This topic describes the limits of ApsaraDB RDS for SQL Server. Before you use ApsaraDB RDS for SQL Server, we recommend that you familiarize yourself with these limits to ensure the stability and security of your database system.
Feature | RDS Cluster Edition | RDS High-availability Edition | RDS Basic Edition | |
SQL Server 2022 EE on RDS Cluster Edition SQL Server 2019 EE on RDS Cluster Edition SQL Server 2017 EE on RDS Cluster Edition | SQL Server 2022 SE SQL Server 2019 SE SQL Server 2017 SE SQL Server 2016 SE and SQL Server 2016 EE SQL Server 2014 SE and SQL Server 2014 EE SQL Server 2012 SE and SQL Server 2012 EE | SQL Server 2008 R2 | SQL Server 2022 Web and SQL Server 2022 SE SQL Server 2019 Web and SQL Server 2019 SE SQL Server 2017 Web and SQL Server 2017 SE SQL Server 2016 Web, SQL Server 2016 SE, and SQL Server 2016 EE SQL Server 2014 SE SQL Server 2012 Web and SQL Server 2012 EE Basic | |
Maximum number of databases (related to the instance type) | 300 | 300 | 50 | 400 |
Maximum number of database accounts | Unlimited | Unlimited | 500 | Unlimited |
Creation of accounts, logon connections, and databases | Supported | Supported | Supported | Supported |
Database-level DDL triggers | Supported | Supported | Not supported | Supported |
Database permission authorization | Supported | Supported | Not supported | Supported |
Permissions to terminate threads | Supported | Supported | Supported | Supported |
Linked server | Supported (Linked servers are not supported for the shared instance family.) | Supported (Linked servers are not supported for the shared instance family.) | Not supported | Not supported |
Distributed transaction | Supported | Supported | Not supported | Not supported |
SQL Profiler | Supported | Supported | Supported | Supported |
Tuning Advisor | Supported | Supported | Not supported | Supported |
Change data capture (CDC) | Supported | Supported (This feature is not supported for SQL Server 2012 SE.) | Supported for RDS instances that use cloud disks Not supported for RDS instances that use local disks | Not supported |
Change tracking | Supported | Supported | Not supported | Supported |
Logon by using Windows domain accounts | Supported (This feature is not supported for the shared instance family.) | Supported (This feature is not supported for the shared instance family.) | Not supported | Not supported |
SQL Server Integration Services (SSIS) | Supported (These features are not supported for the shared instance family.) | Supported (These features are not supported for the shared instance family.) | Not supported | Supported (These features are not supported for the shared instance family.) |
SQL Server Analysis Services (SSAS) | ||||
SQL Server Reporting Services (SSRS) | ||||
Not supported | Not supported | Not supported | Not supported | |
R Services | ||||
Common Language Runtime (CLR) | ||||
Asynchronous communication | ||||
Publishing and subscription management | ||||
Manage policies | ||||
Maximum number of databases
An RDS instance that runs SQL Server 2008 R2 supports up to 50 databases. If your RDS instance runs other SQL Server versions, the maximum number of databases varies based on the RDS edition. You can use the following formulas to calculate the maximum number of databases:
RDS Cluster Edition/RDS High-availability Edition
You must extract the square root of the number of CPU cores, round the square root down to the integer, and then multiply the integer by 50. Assume that the obtained value is X. In this example, the maximum number of databases equals the smaller value between X and 300. For example, if your RDS instance runs SQL Server 2016 SE on RDS High-availability Edition and provides 4 CPU cores and 8 GB of memory, the RDS instance supports a maximum of 100 databases.
RDS Basic Edition
You must extract the square root of the number of CPU cores, round the square root down to the integer, and then multiply the integer by 100. Assume that the obtained value is X. In this example, the maximum number of databases equals the smaller value between X and 400. For example, if your RDS instance runs SQL Server 2019 SE on RDS Basic Edition and provides 4 CPU cores and 8 GB of memory, the RDS instance supports a maximum of 200 databases.
min in the preceding formulas indicates that the smaller value between two values is used. For example, the value of min{100,300} is 100.