What database management systems have you already worked with?

I have worked with several database management systems (DBMS):

• MySQL — frequently used for web applications, well-versed in writing queries, indexing, and optimization.
• PostgreSQL — used for more complex projects requiring support for advanced data types and transactions.
• SQLite — used for small applications and testing, due to its lightweight and simplicity.

I also have experience working with NoSQL databases, such as MongoDB, for storing unstructured data.