If there's one official Marketo doc that needs some edits, it's the Marketo Field Limits by Field Type rundown.
Unfortunately, that article has incorrect info and some sins-of-omission.
Be warned: most of this post is (necessarily) dry and technical. But I always find competing claims to be interesting, almost regardless of the topic. Maybe you will too! Plus, even experienced high-level programmers (meaning languages other than C and C++) don't have this stuff at their fingertips, and may make implementation mistakes as a result. So if you're in a meeting and want to show some mild “data scientist” chops, these are good facts to drop.
I'll be adding to this series over time. To start off...
From the doc:
Values are limited to between -9223372036854775808 and 9223372036854775807.
This is technically correct.
Marketo stores Integer fields as signed 64-bit integers — signed meaning they can be negative or positive — so they fall into the range of -(2^63) to +(2^63-1). It can be useful to look at the high number in an easier-to-read way:
9 223 372 036 854 775 807
So 9 quintillion, 223 quadrillion, 372 trillion something.
If such a number seems unimaginably high in a martech scenario, I fully agree (though don't forget the ol' Grain of Rice parable).