SQLmoottori
SQLmoottori is a term that translates to "SQL engine" in English. It refers to the software component within a database management system (DBMS) that is responsible for processing and executing SQL (Structured Query Language) commands. When a user or application submits a query written in SQL, it is the SQL engine that interprets this query, determines the most efficient way to retrieve or modify the requested data, and then interacts with the storage manager to perform the actual data operations. Key functions of a SQL engine include query parsing, query optimization, query execution, and transaction management. The query parser checks the SQL syntax for errors. The query optimizer analyzes the query and creates an execution plan, choosing the best strategies for accessing data, often involving indexes. The query execution component then carries out this plan. Transaction management ensures data integrity and consistency, especially in environments with multiple concurrent users. Different database systems, such as MySQL, PostgreSQL, SQL Server, and Oracle, each have their own proprietary SQL engines with varying architectures and optimization techniques, leading to performance differences for similar workloads.