The following shows the output of the query above: ORDER BY sales DESC LIMIT 5) top5products2003Ĭode language: SQL (Structured Query Language) ( sql ) You can use the result of this query as a derived table and join it with the products table as follows: SELECT ORDER BY sales DESC LIMIT 5 Code language: SQL (Structured Query Language) ( sql ) WHERE YEAR(shippedDate) = 2003 GROUP BY productCode ROUND( SUM(quantityOrdered * priceEach)) sales The following query gets the top five products by sales revenue in 2003 from the orders and orderdetails tables in the sample database: SELECT The following illustrates the syntax of a query that uses a derived table: SELECTĭerived_table_name.c1 > 0 Code language: SQL (Structured Query Language) ( sql ) A simple MySQL derived table example If a derived table does not have an alias, MySQL will issue the following error: Every derived table must have its own alias. Unlike a subquery, a derived table must have an alias so that you can reference its name later in the query. Note that a stand-alone subquery is a subquery that can execute independently of the outer query. The following illustrates a query that uses a derived table: When a stand-alone subquery is used in the FROM clause of a SELECT statement, it is also called a derived table. The term derived table and subquery is often used interchangeably. A derived table is similar to a temporary table, but using a derived table in the SELECT statement is much simpler than a temporary table because it does not require creating the temporary table. Introduction to MySQL derived tablesĪ derived table is a virtual table returned from a SELECT statement. Summary: in this tutorial, you will learn about the MySQL derived tables and how to use them to simplify complex queries.
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