This topic describes the limits and requirements of TSQL. Before you use TSQL, make sure that the specified limits and requirements are met.
- Currently, TSQL allows you to only read time series data. You can use TSQL to delete and write time series data in later versions.
- Currently, TSQL supports only the single-value data model for time series data, and does not support the multi-value data model for time series data. For single table queries, TSDB can return metric values from a single raw column for each metric, and the relevant computed columns that use functions. For single table queries, TSDB cannot return multiple raw columns for metric fields.
TSQL was released in Time Series Database (TSDB) V3.0.0 on April 3, 2019. By default, TSQL is not enabled for the instances that you purchased or created before April 3, 2019. To enable TSQL, you must submit a ticket to upgrade your instances to the latest version.
- For the TSDB service that you purchased after July 23, 2019, all instance types support TSQL.
- For the TSDB service that you purchased before July 23, 2019, TSQL is supported only by the instances whose instance type is at least 3xlarge. This is because TSQL has high requirements on the hardware resources of your instances to ensure high stability. To enable TSQL for the instances whose instance types are less advanced than 3xlarge, upgrade the instances to the latest version.