Document MySQL PI() weird behaviour

[AnyhowStep]

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You know how one of the oft-touted rules for databases is to decouple data and representation? MySQL really ignores that rule for the PI() functions.

https://dev.mysql.com/doc/refman/8.0/en/mathematical-functions.html#function_pi

The default number of decimal places displayed is seven, but MySQL uses the full double-precision value internally.

So, PI() is 3.141593, but PI() + 0e0 is 3.141592653589793

And, PI() = 3.141592653589793 is TRUE because the displayed value and actual value are different.

However, database drivers don't generally know about this So, you might think a MySQL driver would return the "actual" value of PI() And not the "display" value of PI() Nope MySQL drivers return the "display" value of PI() !@#$%^&*

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This gives weird shit like,

SELECT PI(), PI() = 3.141592653589793, 3.141593 = 3.141592653589793;
> 3.141593, TRUE, FALSE

We also have,

SELECT PI() = 3.14159265358979
> TRUE

[AnyhowStep]

SELECT
PI() = 3.14159265358979,
3.14159265358979 = PI(),
PI() = 3.141592653589793,
3.141592653589793 = PI(),
3.14159265358979 = 3.141592653589793,
3.141592653589793 = 3.14159265358979, 

PI(),
3.14159265358979, 
3.141592653589793,

(PI()+0e0) = 3.14159265358979,
3.14159265358979 = (PI()+0e0),
(PI()+0e0) = 3.141592653589793,
3.141592653589793 = (PI()+0e0)
;

PI() = 3.14159265358979	3.14159265358979 = PI()	PI() = 3.141592653589793	3.141592653589793 = PI()	3.14159265358979 = 3.141592653589793	3.141592653589793 = 3.14159265358979	PI()	3.14159265358979	3.141592653589793	(PI()+0e0) = 3.14159265358979	3.14159265358979 = (PI()+0e0)	(PI()+0e0) = 3.141592653589793	3.141592653589793 = (PI()+0e0)
1	1	1	1	0	0	3.141593	3.14159265358979	3.141592653589793	0	0	1	1

[AnyhowStep]

WHY MYSQL WHY