Western Governors University (WGU) ITEC2117 D427 Data Management - Applications Pre-Assessment Practice

An INNER JOIN combines rows from two or more tables based on a related column between them. It filters the result set to include only those rows where there is a match found between the specified columns of the joined tables. This means that if a row in the first table does not have a corresponding matching row in the second table (and vice versa), it will not appear in the results of the query. For instance, consider two tables: one containing customer information and another containing order details. If you perform an INNER JOIN on the customer ID, the resulting dataset will only include customers who have placed at least one order. Any customers without orders or orders without matching customers will be excluded. This filtering characteristic distinguishes INNER JOINs from other types of joins, such as LEFT JOINs or RIGHT JOINs, which include non-matching rows from one table. Thus, the INNER JOIN effectively highlights the intersections of the data from the participating tables by only presenting the rows where matches exist.