检索字段的唯一值

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import { MongoClient } from "mongodb";
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// Replace the uri string with your MongoDB deployment's connection string.
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const uri = "<connection string uri>";
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const client = new MongoClient(uri);
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async function run() {
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  try {
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    // Get the database and collection on which to run the operation
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    const database = client.db("sample_mflix");
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    const movies = database.collection("movies");
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    // Specify the document field to find distinct values for
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    const fieldName = "year";
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    // Specify an optional query document to narrow results
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    const query = { directors: "Barbra Streisand" };
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    // Execute the distinct operation
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    const distinctValues = await movies.distinct(fieldName, query);
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    // Print the result
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    console.log(distinctValues);
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  } finally {
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    await client.close();
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  }
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}
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run().catch(console.dir);

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import { MongoClient } from "mongodb";
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// Replace the uri string with your MongoDB deployment's connection string.
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const uri = "<connection string uri>";
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const client = new MongoClient(uri);
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interface Movie {
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  directors: string;
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  year: number;
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}
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async function run() {
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  try {
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    // define a database and collection on which to run the method
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    const database = client.db("sample_mflix");
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    const movies = database.collection<Movie>("movies");
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    const distinctValues = await movies.distinct("year", {
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      directors: "Barbra Streisand",
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    });
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    console.log(distinctValues);
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  } finally {
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    await client.close();
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  }
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}
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run().catch(console.dir);