Limitations of a Managed Cloud Database Service
With the advent of cloud computing, several managed services for databases have become available. Whether to use a managed cloud database service from a cloud provider depends on several factors, and it may not be the best choice for some.
Let’s look at some of the limitations of managed cloud database services so you can better decide what makes sense for you.
Admin Access Is Not Provided
Being a managed cloud-based database service, administrator access to the database is often not provided. As a result, a database user has to depend on the configuration settings provided by the service provider. Some initialization parameters may not be modifiable; for instance, a user usually wouldn’t be able to run some administrator-level SQL commands.
Some Patches May Not Have Been Installed
Though most cloud service providers install all essential patches, some special-purpose patches may not have been installed by default, so you may have to request them from cloud service support.
The Database Version May Not Be the Latest
The latest database version may not be available on a managed database service. As a result, all new features may not be available.
There Are Resource Limits
Managed cloud-based database services often have limits on resources, such as the number of instances that may be created, the number of CPU cores and amount of RAM, and the storage that may be allocated. Some naming constraints for database names and the like may also exist. The number of database concurrent connections could also be limited.
Some Data Types Are Not Supported
Some advanced data types, such as media types or spatial and graph types, may not be supported when creating a table. Some CREATE TABLE and ALTER TABLE clauses may not be supported either.
Some Database Features May Not Be Provided
Some advanced database features may not be supported in a managed database service. The features omitted could be a programming language (Java, for example) that is not supported, some performance tuning that is not available to a user, or a database backup that cannot be initiated by a user. A managed database service also may not include some analytics and RESTful services or the in-memory database features that are available in downloaded binaries.
File System Access Is Not Provided
Access to the host file system is usually not available in a managed database service. A user may not be able to store files on the host file system.
Client Access Is Limited
Client access may be limited in terms of the operating systems (Windows, Linux, or MacOS) supported, client tools that may be used, and client programming language APIs that could be used.
While managed database services provided by some cloud providers have their benefits in terms of ease of usability, the limitations listed here should be kept in consideration when opting for a managed database service.
This is a very good summary of the issues.