Remko1981's comments

Remko1981 | 4 years ago | on: What's the strangest code you've seen a senior developer write? (2019)

What a lot of people do not realize is that they are making implicit inner joins because of the way they use the where clauses.

When you say 'where left join column = some value' you exclude all rows containing NULL in that column. In other words all rows that did not join in addition to rows which contain a NULL in the column.