How can you secure databases for optimal performance?

There are several ways to secure your database, few of them are as follows 1. Following the principle of least privilege's. 2. Reducing the surface area of attacks like changing the default port, setting firewall rules, not exposing database server to public network. 3. Enabling TDE for protecting data at rest. 4. Enabling Always encryption and dynamic data masking. 5. Disabling the sa account. These ways do not have much or any impact on the database performance. Security and performance are two independent factors.

Authentication: Verifies user or system identity before granting database access. * Strong passwords * Encryption * Multi-factor authentication Authorization: Dictates permissions and privileges for specific database objects (tables, views, procedures, functions). Principle of least privilege: Grant minimal necessary permissions, revoke when no longer needed.

Encryption - Scrambling data : Renders data unreadable without the correct decryption key * Transparent Data Encryption (TDE) * Always Encrypted * Column-level encryption * Backup encryption Masking- Obscuring sensitive data: Replaces or partially obscures sensitive information with surrogate values. * Dynamic Data Masking * Static data masking Key difference- Encryption: Data is scrambled, requiring decryption for meaningful use. Masking: Data is transformed but remains usable, original values cannot be recovered.

This is one of the best practice all DBAs must follow that is auditing and monitoring databases and database servers. There is a C2 audit (default) in SQL Server which we can enable. There are another database and instance level audit mechanisms available in SQL Server with which we can design and track everything going on in database. We can use scripts as well as third party monitoring tools to monitor the databases that will help us with the performance baseline and statistics. Some famous tools are like scom, solarwinds, idera etc. There are some in build features in SQL Server like activity monitor, server dashboard, profiler, DMV & DMFs, etc. and there is an application called perfmon in windows OS that can also help to some extent.

Stay up-to-date with support cycles: Microsoft has specific lifecycle policies for different SQL Server versions. Prioritize security updates: Address critical vulnerabilities promptly. Align with organizational policies: Follow established guidelines for change management and testing. Regular patching and updating are essential for maintaining the security, performance, and compliance of your SQL Server environments. Service Packs (SPs): Major updates, often including cumulative fixes and new features. Cumulative Updates (CUs): Regularly released bundles of hotfixes and security patches. General Distribution Releases (GDRs): Critical security fixes for specific issues. With the latest SQL Server 2022 MS stopped releasing SPs.

Performance tuning your slow running queries should be in the top list for optimal performance. Having coding standard documentation can be really beneficial within the teams. Having regular team meetings to discuss the latest features that can make the performance tuning easier can be helpful. Considering upgrading your old database servers to the latest versions can also bring all the inbuilt tuning automated capabilities without changing much settings except the latest compat mode of the database. One of the example for SQL Server is Intelligent query processing features.

The title of the article is misleading since it suggests that securing a database leads to optimal performance, but in reality, security and performance are separate matters. To enhance security, prioritize data protection, implement audits, and configure appropriate authentication and authorization, including database encryption with customer-managed keys for highly sensitive data. For improved performance, explore strategies like query optimization, effective indexing, data partitioning by region, and the use of replicated cloned databases for reporting and analytical tasks.