Limitations and Quotas of TiDB Cloud Starter and Essential

TiDB Cloud Starter and Essential work with almost all workloads that TiDB supports, but there are some feature differences compared with TiDB Self-Managed or TiDB Cloud Dedicated clusters. This document describes the limitations of TiDB Cloud Starter and TiDB Cloud Essential.

We are constantly filling in the feature gaps between TiDB Cloud Starter/Essential and TiDB Cloud Dedicated. If you require these features or capabilities in the gap, use TiDB Cloud Dedicated or contact us for a feature request.

Limitations

Audit logs

• Database audit logging is currently unavailable.

Connection

• Only Public Endpoint and Private Endpoint can be used. You cannot use VPC Peering to connect to TiDB Cloud Starter or TiDB Cloud Essential clusters. 
• No IP Access list support.

Encryption

• Data persisted in your TiDB Cloud Starter or TiDB Cloud Essential cluster is encrypted using the encryption tool provided by the cloud provider that manages your cluster. For TiDB Cloud Starter (with spending limit > 0) and TiDB Cloud Essential clusters, an optional second layer of encryption is available during the cluster creation process, providing an additional level of security beyond the default encryption at rest.
• Using customer-managed encryption keys (CMEK) is currently unavailable.

Maintenance window

• Maintenance window is currently unavailable.

Monitoring and diagnosis

• Third-party Monitoring integrations are currently unavailable.
• Built-in Alerting is currently unavailable.
• Key Visualizer is currently unavailable.

Self-service upgrades

• TiDB Cloud Starter and TiDB Cloud Essential are fully managed deployments of TiDB. Major and minor version upgrades of TiDB Cloud Starter and TiDB Cloud Essential are handled by TiDB Cloud and therefore cannot be initiated by users.

Stream data

• Changefeed is not supported for TiDB Cloud Starter and TiDB Cloud Essential currently.
• Data Migration is not supported for TiDB Cloud Starter and TiDB Cloud Essential currently.

Time to live (TTL)

• In TiDB Cloud Starter and TiDB Cloud Essential, the TTL_JOB_INTERVAL attribute for a table is fixed at 15m and cannot be modified. This means that TiDB Cloud Starter and TiDB Cloud Essential schedule a background job every 15 minutes to clean up expired data.

Others

• Transaction can not last longer than 30 minutes.
• For more details about SQL limitations, refer to Limited SQL Features.

Usage quota

For each organization in TiDB Cloud, you can create a maximum of five free TiDB Cloud Starter clusters by default. To create more TiDB Cloud Starter clusters, you need to add a credit card and set a monthly spending limit for the usage.

For the first five TiDB Cloud Starter clusters in your organization, TiDB Cloud provides a free usage quota for each of them as follows:

• Row-based storage: 5 GiB
• Columnar storage: 5 GiB
• Request Units (RUs): 50 million RUs per month

The Request Unit (RU) is a unit of measurement used to track the resource consumption of a query or transaction. It is a metric that allows you to estimate the computational resources required to process a specific request in the database. The request unit is also the billing unit for TiDB Cloud Starter service.

Once a cluster reaches its usage quota, it immediately denies any new connection attempts until you increase the quota or the usage is reset upon the start of a new month. Existing connections established before reaching the quota will remain active but will experience throttling.

To learn more about the RU consumption of different resources (including read, write, SQL CPU, and network egress), the pricing details, and the throttled information, see TiDB Cloud Starter Pricing Details.

If you want to create a TiDB Cloud Starter cluster with an additional quota, you can set the monthly spending limit on the cluster creation page. For more information, see Create a TiDB Cloud Starter cluster.

After creating a TiDB Cloud Starter cluster, you can still check and edit the spending limit on your cluster overview page. For more information, see Manage Spending Limit for TiDB Cloud Starter Clusters.