Does the result change if we JOIN tables in a different order?


In the context of this exercise, does the result change if we JOIN tables in a different order?


No, when applying JOIN, also known as INNER JOIN, the data is joined on wherever there are matching values on a certain column specified by the ON clause, and regardless of the table order in the JOIN, the result should be the same. So whether you do
plays JOIN songs
songs JOIN plays
the results would be the same.

The only difference would be the order that the columns and rows appear in the result set, which will follow the order of the first, or left, table, but which can be easily modified so that there is no difference, such as by using an ORDER BY clause.


When will this be different? Left join? Then what should we do when we use left join?

And how about the information mentioned in primary key and foreign key part?
In that lesson, it metioned that we should join as below:

FROM (table with primary key)
JOIN (table with foreign key)
ON …

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I believe the response by jephos249 is incorrect. There is a difference in the presentation of the data if you change the order of the JOIN.

If you write the code like this:
plays JOIN songs
They are arranged by date

if you write the code:
songs JOIN plays

then the data is arranged by song.
then the songs are listed one after the other showing which user played each song before moving on to the next song.

Right, I just tested it