Select with bitwise and 1

[Jocsta]

I am looking for a way to "mask" bits using an AND in a select statement, or equivalent.
I need to replicate a select statement we have on SQLServer, that strips of the top bits of a number and returns the max value without them e.g. :-

select max(cast(entity_id as bigint) & 0x0ffff) from entity;

Only keeping the bottom X bits of the value in the column, where the entity_id column is a "number(16,0)". I just cant find the way to do it in Oracle tho...

Thanks,
JOC

 

[taupirho]

Check out the BITAND operator


In order to understand recursion, you must first understand recursion.

 

[Jocsta]

Thanks taupirho, that is exactly what I needed....
I had come across it while searching, but in all the examples I saw or it it was like "bitand(5,3) would return 1" etc, or it involved RAW stuff, so I (wrongly) assumed it was a PL/SQL thing and kinda discounted it without trying it.

I feel stupid now... thanks again.