Why Cloud Databases Beat Traditional Ones: Safety, Migration, and Analytics

Traditional vs. Cloud Databases

Traditional on‑premise databases require dedicated hardware, periodic upgrades, and strict security policies. Cloud databases provide elastic resources, built‑in high availability, and simplified management.

Advantages of Cloud Databases

Cloud instances use PCI‑e SSDs with performance up to 245,509 QPS and support multiple engines (MySQL, SQL Server, MariaDB, PostgreSQL). A unified web console enables deployment, scaling, backup, recovery, monitoring, and migration. Resources can be provisioned on demand.

Database SaaS Service Model

The SaaS model includes cloud onboarding, daily operations, security auditing, and data subscription for analytics. TencentDB for MySQL can be provisioned in minutes, offers elastic scaling, automated backup, monitoring, rapid scaling, and data transfer.

Data Migration with Data Transmission Service (DTS)

DTS integrates migration, synchronization, and subscription. It supports online, non‑disruptive migration to TencentDB for MySQL from sources reachable via public IP, VPN, dedicated line, or CVM. Batch task management and status monitoring are provided.

MySQL Migration

Source can be an external MySQL instance or a MySQL instance hosted on CVM.

Continuous replication is possible without downtime.

The target TencentDB instance must be empty; the source remains online.

Redis Migration

Supported only for migration to Tencent Cloud Redis master‑slave version.

CVM‑hosted instances cannot be migrated across regions.

Redis 3.2 is not supported due to protocol limitations.

Source instance must be running, without an initialized password, and the target must be empty.

PostgreSQL Migration

Supported PostgreSQL versions: 9.3.x and 9.5.x.

Version 9.3.x does not support incremental sync.

Version 9.5.x requires an online sync plugin for incremental sync.

Database Auditing

Comprehensive Auditing

Records all database access for traceability.

Supports rule‑based selective auditing or full‑volume auditing.

Petabyte‑scale storage with optional long‑term backup.

Efficient Auditing

Implemented via kernel plugins; performance impact <2%.

Provides fast queries on billions of records (e.g., 30 billion rows returned in 6–8 seconds) with filters for user, IP, client, time, SQL type, success, latency, and affected rows.

Data Subscription

DTS offers binlog‑based incremental subscription for TencentDB for MySQL. Users create a subscription channel in the DTS console and consume changes via the DTS SDK.

Messages retained for three days by default.

Full‑database subscription automatically includes newly created tables.

Supported for MySQL 5.6 (future support for 5.7).

Views, triggers, and foreign keys are not included.

Initial setup requires adjusting binlog_row_image parameter; the service will restart affected sessions.

Supported character sets: latin1, utf8, utf8mb4.

Future Outlook

Cloud databases are expected to become core infrastructure, offering on‑demand provisioning, unlimited storage, serverless operation, AI‑driven management, zero‑maintenance, and global auto‑scaling.