Re: % Negation Character
- From: "Andrew Kerber" <andrew.kerber@xxxxxxxxx>
- To: citlali.guerrero@xxxxxx
- Date: Mon, 18 Jun 2007 14:40:27 -0500
As an aside, I am really curious why you would want to do bitwise functions against columns in an Oracle database? Its not like you're working in assembler code where the functionality is needed. On 6/18/07, Guerrero, Citlali (GE, Corporate, consultant) < citlali.guerrero@xxxxxx> wrote:
Hi Mark, Thank you so m uch for your reply it was really helpful since I'm starting on Oracle =) also many thanks to you Nigel your reply was also very helpful and clear to me =), thank you all for your help =) , if any of you had questions about Perl I can help and I hope help also with Oracle I'll do my best. Thank you¡¡¡¡¡¡¡ Warn Regards, Citlali Bobak, Mark escribió: Hi Citlali, Unforetunately, AskTom, which has some great examples, seems to be down at the moment. However, I don't think you want to use the UTL_RAW stuff. There is the bitand() function, which is built-in to Oracle, and which is now documented, since 9i, I think. From that, you can build a simple bitor(): CREATE OR replace FUNCTION bitor( x IN NUMBER, y IN NUMBER ) RETURN NUMBER AS BEGIN RETURN x + y - bitand(x,y); END; / And, once you have both bitand() and bitor(), you can build a bitxor(): CREATE OR replace FUNCTION bitxor( x IN NUMBER, y IN NUMBER ) RETURN NUMBER AS BEGIN RETURN bitor(x,y) - bitand(x,y); END; / Finally, for One's complement, you can xor the number with all 1's. Here's the code for bitcomplement(): create or replace function bitcomplement(x in number, y in number) return number as begin return bitxor(x,power(2,y)-1); end; / So, you can do something like: SQL> select bitcomplement(2,4) from dual; BITCOMPLEMENT(2,4) ------------------ 13 Note that the second argument to bitcomplement is how "wide" the bitfield should be. In this case, it's 4, if you're expecting 13. Note that the value of the one's complement will depend on how many 1's you're xoring against. Finally, thanks to Connor McDonald for the bitor() and bitxor() functions. The bitcomplement() function is my own creation. -Mark *-- Mark J. Bobak* *Senior Database Administrator, System & Product Technologies* ProQuest 789 E. Eisenhower, Parkway, P.O. Box 1346 Ann Arbor MI 48106-1346 734.997.4059 or 800.521.0600 x 4059 *email@example.com* <mark.bobak@xxxxxxxxxxxxxxx> *www.proquest.com* <http://www.proquest.com/> *www.csa.com* <http://www.csa.com/> *ProQuest...*Start here. ------------------------------ *From:* oracle-l-bounce@xxxxxxxxxxxxx [ mailto:oracle-l-bounce@xxxxxxxxxxxxx <oracle-l-bounce@xxxxxxxxxxxxx>] *On Behalf Of *Guerrero, Citlali (GE, Corporate, consultant) *Sent:* Monday, June 18, 2007 11:07 AM *To:* Nigel Thomas *Cc:* oracle-l *Subject:* Re: % Negation Character Hi Nigel, Thanks for the tip, however, as you mention on your email, I'm facing some troubles with the data types, I mean if I perform: raw_value := utl_raw.cast_from_number('2'); -- This is equal to c103 and then I try to get the complement or negative value with this: select select utl_raw.bit_COMPLEMENT('c103') from dual; I get the value: UTL_RAW.BIT_COMPLEMENT('C103') --------------------------------- 3efc And when I try to perform this: SELECT utl_raw.cast_to_number('3efc') FROM dual I got the result: UTL_RAW.CAST_TO_NUMBER('3EFC') --------------------------------- -105 What I'm expecting is: 13 ... Do you know or have any clue about this??? I really appreciate the help Regards Citlali Nigel Thomas escribió: Citali > I'm migrating from Sybase to Oracle, on Sybase I had a function with > update XYZ > set flag = flag &~4589 You can use BITAND(arg1, arg2) - see the SQL reference for more information. Shame there's no BITOR to go with it... See also UTL_RAW package and functions BIT_AND, BIT_OR, BIT_XOR and BIT_COMPLEMENT. You just need to be careful with datatypes, I seem to remember. I played with UTL_RAW quite recently, but on a previous site so I don't have it to hand, sorry. HTH Regards Nigel -- http://www.freelists.org/webpage/oracle-l -- http://www.freelists.org/webpage/oracle-l
-- Andrew W. Kerber 'If at first you dont succeed, dont take up skydiving.'