面试题答案
一键面试[
{
$project: {
name: 1,
averageSalary: {
$round: ["$salary", 2]
},
skills: {
$map: {
input: "$skills",
in: {
$toUpper: {
$substrCP: ["$$this", 0, 1]
} + {
$substrCP: ["$$this", 1]
}
}
}
}
}
}
]