checkbox value as binary bit in integer?

[mrgym]

Has anyone used binary bit positions to represent possible checkbox values?

I have an 'items' table. Each item can be 1 or more types ( wide, thin, etc). The usual SQL solution to this is that I would create a table which represents the types (one->many relationship). Instead, I wonder whether a binary int field would work.

binary value type
00000001 wide
00000010 thin
00000100 smooth

this would save join overhead.

Is this approach sane??

[Anon]

I see many IF statements in your future if you go that route.

[mrgym]

Example converting binary value to array of string values.

$definition = array( 1=> 'category 0',
2=>'category 1',
4=>'category 2',
8=>'category 3',
16=>'category 4',
32=>'category 5',
64=>'category 6',
128=>'category 7',
256=>'category 8',
512=>'category 9'
);// on to the limit of a 32-bit integer

$category_array[ ] = "";

$category = (int) 3;
$binarycategory = sprintf("%08s",DecBin($category));

print("Category value in the database:$category ($binarycategory) <br>");

for($shifter=1;$shifter<=512;$shifter=$shifter<<1) {

$binaryshifter = sprintf("%08s",DecBin($shifter));
print("tested against shifter bit value:$shifter&nbsp;&nbsp;($binaryshifter)&nbsp;&nbsp;-->&nbsp;&nbsp;");
($category & $shifter)?print("This is a $definition[$shifter]<br>"):print("This is NOT a $definition[$shifter]<br>");

}

OUTPUT:

Category value in the database:3 (00000011)
tested against shifter bit value:1 (00000001) --> This is a category 0
tested against shifter bit value:2 (00000010) --> This is a category 1
tested against shifter bit value:4 (00000100) --> This is NOT a category 2
tested against shifter bit value:8 (00001000) --> This is NOT a category 3
tested against shifter bit value:16 (00010000) --> This is NOT a category 4
tested against shifter bit value:32 (00100000) --> This is NOT a category 5
tested against shifter bit value:64 (01000000) --> This is NOT a category 6
tested against shifter bit value:128 (10000000) --> This is NOT a category 7
tested against shifter bit value:256 (100000000) --> This is NOT a category 8
tested against shifter bit value:512 (1000000000) --> This is NOT a category 9