aggs101 - match, project

  var pipeline = [
    {
      $match: {
        "imdb.rating": { $gte: 7 },
        genres: { $nin: [ "Crime", "Horror" ] } ,
        rated: { $in: ["PG", "G" ] },
        languages: { $all: [ "English", "Japanese" ] }
      }
    }
  ]

db.movies_sample.aggregate(pipeline)


  var pipeline = [
    {
      $match: {
        "imdb.rating": { $gte: 7 },
        genres: { $nin: [ "Crime", "Horror" ] } ,
        rated: { $in: ["PG", "G" ] },
        languages: { $all: [ "English", "Japanese" ] }
      }
    },
    {
      $project: { "_id": 0, "title": 1, "rated": 1 }
    }
  ]

  var pipeline = [
    {
      $match: {
        title: {
          $type: "string"
        }
      }
    },
    {
      $project: {
        title: { $split: ["$title", " "] },
        _id: 0
      }
    },
    {
      $match: {
        title: { $size: 1 }
      }
    }
  ]


var pipeline = [
  {
    $match: {
      cast: { $elemMatch: { $exists: true } },
      directors: { $elemMatch: { $exists: true } },
      writers: { $elemMatch: { $exists: true } }
    }
  },
  {
  $project: {
    _id: 0,
    cast: 1,
    directors: 1,
    writers: {
        $map: {
          input: "$writers",
          as: "writer",
          in: {
            $arrayElemAt: [
              { $split: ["$$writer", " ("] }, 0
            ]
          }
        }
      }
    }
  },
  {
    $project: {
      labor_of_love: {
        $gt: [ { $size: { $setIntersection: ["$cast", "$directors", "$writers"] } }, 0 ]
      }
    }
  },
  {
    $match: { labor_of_love: true }
  },
  {
    $count: "labors of love"
  }
]