Sequelize quesion

[real briar]

I want to find all items with category. But category can be undefined which means it should find all items

And I don't want to do it like this

Is there any way to make it in one query without this if else ?

[ancient echo]

Hi, i don't d answer to your question but can u explain these lines what they will do?
Like what are square brackets and percentages..?