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👐 Exercises

Time to get some practice with the concepts you've learned! Try to answer the following questions to the best of your ability. Feel free to reference the slides and notes you've taken during the lesson.

No cheating! Try to look at the answer only after you give it a try.

Try adding fuzzy search to your application so it can find the correct books, even if the user makes a typo.

tip

Remember the fuzzy parameter of the text operator? This is where you'd use it.

Answer
public async searchBooks(query: string): Promise<Book[]> {
  const aggregationPipeline = [
      {
          $search: {
              index: 'fulltextsearch',
              text: {
                  query,
                  path: ['title', 'authors.name', 'genres'],
                  fuzzy: {
                    maxEdits: 2
                  }
              }
          }
      }
  ];
  const books = await collections?.books?.aggregate(aggregationPipeline).toArray() as Book[];
  return books;
}

Promote the books of the month​

The marketing team has decided that they want to promote the books of the month. They want to show these books first in the search results. How would you do this?

tip

You'll need to use the compound operator with multiple operators here. There is a bookOfTheMonth boolean field on some of the books that you could use.

Answer
public async searchBooks(query: string): Promise<Book[]> {
    const aggregationPipeline = [
        {
          $search: {
            "index": "fulltextsearch",
            "compound": {
              "must": [
                {
                  "text": {
                    query,
                    "path": ["title", "authors.name", "genres"],
                    fuzzy: {
                      maxEdits: 2
                    }
                  }
                }
              ],
              "should": [
                {
                  "equals": {
                    "value": true,
                    "path": "bookOfTheMonth",
                    "score": {
                      "boost": { value: 10 }
                    }
                  }
                }
              ]
            }
          }
        }
      ];
    const books = await collections?.books?.aggregate(aggregationPipeline).toArray() as Book[];
    return books;
}