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In today's data-driven world, system logging is an essential aspect of any enterprise database system. The ability to track, monitor, and analyze system events is crucial for system management, performance tuning, troubleshooting, and security auditing. This blog post will guide you through the process of setting up a central logging framework using T-SQL, with a focus on SQL Server 2012/2014, MySQL 5.6, DB2 10.5, and Azure SQL.

Let's begin with SQL Server. SQL Server provides a feature called Extended Events, which allows capturing detailed system and user events. To create a central logging framework, we can set up an Extended Event session and configure it to write the events to a target, such as a file or the Windows event log.

-- Create an Extended Event session in SQL Server
CREATE EVENT SESSION [MySession] ON SERVER 
ADD EVENT sqlserver.sql_batch_completed(SET collect_batch_text=(1))
ADD TARGET package0.event_file(SET filename=N'MySession.xel')
WITH (MAX_MEMORY=4096 KB,EVENT_RETENTION_MODE=ALLOW_SINGLE_EVENT_LOSS,MAX_DISPATCH_LATENCY=30 SECONDS,MAX_EVENT_SIZE=0 KB,MEMORY_PARTITION_MODE=NONE,TRACK_CAUSALITY=OFF)
GO

Next, let's look at MySQL. MySQL offers a feature called the General Query Log, which logs every query that is sent to the server. To capture the logs centrally, you can configure the server to write the logs to a file or a table.

-- Enable the General Query Log in MySQL
SET GLOBAL general_log = 'ON';
SET GLOBAL log_output = 'TABLE';

For DB2, you can use the DB2 Audit Facility, which provides comprehensive auditing capabilities. You can configure it to capture various types of events, such as database operations, security events, and system events, and write them to a log file.

-- Enable auditing in DB2
db2 update dbm cfg using audit_buf_sz 500
db2 update dbm cfg using audit_trail recno
db2set DB2AUDIT=YES
db2audit start

Finally, for Azure SQL, you can use Azure Monitor, which provides a central platform for monitoring all your Azure resources. It captures a wide range of data, including metrics, logs, and events, and stores them in a Log Analytics workspace for analysis and visualization.

In conclusion, a central logging framework is an essential tool for managing and monitoring your database systems. By leveraging the built-in features of SQL Server, MySQL, DB2, and Azure SQL, you can easily set up a robust and efficient logging framework that meets your needs.

Remember, no matter the size of your database or the scale of your operations, a well-structured logging system is vital. It not only ensures smooth operations but also provides valuable insights for performance optimization and security enhancements. Happy Logging!