Bhavitha Cherukuri: #SQL(DAY4)Do you know the process of SQL?

Do you know the process of SQL?

When we are executing the command of SQL on any Relational database management system, then the system automatically finds the best routine to carry out our request, and the SQL engine determines how to interpret that particular command.

Structured Query Language contains the following four components in its process:

1) Query Dispatcher

The function of the dispatcher is to route the query request to either CQE or SQE, depending on the attributes of the query. All queries are processed by the dispatcher. It cannot be bypassed.

2) Optimization Engines

The SQL Server Query Optimizer is a cost-based optimizer. Each possible execution plan has an associated cost in terms of the amount of computing resources used. The Query Optimizer must analyze the possible plans and choose the one with the lowest estimated cost.

3) Classic Query Engine

Classic query engine handles all non-SQL queries but SQL query engine won’t handle logical files. CREATE Creates a new table, a view of a table, or other object in database ALTER Modifies an existing database object, such as a table. DROP Deletes an entire table, a view of a table or other object in the database.

4) SQL Query Engine

At a high level, a query engine is a piece of software that sits on top of a database or server and executes queries against data in that database or server to provide answers for users or applications. More specifically, a SQL query engine interprets SQL commands and language to access data in relational systems.