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Bitwise use of SQL integer

Howard Watson
Ranch Hand

Joined: Jan 07, 2004
Posts: 56
Given JSP/servlet web-app:
Form with twelve checkboxes. I can store the state of each of the checkboxes as a bit set to 1 for box checked, in an SQL integer. I can retrieve the integer and loop through a shifted bit mask to reset the checkboxes in the form for editing.

The problem:
Ideally I'd like to perform a query like (SELECT (COUNT colBox) FROM tblBoxes WHERE colBox AND 3) would return a count of rows with bit 1 set in the integer.
The other choice is to select * colBox, && to a bitmask and count the good ones for 32 bitmasks thousands of times.

I'm sure there's an algorithm or query out there. Any ideas or references would be appreciated.
[ September 28, 2004: Message edited by: Howard Watson ]
Roberto Spier
Greenhorn

Joined: Sep 13, 2004
Posts: 7
Hello,

you haven't indicated what database you are using!

MySQL has a bitwise operator, and you'd do something like

SELECT * FROM table WHERE someBigIntField & 3;

hth
Roberto
Howard Watson
Ranch Hand

Joined: Jan 07, 2004
Posts: 56
Pervasive SQL 2000i. I think my "Ideally" is supported by some database vendors, and may not be supported by mine. I posted there too.
 
 
subject: Bitwise use of SQL integer