I can't recall from my DB knowledge if SQL supports nested boolean logic such as follows:
SELECT * FROM table WHERE col1='x' AND (col2='y' OR col3='z')
If you're having troubel wrapping your brain around that, another example of this logic would be
if(X && (y || z))
{
...
}
So yeah.. is that supported with SQL? How would I do something like that with, say, subqueries?