Limitations in Azure Database for MySQL

The following sections describe capacity, storage engine support, privilege support, data manipulation statement support, and functional limits in the database service. Also see general limitations applicable to the MySQL database engine.

Service tier maximums

Azure Database for MySQL has multiple service tiers to choose from when creating a server. For more information, see Azure Database for MySQL pricing tiers.

There is a maximum number of connections, Compute Units, and storage in each service tier, as follows:

Pricing Tier Compute Generation vCore(s) Max Connections
Basic Gen 4 1 50
Basic Gen 4 2 100
Basic Gen 5 1 50
Basic Gen 5 2 100
General Purpose Gen 4 2 300
General Purpose Gen 4 4 625
General Purpose Gen 4 8 1250
General Purpose Gen 4 16 2500
General Purpose Gen 4 32 5000
General Purpose Gen 5 2 300
General Purpose Gen 5 4 625
General Purpose Gen 5 8 1250
General Purpose Gen 5 16 2500
General Purpose Gen 5 32 5000
Memory Optimized Gen 5 2 600
Memory Optimized Gen 5 4 1250
Memory Optimized Gen 5 8 2500
Memory Optimized Gen 5 16 5000

When too many connections are reached, you may receive the following error:

ERROR 1040 (08004): Too many connections

Storage engine support

Supported

Unsupported

Privilege support

Unsupported

  • DBA role: Many server parameters and settings can inadvertently degrade server performance or negate ACID properties of the DBMS. As such, to maintain the service integrity and SLA at a product level, this service does not expose the DBA role. The default user account, which is constructed when a new database instance is created, allows that user to perform most of DDL and DML statements in the managed database instance.
  • SUPER privilege: Similarly SUPER privilege is also restricted.

Data manipulation statement support

Supported

  • LOAD DATA INFILE - Supported, but it must specify the [LOCAL] parameter that is directed to a UNC path (Azure storage mounted through XSMB).

Unsupported

  • SELECT ... INTO OUTFILE

Functional limitations

Scale operations

  • Dynamic scaling of servers across pricing tiers is currently not supported. That is, switching between Basic, General Purpose, and Memory Optimized pricing tiers.
  • Decreasing server storage size is not supported.

Server version upgrades

  • Automated migration between major database engine versions is currently not supported.

Point-in-time-restore

  • Restoring to different service tier and/or Compute Units and Storage size is not allowed.
  • Restoring a deleted server is not supported.

Functional limitations

Subscription management

  • Dynamically moving pre-created servers across subscription and resource group is currently not supported.

Current known issues

  • MySQL server instance displays the wrong server version after connection is established. To get the correct server instance versioning, use select version(); command at the MySQL prompt.

Next steps