- What's New
- Service Overview
- Getting Started
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User Guide
- Function Overview
- Permissions Management
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Instance Management
- Buying a DDM Instance
- Splitting Read-only and Read-Write Services
- Changing Class of a DDM Node
- Scaling Out a DDM Instance
- Scaling In a DDM Instance
- Changing Billing Mode of a DDM Instance
- Renewing a DDM Instance
- Restarting a DDM Instance
- Unsubscribing from a DDM Instance
- Deleting a DDM Instance
- Modifying Parameters of a DDM Instance
- Splitting Read and Write Requests
- Configuring a Parameter Template
- Connection Management
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Parameter Template Management
- Creating a Parameter Template
- Editing a Parameter Template
- Comparing Two Parameter Templates
- Viewing Parameter Change History
- Replicating a Parameter Template
- Applying a Parameter Template
- Viewing Application Records of a Parameter Template
- Modifying the Description of a Parameter Template
- Deleting a Parameter Template
- Task Center
- Schema Management
- Shard Configuration
- Data Node Management
- Account Management
- Backups and Restorations
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Data Migration
- Overview
- Migration Evaluation
- Scenario 1: Migrating Data from Huawei Cloud RDS to DDM
- Scenario 2: Migrating Data from an On-Premises RDS Instance for MySQL to DDM
- Scenario 3: Migrating Data from a Third-Party RDS for MySQL Instance to DDM
- Scenario 4: Migrating Data from a Self-Built MySQL Instance to DDM
- Scenario 5: Migrating Data from Heterogeneous Databases to DDM
- Scenario 6: Exporting Data from a DDM Instance
- Slow Queries
- Monitoring Management
- Auditing
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SQL Syntax
- Introduction
- DDL
- DML
- Functions
- Use Constraints
- Supported SQL Statements
- Global Sequence
- Database Management Syntax
- Advanced SQL Functions
- Quotas
- Change History
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API Reference
- Before You Start
- API Overview
- Calling APIs
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APIs (Recommended)
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DDM Instances
- Buying a DDM instance
- Querying DDM Instances
- Querying Details of a DDM Instance
- Modifying the Name of a DDM Instance
- Modifying the Security Group of a DDM Instance
- Deleting a DDM Instance
- Restarting a DDM Instance
- Reloading Table Data
- Scaling out a DDM instance
- Scaling in a DDM instance
- Modifying the Read Policy of the Associated DB Instance
- Synchronizing Data Node Information
- Querying Nodes of a DDM Instance
- Querying Details of a DDM Instance Node
- Querying Parameters of a Specified DDM Instance
- Modifying Parameters of a DDM Instance
- Querying DDM Engine Information
- Querying DDM Node Classes Available in an AZ
- Changing the Node Class of a DDM Instance
- Schemas
- DDM Accounts
- Monitoring
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DDM Instances
- APIs (Unavailable Soon)
- Appendix
- Change History
- SDK Reference
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Best Practices
- Overview
- Formulating Sharding Rules
- Determining the Number of Shards in a Schema
- Using Broadcast and Unsharded Tables
- Transaction Models
- SQL Standards
- Migrating an Entire RDS Database to DDM
- Migrating an Entire MyCat Database to DDM
- Accessing DDM Using a JDBC Connection Pool
- Logging In to a DDM Instance Using Navicat
- Migrating Data from RDS for MySQL to DDM Using DRS
- Performance White Paper
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FAQs
- General Questions
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DDM Usage
- How Does DDM Perform Sharding?
- What Do I Do If I Fail to Connect to a DDM Instance Using the JDBC Driver?
- What Version and Parameters Should I Select?
- Why It Takes So Long Time to Export Data from MySQL Using mysqldump?
- What Do I Do If a Duplicate Primary Key Error Occurs When Data Is Imported into DDM?
- What Should I Do If an Error Message Is Returned When I Specify an Auto-Increment Primary Key During Migration?
- What Do I Do If an Error Is Reported When Parameter Configuration Does Not Time Out?
- Which Should I Delete First, a Schema or its Associated RDS Instances?
- Can I Manually Delete Databases and Accounts Remained in Data Nodes After a Schema Is Deleted?
- SQL Syntax
- RDS-related Questions
- Connection Management
- Resource Freezing, Release, Deletion, and Unsubscription
- Change History
- Videos
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Creating a User and Granting Permissions
If your account does not need individual IAM users, then you may skip over this section.
This chapter describes fine-grained permissions management on DDM. For details, see Service Overview > What Is IAM in the Identity and Access Management User Guide.
- Create IAM users for employees based on the organizational structure of your enterprise. Each IAM user has their own security credentials, providing access to DDM resources.
- Grant only the permissions required for users to perform a specific task.
- Entrust an account or cloud service to perform professional and efficient O&M on your DDM resources.
This section describes the procedure for granting permissions.
Prerequisites
Before assigning permissions to user groups, you should learn about DDM system policies and select the policies based on service requirements. For details about the system permissions supported by DDM, see Service Overview > Permissions Management in the Distributed Database Middleware User Guide. For the system policies of other services, see System Permissions > System Permissions.
Process Flow
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- Create a user group and assign permissions to it.
Create a user group on the IAM console, and assign the DDM ReadOnlyAccess policy to the group.
- Create an IAM user and add it to a user group.
Create a user on the IAM console and add the user to the group created in step 1.
- Log in and verify permissions.
Log in to the DDM console using the created user, and verify that the user only has read permissions for DDM.
- Choose Service List > Distributed Database Middleware and click Buy DDM Instance to buy a DDM instance. If you cannot buy a DDM instance, the DDM ReadOnlyAccess permission has taken effect.
- Choose any other service in the Service List (assuming that there is only the DDM ReadOnlyAccess policy). If a message appears indicating insufficient permissions to access the service, the DDM ReadOnlyAccess policy has already taken effect.
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