Re: operators and bit field

Bruno, could you check that with explicity bitfield(n) values, please?


2/14/2003 1:37:03 PM, Bruno Wolff III <bruno@wolff.to> wrote:

>On Fri, Feb 14, 2003 at 11:12:15 -0800,
>  Dennis Gearon <gearond@cvc.net> wrote:
>> I haven't seen what operators can be applied to bit masks.
>
>It looks like & works:
>area=> select 3&6;
> ?column?
>----------
>        2
>(1 row)
>
>>
>> In particular, I am looking to use binary AND:
>>
>> I want to AND two bitmasks together and see:
>>
>>     A/ if the result has ANY bits set
>>     B/ what bits are set in the results.
>>
>> SELECT other_fields
>> FROM some_table
>> WHERE
>>       ( bitmask_8_columnA & bitmask_8_column B) = bitmask_8_patternONE
>>    OR ( bitmask_8_columnA & bitmask_8_column B) = bitmask_8_patternTWO
>> ;
>>
>> I may try to use a single char for one of the bit masks I need,
>> is it possible to store all 256 values into a varchar(1) using
>> escaped input?
>>
>> Is it possible to AND two varchars within a select and compare the result?
>>
>> SELECT other_fields
>> FROM some_table
>> WHERE ( varchar_1_columnA & varchar_1_columnB ) = 'single_escaped_char_string';
>>
>>
>>
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>