bitmasks are really handy way to express predicates without becoming overly verbose with parens and logical operators (AND and OR). Assume we have the following table.
| what | wanted |
|-------------|--------|
| need me too | 4 |
| alpha | 1 |
| beta | 2 |
with data as
(
select 'appears_in_both', 4 as wanted from dual
union all
select 'alpha', 1 as wanted from dual
union all
select 'beta', 2 as wanted from dual
)
...
Get "need me too" and "alpha" together
...
select *
from data
where bitand(wanted, 5) <> 0; -- (4 + 1)
Get "need me too" and "beta" together
...
select *
from data
where bitand(wanted, 6) <> 0; -- (4 + 2)
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