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SQL Server 2019, MySQL 8.0, DB2 11.5, Azure SQL, and Azure Synapse all offer robust ways to manage and configure databases. One such method is through database scoped configurations. These configurations allow you to tailor database settings without impacting the whole server. They are especially useful for managing settings that are specific to a particular database, allowing for more flexibility and control when adjusting performance and behavior.

In SQL Server 2019, database scoped configurations are a set of options that affect the behavior of a single, specific database. This is extremely useful as it gives administrators the ability to tailor behavior without impacting other databases on the server. A simple example of enabling the MAXDOP configuration for a specific database can be seen below:

-- T-SQL code for SQL Server 2019

ALTER DATABASE SCOPED CONFIGURATION SET MAXDOP = 2;

In MySQL 8.0, while there isn't a direct equivalent to SQL Server's database scoped configurations, similar functionality can be achieved using system variables. These variables can be set at a server or session level, with session variables taking precedence over server ones. A session in MySQL corresponds to a connection to a database, and changes to session variables are only visible to that session. For example, the following command sets the session variable 'wait_timeout' to 60 seconds:

-- MySQL code
SET SESSION wait_timeout = 60;

DB2 11.5 has a feature called Database Configuration Advisor (DBCA) which, though not identical, is similar to SQL Server's Database Scoped Configurations. DBCA helps in managing and tuning database configuration parameters. Parameters can be set at the database level, allowing for granular control.

Azure SQL, very much like SQL Server, also supports database scoped configurations, making it possible to customize specific database settings without affecting other databases. Azure Synapse, previously SQL Data Warehouse, provides similar functionality through its resource classes, which allow for control over the amount of memory and concurrency slots that queries can use. This is ideal for managing performance across different workloads.

In conclusion, database scoped configurations are a powerful tool for database administrators, providing the ability to customize settings at a database-specific level. They offer a great deal of flexibility and control, allowing for tailored performance and behavior. Whether you're using SQL Server 2019, MySQL 8.0, DB2 11.5, Azure SQL, or Azure Synapse, understanding and utilizing these configurations can greatly enhance your database management capabilities.