what is inner join and outer join. differnce between both

Question

Satyapriya Nayak · Answer

Hi Selvi Please refer the below links http://www.programmerinterview.com/index.php/database-sql/inner-vs-outer-joins/ http://www.firebirdfaq.org/faq93/ Thanks

Chintan Rathod · Answer

Hi Selvi Inner Join =================== The INNER JOIN keyword return rows when there is at least one match in both tables. Syntax : SELECT column_name(s) FROM table_name1 INNER JOIN table_name2 ON table_name1.column_name=table_name2.column_name Person Table : Order Table : Example : SELECT Persons.LastName Persons.FirstName Orders.OrderNo FROM Persons INNER JOIN Orders ON Persons.P_Id=Orders.P_Id ORDER BY Persons.LastName Output : ======================= Outer Join ======================= The LEFT JOIN keyword returns all rows from the left table (table_name1) even if there are no matches in the right table (table_name2). The result set of a left outer join includes all the rows from the left table specified in the LEFT OUTER clause not just the ones in which the joined columns match. When a row in the left table has no matching rows in the right table the associated result set row contains null values for all select list columns coming from the right table. Syntax : SELECT column_name(s) FROM table_name1 LEFT JOIN table_name2 ON table_name1.column_name=table_name2.column_name Person Table Orders Table Example SELECT Persons.LastName Persons.FirstName Orders.OrderNo FROM Persons LEFT JOIN Orders ON Persons.P_Id=Orders.P_Id ORDER BY Persons.LastName Output Thanks & Regards ----------------- Chintan Rathod

what is inner join and outer join., differnce between both