, DTS does not migrate foreign keys from the source database to the destination database.

    • During full data migration and incremental data migration, DTS temporarily disables constraint checks and foreign key cascading operations at the session level. If cascading update or delete operations occur in the source database while the task is running, data inconsistency may occur.

    • During schema migration, DTS does not support migrating materialized views to the destination AnalyticDB for MySQL instance. To use materialized views, manually create them in the destination instance after migration is complete.

    Type

    Description

    Source database limits

    • The source database server must have sufficient outbound bandwidth. Insufficient bandwidth reduces data migration speed.

    • The tables to be migrated must have a primary key or unique constraint, and the columns in the key or constraint must be unique. Otherwise, data duplication may occur in the destination database.

    • If you select specific tables for migration and need to edit them (for example, map table or column names), a single migration task can migrate a maximum of 1,000 tables. If you exceed this limit, the task fails upon submission. Split the tables into multiple tasks or configure a task to migrate the entire database.

    • A single migration task supports a maximum of 10 databases. Exceeding this limit may cause stability and performance issues. Split the migration into multiple tasks if needed.

    • If you configure a task to migrate specific objects instead of an entire database, you cannot migrate objects that have the same table name but different schema names to the same destination database within a single task.

    • If you perform incremental data migration, the transaction logs must meet the following requirements:

      • Transaction logging must be enabled, the backup mode must be set to Full, and a full physical backup must have been successfully performed.

      • For incremental-only data migration, Data Transmission Service (DTS) requires retaining source database transaction logs for more than 24 hours. If a task includes both full and incremental data migration, retain logs for at least seven days. After full data migration is complete, you can reduce the retention period to more than 24 hours. Otherwise, the DTS task may fail due to unavailable transaction logs. In extreme cases, data inconsistency or loss may occur. Issues caused by insufficient log retention are not covered by the DTS Service Level Agreement (SLA).

    • If you enable CDC (change data capture) for the source tables to be migrated, they must meet the following conditions. Otherwise, the precheck will fail.

      • The value of the srvname field in the sys.sysservers view must be the same as the return value of the SERVERPROPERTY function.

      • If the source database is a self-managed SQL Server, the database owner must be sa. If the source database is an ApsaraDB RDS for SQL Server instance, the database owner must be sqlsa.

      • If the source database is Enterprise Edition, it must be SQL Server 2008 or later.

      • If the source database is Standard Edition, it must be SQL Server 2016 SP1 or later.

      • If the source database is SQL Server 2017 (Standard or Enterprise Edition), upgrade it to a later version.

    • DTS uses the fn_log function to obtain logs from the source database. This function has performance bottlenecks, so do not clear source database logs prematurely. Otherwise, the DTS task may fail.

    • Limits on operations in the source database:

      • During the schema migration and full data migration phases, do not perform DDL operations that change the database or table structure. Otherwise, the data migration task will fail.

      • If you perform only full data migration, do not write new data to the source instance. Otherwise, data in the source and destination databases becomes inconsistent. To ensure real-time data consistency, select Schema Migration, Full Data Migration, and Incremental Data Migration.

    • If the source database is a read-only instance, DTS does not migrate DDL operations.

    • If the source database is an Azure SQL Database, a migration instance can migrate only one database.

    • If the source database is an ApsaraDB RDS for SQL Server instance and the migration task includes incremental data migration, ensure that Transparent Data Encryption (TDE) is disabled for task stability. For more information, see Disable TDE.

    • If you use the sp_rename command to rename objects such as stored procedures before the schema migration task runs, the task may not work as expected or may fail.

      Note

      Use the ALTER command to rename database objects.

    • In hybrid log-based parsing mode, the source database does not support consecutive column add or drop operations with an interval of less than 10 minutes. For example, if you run the following SQL statements consecutively, the task will fail.

      ALTER TABLE test_table DROP COLUMN Flag;
ALTER TABLE test_table ADD Remark nvarchar(50) not null default('');

    • If the source database is an ApsaraDB RDS for SQL Server instance that runs the Web edition, set SQL Server Incremental Synchronization Mode to Incremental Synchronization Based on Logs of Source Database (Heap tables are not supported) when you configure the task.

    • During full data migration, enable the READ_COMMITTED_SNAPSHOT parameter for the source database to prevent shared lock contention from affecting data writes. Otherwise, data inconsistency or task failure may occur. Issues caused by not enabling this parameter are not covered by the DTS SLA.

    Other limits

    • Migration is supported for basic data types only, but not for data of the CURSOR, ROWVERSION, SQL_VARIANT, HIERARCHYID, POLYGON, GEOMETRY, or GEOGRAPHY types, or for user-defined types that are created by using the CREATE TYPE command.

    • If a DDL statement fails to be written to the destination database, the DTS task continues to run. You must check the task logs to find the failed DDL statement. To learn how to view task logs, see View task logs.

    • The destination database must have a custom primary key. Or, in the Configurations for Databases, Tables, and Columns step, set the Primary Key Column. Otherwise, migration may fail.

    • If you set Configure Objects to SQL Server Incremental Synchronization Mode in the Incremental Synchronization Based on Logs of Source Database (Heap tables are not supported) step, the tables to be migrated must have a clustered index that includes the primary key column. DTS does not support migrating heap tables, tables without primary keys, compressed tables, tables with computed columns, or tables with sparse columns in this mode. These limitations do not apply in hybrid log-based parsing mode.

    • If you set Configure Objects to SQL Server Incremental Synchronization Mode in the Log-based Parsing for Non-heap Tables and CDC-based Incremental Synchronization for Heap Tables (Hybrid Log-based Parsing) step, the following limits also apply:

      • DTS relies on the CDC component for incremental migration. Ensure that the CDC job in the source database is running as expected. Otherwise, the DTS task will fail.

      • By default, the CDC component stores incremental data for three days. Adjust the retention period by running the exec console.sys.sp_cdc_change_job @job_type = 'cleanup', @retention= <time>; command.

        Note

        • <time> specifies the retention period in minutes.

        • If the average number of daily incremental SQL changes for a single table exceeds 10 million, set <time> to 1440.

      • In a single migration task, enable CDC for no more than 1,000 tables. Otherwise, the task may experience high latency or become unstable.

      • The precheck module for a DTS incremental data migration task enables CDC in the source database. During this process, the SQL Server engine's internal limitations may cause temporary table locking in the source database.

    • If you set Configure Objects to SQL Server Incremental Synchronization Mode in the Polling and querying CDC instances for incremental synchronization step, the following limits also apply:

      • The source database account used by the DTS instance must have the permissions to enable CDC. An account with the sysadmin role is required to enable database-level CDC. A privileged account is required to enable table-level CDC.

        Note

        • The most privileged account (server administrator) provided by the Azure SQL Database console meets the requirements. For databases purchased based on the vCore model, CDC can be enabled for all specifications. For databases purchased based on the DTU model, CDC can be enabled only for service tiers of S3 or higher.

        • The privileged account of an Amazon RDS for SQL Server instance meets the requirements and supports enabling database-level CDC via stored procedures.

        • CDC cannot be enabled for tables that have a clustered columnstore index.

        • The precheck module for a DTS incremental data migration task enables CDC in the source database. During this process, the SQL Server engine's internal limitations may cause temporary table locking in the source database.

      • DTS obtains incremental data by polling and querying the CDC instance of each table in the source database. Migrate no more than 1,000 tables from the source database. Otherwise, the task may experience high latency or become unstable.

      • By default, the CDC component stores incremental data for three days. Adjust the retention period by running the exec console.sys.sp_cdc_change_job @job_type = 'cleanup', @retention= <time>; command.

        Note

        • <time> specifies the retention period in minutes.

        • If the average number of daily incremental SQL changes for a single table exceeds 10 million, set <time> to 1440.

      • Consecutive column add or drop operations are not supported (more than two ADD COLUMN or DROP COLUMN DDL operations within one minute). Otherwise, the task may fail.

      • Do not modify the CDC instances of the source database. Otherwise, the data migration task may fail or data loss may occur.

    • To ensure accurate latency reporting for incremental data migration, DTS creates objects in the source database. In the log-based parsing mode, DTS creates a dts_cdc_sync_ddl trigger, a dts_sync_progress heartbeat table, and a dts_cdc_ddl_history DDL storage table. In the hybrid log-based parsing mode, DTS creates the same objects and also enables database-level and table-level CDC. For tables where CDC is enabled, the rate of data changes should not exceed 1,000 rows per second (RPS).

    • Due to inherent limits of AnalyticDB for MySQL, write performance to the destination database slows down when node disk usage of the AnalyticDB for MySQL exceeds 80%, causing DTS task delays. If disk usage exceeds 90%, writes fail entirely and the DTS task fails. Estimate the required disk space based on the migration objects and ensure sufficient storage in the destination cluster.

    • If the destination AnalyticDB for MySQL 3.0 cluster is backing up while the DTS task runs, the task fails.

    • Before migrating data, evaluate the performance of the source and destination databases and perform migration during off-peak hours. During full data migration, DTS consumes read and write resources on both databases, which may increase their load.

    • During full data migration, concurrent INSERT operations can cause fragmentation in the destination tables, so table storage space in the destination database may be larger than in the source database after migration.

    • Verify that the precision DTS uses to migrate columns of the FLOAT or DOUBLE data type meets your business requirements. DTS uses the ROUND(COLUMN,PRECISION) function to read values from these columns. If a precision is not explicitly defined, DTS migrates FLOAT values with a precision of 38 digits and DOUBLE values with a precision of 308 digits.

    • DTS attempts to resume a failed task for up to seven days. Before switching your business workloads to the destination instance, end or release the migration task. Alternatively, revoke the write permissions of the DTS account on the destination instance by using the revoke command to prevent a resumed task from overwriting destination data.

    • If a migration task includes incremental data migration, you cannot perform re-indexing operations. This may cause the task to fail or result in data loss.

      Note

      You cannot modify the primary key of a table for which CDC is enabled.

    • If the number of CDC-enabled tables in a single migration task exceeds the value set in the The maximum number of tables for which CDC is enabled that DTS supports. parameter, the precheck fails.

    • If a task includes incremental migration and a single field in a CDC-enabled table to be written contains more than 64 KB of data, run the exec sp_configure 'max text repl size', -1; command to adjust the source database configuration in advance.

      Note

      By default, a CDC job can process a maximum data size of 64 KB for a single field.

    • When multiple migration instances use the same source SQL Server database, their incremental data collection modules operate independently.

    • If a task fails, DTS support staff will attempt to restore it within eight hours. During restoration, they may restart the task or adjust its parameters.

      Note

      Only DTS task parameters are modified—not database parameters. Parameters that may be adjusted include those listed in Modify instance parameters.

    • SQL Server is a commercial, closed-source database whose log format can cause unavoidable issues during incremental CDC and parsing in DTS. Before enabling DTS for incremental synchronization from a SQL Server source in a production environment, perform comprehensive proof-of-concept (POC) testing that covers all business change scenarios, schema adjustments, and peak-load stress tests. Consistency between your production environment logic and the POC phase is essential for stable DTS operations.

    • When the destination database is AnalyticDB for MySQL, DTS supports writing only the data types that are natively supported by AnalyticDB for MySQL, including basic data types and complex data types such as ARRAY, MAP, and JSON. Other types such as MULTIVALUE are not supported.

    • Partial transaction rollbacks on the source database are not supported during incremental migration and may be lost.

    Special cases

    If the source is an ApsaraDB RDS for SQL Server instance, DTS creates a system account named rdsdt_dtsacct on the instance for data migration. Do not delete this account or change its password while the task is running. Otherwise, the task may fail. For more information, see System accounts.

    Billing

    Migration type

    Instance configuration fee

    Internet traffic fee

    Schema migration and full data migration

    Free of charge.

    When the Access Method parameter of the destination database is set to Public IP Address, you are charged for Internet traffic. For more information, see Billing overview.

    Incremental data migration

    Charged. For more information, see Billing overview.

    Migration types

    • Schema migration

      DTS migrates the schema definitions of the migration objects from the source database to the destination database.

      • DTS can migrate the following schema objects: schemas, tables, views, functions, and procedures.

      • DTS cannot migrate the following objects: assemblies, service brokers, full-text indexes, full-text catalogs, distributed schemas, distributed functions, Common Language Runtime (CLR) stored procedures, CLR scalar-valued functions, CLR table-valued functions, internal tables, systems, or aggregate functions.

      Warning

      In heterogeneous database migrations, data types may not map one-to-one, potentially causing task failures or data loss. Evaluate the business impact of data type mappings before proceeding. For more information, see Data type mapping for heterogeneous databases.

    • Full migration

      DTS migrates all historical data of the specified migration objects from the source database to the destination database.

    • Incremental migration

      After a full migration is complete, DTS migrates incremental data updates from the source database to the destination database. Incremental migration lets you smoothly migrate data without interrupting your self-managed applications.

    Supported SQL operations for incremental migration

    Operation type

    SQL statement

    DML

    INSERT, UPDATE, and DELETE

    Note

    • Incremental migration does not support UPDATE statements that modify only large fields.

    • When you write data to AnalyticDB for MySQL, it automatically converts UPDATE statements to REPLACE INTO. If you update a primary key, it converts the UPDATE statement to a DELETE followed by an INSERT.

    DDL

    • CREATE TABLE

    • ALTER TABLE

      Only ADD COLUMN and DROP COLUMN are supported.

    • DROP TABLE

    • CREATE INDEX and DROP INDEX

    Note

    • DDL operations that contain a user-defined type are not supported.

    • Transactional DDL operations are not supported. For example, a single SQL statement that adds multiple columns or contains both DDL and DML operations may cause data loss.

    • Online DDL operations are not supported.

    • DDL operations that use a reserved keyword as an attribute name are not supported.

    • DDL operations performed by a system stored procedure are not supported.

    • DTS does not support TRUNCATE TABLE operations.

    • Tables with partitions or definitions containing a function are not supported.

    Database account permissions

    Database

    Schema migration

    Full data migration

    Incremental data migration

    RDS SQL Server instance

    Read permissions on objects to be migrated

    Read permissions on objects to be migrated

    Owner permissions on objects to be migrated

    AnalyticDB for MySQL cluster

    Read and write permissions

    To create and grant permissions to a database account, see the following topics:

    Procedure

    1. Navigate to the migration task list page for the destination region using one of the following methods.

      From the DTS console

      1. Log on to the Data Transmission Service (DTS) console.

      2. In the navigation pane on the left, click Data Migration.

      3. In the upper-left corner of the page, select the region where the migration instance is located.

      From the DMS console

      Note

      The actual operations may vary based on the mode and layout of the DMS console. For more information, see Simple mode console and Customize the layout and style of the DMS console.

      1. Log on to the Data Management (DMS) console.

      2. In the top menu bar, choose Data + AI > Data Transmission (DTS) > Data Migration.

      3. To the right of Data Migration Tasks, select the region where the migration instance is located.

    2. Click Create Task to navigate to the task configuration page.

    3. Configure the source and destination databases.

      Warning

      After you select the source and destination instances, we recommend that you carefully read the limits displayed at the top of the page. Otherwise, the task may fail or data inconsistency may occur.

      Category

      Parameter

      Description

      N/A

      Task Name

      DTS automatically generates a task name. We recommend that you specify a descriptive name for easy identification. The name does not need to be unique.

      Source Database

      Select Existing Connection

      • To use a database instance that has been added to the system (created or saved), select the desired database instance from the drop-down list. The database information below will be automatically configured.

        Note

        In the DMS console, this parameter is named Select a DMS database instance..

      • If you have not registered the database instance with the system, or do not need to use a registered instance, manually configure the database information below.

      Database Type

      Select SQL Server.

      Access Method

      Select Alibaba Cloud Instance.

      Instance Region

      Select the region where the source RDS SQL Server instance resides.

      Replicate Data Across Alibaba Cloud Accounts

      This example shows how to migrate data within the same Alibaba Cloud account. Select No.

      RDS Instance ID

      Select the ID of the source RDS SQL Server instance.

      Database Account

      Enter the database account for the source RDS SQL Server instance. For details on required permissions, see Permission requirements for database accounts.

      Database Password

      Enter the password for the database account.

      Encryption

      Select Non-encrypted or SSL-encrypted based on your business requirements.

      • If SSL encryption is disabled for the source database, select Non-encrypted.

      • If SSL encryption is enabled for the source database, select SSL-encrypted. By default, DTS trusts the server certificate.

      Destination Database

      Select Existing Connection

      • To use a database instance that has been added to the system (created or saved), select the desired database instance from the drop-down list. The database information below will be automatically configured.

        Note

        In the DMS console, this parameter is named Select a DMS database instance..

      • If you have not registered the database instance with the system, or do not need to use a registered instance, manually configure the database information below.

      Database Type

      Select AnalyticDB for MySQL 3.0.

      Access Method

      Select Alibaba Cloud Instance.

      Instance Region

      Select the region where the destination AnalyticDB for MySQL 3.0 cluster resides.

      Instance ID

      Select the ID of the destination AnalyticDB for MySQL 3.0 cluster.

      Database Account

      Enter the database account for the destination AnalyticDB for MySQL 3.0 cluster. For details on required permissions, see Permission requirements for database accounts.

      Database Password

      Enter the password for the database account.

    4. After you complete the configuration, click Test Connectivity and Proceed at the bottom of the page.

      Note

      • Ensure that the IP address segment of the DTS service is automatically or manually added to the security settings of the source and destination databases to allow access from DTS servers. For more information, see Add DTS server IP addresses to a whitelist.

      • If the source or destination database is a self-managed database (the Access Method is not Alibaba Cloud Instance), you must also click Test Connectivity in the CIDR Blocks of DTS Servers dialog box that appears.

    5. Configure the task objects.

      1. On the Configure Objects page, configure the objects that you want to migrate.

        Parameter

        Description

        Migration Types

        • For a full data migration only, select Schema Migration and Full Data Migration.

        • For a zero-downtime migration, select Schema Migration, Full Data Migration, and Incremental Data Migration.

        Note

        • If you select Full Data Migration, the schema and data of tables created with the CREATE TABLE statement can be migrated to the destination database.

        • If you do not select Incremental Data Migration, do not write new data to the source instance during the data migration to ensure data consistency.

        Processing Mode of Conflicting Tables

        • Precheck and Report Errors: Checks whether tables with the same names exist in the destination database. If no tables with the same names exist, the precheck is passed. If tables with the same names exist, an error is reported during the precheck, and the data migration task does not start.

          Note

          If a table in the destination database has the same name but cannot be easily deleted or renamed, you can change the name of the table in the destination database. For more information, see Object name mapping.

        • Ignore Errors and Proceed: Skips the check for tables with the same names.

          Warning

          Selecting Ignore Errors and Proceed may cause data inconsistency and business risks. For example:

          • If the table schemas are consistent and a record in the destination database has the same primary key value as a record in the source database:

            • During full migration, DTS keeps the record in the destination database. The record from the source database is not migrated.

            • During incremental migration, DTS does not keep the record in the destination database. The record from the source database overwrites the record in the destination database.

          • If the table schemas are inconsistent, only some columns of data may be migrated, or the migration may fail. Proceed with caution.

        Schema Mapping Mode of Source and Destination Databases

        Select a schema mapping mode as needed to map the schemas between the source and destination databases.

        Warning

        Tables in different schemas of the source database cannot have the same name. Otherwise, data inconsistency or task failure may occur.

        SQL Server Incremental Synchronization Mode

        • Log-based Parsing for Non-heap Tables and CDC-based Incremental Synchronization for Heap Tables (Hybrid Log-based Parsing):

          • Advantages:

            • Supports scenarios that involve source heap tables, tables without primary keys, compressed tables, or tables with computed columns.

            • Provides high link stability. This mode can obtain complete DDL statements and supports a wide range of DDL scenarios.

          • Disadvantages:

            • DTS creates the `dts_cdc_sync_ddl` trigger, the `dts_sync_progress` heartbeat table, and the `dts_cdc_ddl_history` DDL storage table in the source database. It also enables database-level CDC and CDC for some tables.

            • You cannot execute `SELECT INTO`, `TRUNCATE`, or `RENAME COLUMN` statements on tables with CDC enabled in the source database. You cannot manually delete triggers created by DTS in the source database.

        • Incremental Synchronization Based on Logs of Source Database (Heap tables are not supported):

          • Advantage:

            This mode is non-intrusive to the source database.

          • Disadvantage:

            This mode does not support scenarios that involve source heap tables, tables without primary keys, compressed tables, or tables with computed columns.

        • Polling and querying CDC instances for incremental synchronization:

          • Advantages:

            • Supports full and incremental migration when the source database is Amazon RDS for SQL Server, Azure SQL Database, Azure SQL Managed Instance, Azure SQL Server on Virtual Machine, or Google Cloud SQL for SQL Server.

            • This mode uses the native CDC component of SQL Server to obtain incremental data, which improves the stability of incremental migration and reduces network bandwidth usage.

          • Disadvantages:

            • The source database account used by the DTS instance must have the permissions to enable CDC. Incremental data migration has a latency of about 10 seconds.

            • When you migrate multiple tables across multiple databases, you may encounter stability and performance issues.

        Note

        This parameter is available only if you select Incremental Data Migration for the Migration Types parameter.

        The maximum number of tables for which CDC is enabled that DTS supports.

        You can set a limit on the number of CDC-enabled tables for the current migration instance based on your business requirements. The default value is 1,000.

        Note

        This parameter is not available if you set SQL Server Incremental Synchronization Mode to Incremental Synchronization Based on Logs of Source Database (Heap tables are not supported).

        Select DDL and DML to Sync at the Instance Level

        Select the SQL operations for incremental migration at the instance level. For information about the supported operations, see SQL operations supported for incremental migration.

        Note

        To select SQL operations for incremental migration at the database or table level, right-click a migration object in the Selected Objects box and select the desired SQL operations.

        Source Objects

        In the Source Objects box, click the objects to migrate, and then click Right arrow to move them to the Selected Objects box.

        Note

        This scenario is a migration between heterogeneous databases. Therefore, the granularity for selecting migration objects is table. Other objects such as views, triggers, and stored procedures are not migrated to the destination database.

        Selected Objects
        Note

        • If you use the object name mapping feature, the migration of other objects that depend on the renamed object may fail.

        • To set a WHERE condition to filter data, right-click the table to be migrated in the Selected Objects section and specify the filter condition in the dialog box that appears. For instructions, see Set filter conditions.

        • To select SQL operations to be migrated at the database or table level, right-click the migration object in the Selected Objects section and select the desired SQL operations in the dialog box that appears.

      2. Click Next: Advanced Settings to configure advanced parameters.

        Parameter

        Description

        Dedicated Cluster for Task Scheduling

        By default, DTS schedules tasks on a shared cluster. You do not need to select one. If you want more stable tasks, you can purchase a dedicated cluster to run DTS migration tasks.

        Retry Time for Failed Connections

        After the migration task starts, if the connection to the source or destination database fails, DTS reports an error and immediately begins to retry the connection. The default retry duration is 720 minutes. You can customize the retry time to a value from 10 to 1440 minutes. We recommend that you set the duration to more than 30 minutes. If DTS reconnects to the source and destination databases within the specified duration, the migration task automatically resumes. Otherwise, the task fails.

        Note

        • For multiple DTS instances that share the same source or destination, the network retry time is determined by the setting of the last created task.

        • Because you are charged for the task during the connection retry period, we recommend that you customize the retry time based on your business needs, or release the DTS instance as soon as possible after the source and destination database instances are released.

        Retry Time for Other Issues

        After the migration task starts, if a non-connectivity issue, such as a DDL or DML execution exception, occurs in the source or destination database, DTS reports an error and immediately begins to retry the operation. The default retry duration is 10 minutes. You can customize the retry time to a value from 1 to 1440 minutes. We recommend that you set the duration to more than 10 minutes. If the related operations succeed within the specified retry duration, the migration task automatically resumes. Otherwise, the task fails.

        Important

        The value of Retry Time for Other Issues must be less than the value of Retry Time for Failed Connections.

        Enable Throttling for Full Data Migration

        During full migration, DTS consumes read and write resources on the source and destination databases, which may increase the database load. If required, you can enable throttling for the full migration task. You can set Queries per second (QPS) to the source database, RPS of Full Data Migration, and Data migration speed for full migration (MB/s) to reduce the load on the destination database.

        Note

        • This configuration item is available only if you select Full Data Migration for Migration Types.

        • You can also adjust the full migration speed after the migration instance is running.

        Enable Throttling for Incremental Data Migration

        If required, you can also choose to set speed limits for the incremental migration task. You can set RPS of Incremental Data Migration and Data migration speed for incremental migration (MB/s) to reduce the load on the destination database.

        Note

        • This configuration item is available only if you select Incremental Data Migration for Migration Types.

        • You can also adjust the incremental migration speed after the migration instance is running.

        Environment Tag

        You can select an environment tag to identify the instance based on your requirements. This example does not require you to select a tag.

        Configure ETL

        Choose whether to enable the extract, transform, and load (ETL) feature. For more information, see What is ETL? Valid values:

        Monitoring and Alerting

        Select whether to set alerts and receive alert notifications based on your business needs.

        • No: Does not set an alert.

        • Yes: Configure alerts by setting an alert threshold and an alert notifications. If a migration fails or the latency exceeds the threshold, the system sends an alert notification.

      3. Click Next: Data Validation to configure a data validation task.

        For more information about the data validation feature, see Configure data validation.

      4. Optional: After you complete the preceding configurations, click Next: Configure Database and Table Fields to set the Type, Primary Key Column, Distribution Key, and partition key information (Partition Key, Partitioning Rules, and Partition Lifecycle) for the tables to be migrated in the destination database.

        Note

        • This step is available only if you select the Schema Migration option for Migration Types when you configure task objects. You can select All for Definition Status to make modifications.

        • You can select multiple columns for Primary Key Column to form a composite primary key. You must also select one or more columns from the Primary Key Column to use as the Distribution Key and Partition Key. For more information, see CREATE TABLE.

    6. Save the task and run a precheck.

      • To view the parameters for configuring this instance when you call the API operation, move the pointer over the Next: Save Task Settings and Precheck button and click Preview OpenAPI parameters in the bubble that appears.

      • If you do not need to view or have finished viewing the API parameters, click Next: Save Task Settings and Precheck at the bottom of the page.

      Note

      • Before the migration task starts, DTS performs a precheck. The task starts only after it passes the precheck.

      • If the precheck fails, click View Details next to the failed check item, fix the issue based on the prompt, and then run the precheck again.

      • If a warning is reported during the precheck:

        • For check items that cannot be ignored, click View Details next to the failed item, fix the issue based on the prompt, and then run the precheck again.

        • For check items that can be ignored, you can click Confirm Alert Details, Ignore, OK, and Precheck Again to skip the alert item and run the precheck again. If you choose to ignore a warning, it may cause issues such as data inconsistency and pose risks to your business.

    7. Purchase an instance.

      1. When the Success Rate is 100%, click Next: Purchase Instance.

      2. On the Purchase page, select the link specification for the data migration instance. For more information, see the following table.

        Category

        Parameter

        Description

        New Instance Class

        Resource Group Settings

        Select the resource group to which the instance belongs. The default value is default resource group. For more information, see What is Resource Management?

        Instance Class

        DTS provides migration specifications with different performance levels. The link specification affects the migration speed. You can select a specification based on your business scenario. For more information, see Data migration link specifications.

      3. After the configuration is complete, read and select Data Transmission Service (Pay-as-you-go) Service Terms.

      4. Click Buy and Start. In the OK dialog box that appears, click OK.

        You can view the progress of the migration task on the Data Migration Tasks list page.

        Note

        • If the migration task does not include incremental migration, it stops automatically after the full migration is complete. After the task stops, its Status changes to Completed.

        • If the migration task includes incremental migration, it does not stop automatically. The incremental migration task continues to run. While the incremental migration task is running, the Status of the task is Running.