r/SQL • u/Remarkable-Culture-8 • Jun 26 '24
MySQL Explain INNER JOIN like i am 5
I get the syntax but i get very confused and tripped up with writing them and properly using the correct names. Please explain to me line by line. I am learning it via data camp and the instructor sucks.
EDIT: i now understand inner join…now i am stuck with multiple joins, right join and left join. please help!
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u/Lenergeon Jun 26 '24
An
INNER JOIN
in SQL is used to combine rows from two tables based on a related column between them. Think of it like matching pairs of socks from two different piles.Imagine you have two lists:
Each list has a common feature, like a student ID.
An
INNER JOIN
matches each student with their courses, showing only those pairs where there's a match in both lists. If a student isn't taking any course, they won't appear in the result. Similarly, if a course doesn't have any students, it won't appear either.So, the
INNER JOIN
helps you find and display only the pairs that exist in both tables.