Real to Decimal generate unexpected results

[devlead]

KQL query below

let dt = datatable (Int: int, String: string, Bool:bool, Double: double, Decimal: decimal)
[
    1, 'a', false, 0.0,  0.0,
    2, 'b', true,  1.2,  2.2,
    3, 'c', false, 1.1,  2.3,
    4, 'a', false, 0.0, '0.0',
    5, 'b', true,  1.2, '2.2',
    6, 'c', false, 1.1, '2.3',
    7, 'a', false, 0.0,  decimal(0.0),
    8, 'b', true,  1.2,  decimal(2.2),
    9, 'c', false, 1.1,  decimal(2.3),
];
dt

will generate a table containing these rows

Int	String	Bool	Double	Decimal
1	a	FALSE	0	0
2	b	TRUE	1.2	2.2000000000000002
3	c	FALSE	1.1	2.2999999999999998
4	a	FALSE	0	0
5	b	TRUE	1.2	2.2
6	c	FALSE	1.1	2.3
7	a	FALSE	0	0
8	b	TRUE	1.2	2.2
9	c	FALSE	1.1	2.3

Is this by design? If so, is it documented anywhere? I'm sure it can feel unexpected to some.

[mattwar]

Maybe it is due to the real value not having any implied precision, so it is converting to maximum precision, and you are seeing the floating-point representation. You should probably specify decimal data as decimal values.