Differences Between MySQL and SQL Server
MSSQL (SQL Server) originated as a product of collaboration between Sybase and Microsoft.
For developers, the two most commonly used backend databases are currently MySQL and SQL Server. Their fundamental similarity lies in data storage and querying systems. You can use SQL to access data in both databases, as they both support ANSI-SQL. Additionally, both systems support binary keywords and key indexing, which significantly speeds up query performance. They also provide support for various XML formats.
However, the primary difference between the two lies in their underlying principles: open vs. conservative. SQL Server’s storage engine is narrow and conservative compared to the extensible and open storage engines of MySQL. While SQL Server uses Sybase's engine, MySQL offers more options such as MyISAM, Heap, InnoDB, and Berkeley DB. MySQL has limited support for certain keywords, which reduces some database functionality compared to SQL Server. It also lacks some stored procedure features; for example, MyISAM supports table exchange but is limited in other aspects.
Below is a comparison of the two databases based on cost, performance, security, recoverability, and selection criteria.
Cost Comparison: MySQL is not entirely free but is very affordable
For SQL Server, one of the common ways to obtain a free developer license is through purchasing Microsoft Office or Visual Studio. However, for commercial product development, you must purchase SQL Server Standard Edition. Schools or non-profit organizations might not incur these additional costs.
Performance Comparison: Advanced MySQL
In terms of performance, MySQL excels with its default table format, MyISAM. MyISAM databases are highly compatible with disks without consuming too much CPU and memory. MySQL runs well on Windows and even better on UNIX or UNIX-like systems. You can also gain additional performance by using a 64-bit processor, as MySQL often internally utilizes 64-bit integer processing. Yahoo’s commercial website, for example, uses MySQL as its backend database.
For software stability, SQL Server outshines its competitors. However, this stability comes with a cost, such as increased operational complexity, higher disk storage needs, and greater memory consumption. If your hardware and software cannot adequately support SQL Server, it might be better to choose another database system like DBMS for better results. Both MySQL and SQL Server can run on .NET or J2EE environments and support RAID configurations.
Security
MySQL provides a binary log for data modification. Because it is binary, this log can quickly replicate data from the host to the client. Even in case of a server crash, the binary log remains intact, and the replicated portions are not corrupted. In SQL Server, you can also record SQL-related queries, but this comes at a high cost.
Both products have robust security mechanisms. If you adhere to these mechanisms, there are generally no major issues in program security. Both databases use default IP ports, which can sometimes be exploited by hackers. However, you can manually configure these IP ports for added security.
Recoverability: Advanced SQL Server
Recoverability is a feature of MySQL, particularly in the MyISAM configuration. However, it has inherent flaws. If the database is accidentally damaged, it could result in complete data loss. On the other hand, SQL Server is much more reliable. It can continuously monitor data exchange points and preserve the process of database corruption, ensuring greater data safety.
Selection Criteria: Decide Based on Your Needs
If you want to build a .NET server system that can manage databases and allow access from multiple platforms, choose SQL Server.
If you want to build a third-party website that can read data from some clients, MySQL is the better choice.
