How Does SQL Process TOP, WHERE, and ORDER BY Clauses?

Execution Order of SQL Statement

The provided SQL statement involves three clauses: TOP, WHERE, and ORDER BY. The execution order of these clauses is determined by the logical processing order specified in the SELECT statement documentation.

1. FROM Clause:
   First, the query processor binds to the tables or views specified in the FROM clause, making them available to subsequent steps. In this case, the query selects from the Customer table (C).
2. WHERE Clause:
   Next, the WHERE clause filters the data by specified conditions. The query filters for customers with salaries greater than 10,000.
3. ORDER BY Clause:
   Finally, the ORDER BY clause sorts the result set in descending order based on customer salary. Only the top 5 results will be returned.

Note: It's important to note that the actual physical execution order may vary depending on the query processor. However, the logical processing order provides a framework for understanding when objects are made available to each clause.

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