SQL INNER JOIN keyword usage tutorial

SQL INNER JOIN keyword usage tutorial

When the keyword of inner join is returned, at least one row in the competition is returned.

SQL Syntax of INNER JOIN

SELECT column_name(s)FROM table_name1INNER JOIN table_name2 ON table_name1.column_name=table_name2.column_name

PS:Inner join is the same as JOIN.
 
Let's take a look at an example.
 

P_Id	LastName	FirstName	Address	City
1	Hansen	Ola	Timoteivn 10	Sandnes
2	Svendson	Tove	Borgvn 23	Sandnes
3	Pettersen	Kari	Storgt 20	Stavanger

 

Let's take a look at the orders table.

 

_ Id	OrderNo	P_Id
1	77895	3
2	44678	3
3	22456	1
4	24562	1
5	34764	15

 

Now, we want to list any commands of all people.

We use the following SELECT statement:

 

SELECT Persons.LastName, Persons.FirstName, Orders.OrderNoFROM PersonsINNER JOIN OrdersON Persons.P_Id=Orders.P_IdORDER BY Persons.LastName

LastName	FirstName	OrderNo
Hansen	Ola	22456
Hansen	Ola	24562
Pettersen	Kari	77895
Pettersen	Kari	44678

When the keyword of inner join orders is returned, at least one row in the competition is returned. If there are "orders" listed in "persons" that do not match ",
Will these rows be listed.