![]() ![]() Products AS b Code language: SQL (Structured Query Language) ( sql ) To solve the problem, you need to use the CROSS JOIN clause.įirst, use the CROSS JOIN clause to get the combination of all stores and products: SELECT The query above could not answer this question. Now, what if you want to know also which store had no sales of a specific product. Products ON products.id = sales.product_idĬode language: SQL (Structured Query Language) ( sql ) This statement returns total sales for each store and product, you calculate the sales and group them by store and product as follows: SELECT INSERT INTO sales(store_id,product_id,quantity,sales_date)Ĭode language: SQL (Structured Query Language) ( sql ) MySQL CROSS JOIN example INSERT INTO products(product_name, price) Suppose that we have three products iPhone, iPad and Macbook Pro which are sold in two stores North and South. The table sales contains the products that sold in a particular store by quantity and date.įinally, insert data into the three tables.The table stores contains the stores where the products are sold.The table products contains the products master data that includes product id, product name, and sales price.Here are the descriptions of the three tables: ) Code language: SQL (Structured Query Language) ( sql ) Third, create new tables in the salesdb database: CREATE TABLE products ( ![]() Second, switch the current data to the new database salesdb: USE salesdb Code language: SQL (Structured Query Language) ( sql ) Setting up sample tablesįirst, create a new database salesdb: CREATE DATABASE IF NOT EXISTS salesdb Code language: SQL (Structured Query Language) ( sql ) Let’s set up some tables to demonstrate the CROSS JOIN clause. If you add a WHERE clause, in case table t1 and t2 has a relationship, the CROSS JOIN works like the INNER JOIN clause as shown in the following query: SELECT * FROM t1Ĭode language: SQL (Structured Query Language) ( sql ) MySQL CROSS JOIN clause examples In other words, it does not have the ON or USING clause. Note that different from the INNER JOIN, LEFT JOIN, and RIGHT JOIN clauses, the CROSS JOIN clause does not have a join predicate. The following illustrates the syntax of the CROSS JOIN clause that joins two tables t1 and t2: SELECT * FROM t1ĬROSS JOIN t2 Code language: SQL (Structured Query Language) ( sql ) In other words, the CROSS JOIN clause returns a Cartesian product of rows from the joined tables. The result set will include all rows from both tables, where each row is the combination of the row in the first table with the row in the second table. In general, if each table has n and m rows respectively, the result set will have nxm rows. Suppose you join two tables using the CROSS JOIN clause. Summary: in this tutorial, you will learn about the MySQL CROSS JOIN clause and how to use it more effectively. ![]()
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