how to use join table code example

Example 1: how to join tables in sql

JOINING 2 Tables in sql

SELECT X.Column_Name , Y.Column_Name2
FROM TABLES1_NAME X 
INNER JOIN TABLES2_NAME Y ON X.Primary_key = Y.Foreign_key;


--FOR EXAMPLE
--GET THE FIRST_NAME AND JOB_TITLE
--USE EMPLOYEES AND JOBS TABLE
--THE RELATIONSHIP IS JOB_ID

SELECT E.FIRST_NAME , J.JOB_TITLE
FROM EMPLOYEES E
INNER JOIN JOBS J ON J.JOB_ID = E.JOB_ID;

Example 2: 3 joins in sql

SELECT e.FIRST_NAME ,     -- coming from EMPLOYEES table
			 d.DEPARTMENT_NAME ,-- coming from DEPARTMENTS table
			 l.CITY ,           -- coming from LOCATIONS table
			 c.COUNTRY_NAME ,   -- coming from COUNTRIES table
			 r.REGION_NAME      -- coming from REGIONS table
FROM EMPLOYEES e 
	INNER JOIN DEPARTMENTS d on e.DEPARTMENT_ID = d.DEPARTMENT_ID
	INNER JOIN LOCATIONS l   on l.LOCATION_ID   = d.LOCATION_ID
	INNER JOIN COUNTRIES c   on l.COUNTRY_ID    = c.COUNTRY_ID
	INNER JOIN REGIONS r     on c.REGION_ID     = r.REGION_ID ;

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Sql Example