Check out example codes for "sql join syntax". It will help you in understanding the concepts better.

Code Example 1

Suppose we are having three table named as 
Student_details
Attendance_details
Batch_details
And we have to apply join these three tables for fetching records

Example query:
select column_names
from Student_detail as s join Attendance_details as a on
s.s_id = a.s_id join Batch_details as b on 
s.s_id = b.s_id;

Here in the above example we implemented simple join but you change it with own join requirements.

Code Example 2

SELECT column-names  FROM table-name1 JOIN table-name2     ON column-name1 = column-name2 WHERE condition

Code Example 3

SELECT Orders.OrderID, Customers.CustomerName, Orders.OrderDate
FROM Orders
INNER JOIN Customers ON Orders.CustomerID=Customers.CustomerID;

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