the hole explanation is:
I modified your select a bitt get a result for the random() function
sqlite> select b,a, b & a from (select random() as b, 65535 as a);
-3252060536130257049|65535|48999
So I got these results
b = -3252060536130257049 in decimal form
b = 1101001011011110010111000010110000101011111000111011111101100111 in binary
a = 65535 in decimal
a = 1111111111111111 in binary
b & a = 48999 in decimal
b & a = 1011111101100111 result in binary
The explanation is the AND operator takes the random() number witch is a
fraction
between 0 and 1 and compares all the bits to all the bits of the number 65535
and creates a result it sort of mutiplying a fraction with 65535
and the result is a number between 0 and 65534
AND : &
A bitwise AND takes two binary representations of equal length and performs the
logical
AND operation on each pair of corresponding bits.
In each pair, the result is 1 if the first bit is 1 AND the second bit is 1.
Otherwise, the result is 0.
For example:
0101 (decimal 5)
AND 0011 (decimal 3)
= 0001 (decimal 1)
In the C programming
1101001011011110010111000010110000101011111000111011111101100111
0000000000000000000000000000000000000000000000001111111111111111
================================================================
0000000000000000000000000000000000000000000000001011111101100111
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