Different types of languages deal with this “value” in diverse
ways. You can have a more comprehensive list of what
NULL can mean on this
website. What I like to think about NULL is
along the lines of invalid, as if some sort of garbage
is stored there. It doesn’t mean it’s empty, it’s just mean that
something is there, and it has no value to you.
Databases deal when storing this type in a similar way, PostgreSQL treats it as “unknown” while MySQL treats it as “no data“.
Both databases recommend using \N to represent
NULL values where import or exporting of data is
necessary.
When …
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