It seems that "$in" operator mechanics is a little broken in that filtered results appear to be missing 1-2 matches depending on the contents of the "$in" array. Screenshots and sample bot are attached. Note: I've only tested it with strings and a limited table size. https://cdn.discordapp.com/attachments/1227622753406812200/1227622753507479652/witty-seahorse_-_2024_Apr_10.bpz?ex=662913c8&is=66169ec8&hm=b3ade68fc31fd5ef0413595df69fc5ced4175a33505657f7a470ee29b7c9aa6a& https://cdn.discordapp.com/attachments/1227622753406812200/1227622753981694065/image.png?ex=662913c8&is=66169ec8&hm=bd2cd377d373b0c149060074bdbfc54b1ad854a10e469d1d2f394e7496b433e7&

@limited-gpu-21450 I can confirm this is a known bug on our side – a fix is expected in the new few days. Here's a workaround in the meantime:

// Doesn't work (bug)
{
    myCol: { $in: ["A", "B"] }
}

// Works fine
{
    $or: [
        { myCol: "A" },
        { myCol: "B" }
    ]
}