.and() issue

[TheMenethil]

Hello,

Here is what I have in my DB (for test purposes) :

const db = new Dexie('App');
db.version(1).stores({
    items: '++id,description,image,isDone'
});
await db.items.bulkAdd([
    { id: 1, description: "item n°1", image: "placeholder.jpg", isDone: "N" },
    { id: 2, description: "item n°2", image: "placeholder2.jpg", isDone: "Y" },
    { id: 3, description: "item n°3", image: "placeholder3.jpg", isDone: "N" }
    { id: 4, description: "item n°4", image: "placeholder4.jpg", isDone: "N" }
]);

I want to get a random item between the ones marked "N" in "isDone".

To do so, I wrote this :

async function search() {
    var count = await db.items.where("isDone").equals("N").count();

    var rand = Math.floor(Math.random() * count);

    var result = await db.items.where("isDone").equals("N").and(item => item.where('id').equals(rand));
    //result = await db.items.where("isDone").equals("N").and(.where('id').equals(3));
};

As you can see, I am struggling with the "and()" condition. I know I don't get something in it but the documentation for it is a bit short.

Thank you very much !

[dfahlander]

The doc page is indeed not very expressive.

The filter argument should be a callback that takes a database object (value) and returns true or false. Here's an example that might clarify the same intent as your snippet:

async function search() {
    var count = await db.items.where("isDone").equals("N").count();

    var rand = Math.floor(Math.random() * count);

    var result = await db.items
      .where("isDone").equals("N")
      .and(item => item.id === rand) // callback is plain function returning boolean
      .toArray(); // still need to do .toArray() at end

    return result;
}

[TheMenethil]

Thank you very much !
Have a great day !

[dfahlander]

The doc page for Collection.and() is updated.