This topic describes the limits of ApsaraDB RDS for SQL Server. You must understand the limits to make instances more stable and secure.

ApsaraDB RDS for SQL Server instances are provided with Microsoft SQL Server licenses. You cannot use your own licenses. The following table lists other limits.

Feature Cluster Edition High-availability Edition Basic Edition
2017 EE

2019 SE

2017 SE

2016 SE and 2016 EE

2014 SE

2012 SE and 2012 EE

2008 R2

2012 Web and 2016 Web

2012 SE and 2016 SE

2012 EE Basic

2016 EE

Maximum number of databases (Maximum number of databases) 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 data definition language (DDL) trigger Supported Supported Not supported Supported
Database permission authorization Supported Supported Not supported Supported
KILL permission Supported Supported Supported Supported
Linked server Supported Supported 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 Not supported Not supported Not supported
Change tracking Supported Supported Not supported Supported
Windows domain account logon Not supported Not supported Not supported Not supported
Email
SQL Server Integration Services (SSIS)
SQL Server Analysis Services (SSAS)
SQL Server Reporting Services (SSRS)
R Services
Common Language Runtime (CLR)
Asynchronous communication
Replication
Policy management
Note If you encounter other problems about limits, you can submit a ticket.

Maximum number of databases

An ApsaraDB for RDS instance that runs SQL Server 2008 R2 supports up to 50 databases. In the other SQL Server versions, the maximum number of databases varies based on the instance type. You can use the following formulas to calculate the maximum number of databases:
  • Cluster and High-availability Editions

    The maximum number obtained from the preceding formula cannot exceed 300.

  • Basic Edition

    The maximum number obtained from the preceding formula cannot exceed 400.