The latest articles on DEV Community by stackOverflowed (@soverflowed). https://dev.to/soverflowed https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F155427%2Fafec3d7c-e81a-4aa1-bb22-9caa8d7e8eb3.jpg https://dev.to/soverflowed en stackOverflowed Thu, 01 Aug 2019 19:31:06 +0000 https://dev.to/soverflowed/what-happens-when-you-submit-a-query-3e96 https://dev.to/soverflowed/what-happens-when-you-submit-a-query-3e96 <p>If you have some experience working with databases, you may certainly used several SQL commands. Have you wondered what happens when a query is submitted? How does the query optimizer work ?</p> <p>When a query is submitted to a SQL Server, a number of processes on the server are set into motion. </p> <p>However, primarily it focuses on 2 stages:</p> <ol> <li>Relational engine processes.</li> <li>Storage engine processes. </li> </ol> <p>In a RDBMS, in the first stage of the process, a query is parsed and then processed by the query optimizer, which generates an execution plan. The execution plan which is in binary format, is sent to the storage engine. </p> <p>The storage engine then uses that plan as a basis to retrieve or modify the underlying data. The storage engine is where processes such as locking, index maintenance and transactions occur.</p> <p>That's pretty much the gist of it. </p> mssqlserver rdbms