INNER JOIN
keyword selects records that have matching values in both tables.
Here is the sample of Engineer table
id |
fullname |
title |
department |
manager |
1 |
Eric Brown |
Software Engineer |
IT |
Frank Martin |
2 |
Brandon Hart |
DevOps Engineer |
IT |
Justin Martin |
3 |
Connor Langdon |
Software Engineer |
IT |
Lucas Scott |
Here is the sample of Certificate table
id |
engineerid |
certificatename |
certificatedate |
1 |
1 |
Docker Certified Associate |
2020-05-05 |
2 |
2 |
Certified Kubernetes Administrator |
2021-07-03 |
Here is the sample of Course table
Examples / Outputs
1SELECT e.id, e.fullname, c.certificatename
2FROM engineer AS e
3INNER JOIN certificate AS c
4ON e.Id=c.Engineerid;
engineerid |
fullname |
certificateName |
1 |
Eric Brown |
Docker Certified Associate |
2 |
Brandon Hart |
Certified Kubernetes Administrator |
Join more than two Tables
1SELECT e.id, e.fullname "Full Name",
2cert.certificatename "Certificate Name",
3co.coursename "Course Name"
4FROM engineer AS e
5INNER JOIN certificate AS cert ON e.Id=cert.engineerid
6INNER JOIN course as co ON co.certid=cert.id;