How to add array to a existing document

Below is my snippet in test bucket,
{
“x”: “a”,
“b”: “24-dec-2016”,
“v”: “c”,
}

I am trying to add a new array. How do i do it?

My array is “ar”: [
{
“c1”: “at”,
“b1”: “t”,
}
]

So the output would be,

{
“x”: “a”,
“b”: “24-dec-2016”,
“ar”: [
{
“c1”: “at”,
“b1”: “t”,
}
]
“v”: “c”,
}.

You an use UPDATE as following

UPDATE test SET ar = [{"c1":"at","b1":"t"}] WHERE <some condition >;

Thanks, It worked.! Will come back with any other issues.!