Bitwise operators in dgraph?

Very simple question – does dgraph support bitwise operators? Something like

@filter(gt(val(predicate & 8), 0))

The above, obviously, does not work, hence the question.

We have this

Thanks Michel! But I’m referring to bitwise operators (&, |) rather than logic operands (&&, ||). It’s probably not necessary anyway.

In fact, maybe you can suggest something better: it’s an old problem of storing a value for days of week. Back in the day we did this using bitwise operators. Monday = 1, Tuesday = 2, Wednesday = 4 etc. so a value for “Monday, Tuesday and Friday” would be 1 + 2 + 16 = 19.

Then in a search, you could have ‘daysOfWeek & 12 > 0’ in the ‘WHERE’ clause to see if days of Week included Wednesday or Thursday, for example.

You might tell me I should just have it stored in a node with each day of the week being a boolean, but there are advantages to having the days of week value be stored in a single variable rather than an edge to a whole new node.

To keep things as a single variable I can use a string (“MonTueFri”), then do a regex search on that string in the searches. Is that a stupid solution?

You could do the regexp solution. You could also just use OR operators, to say eq(dayofweek, "mon") || eq(dayofweek, "tue") || ..., etc.

Dgraph also has math operators, which support a pow function. You could try that to raise the days of week by 2, i.e. 2^dayofweek, and then check if the final output is as you expect it to be, by using an == operator in math again.

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