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Welcome to your Convex functions directory!

Write your Convex functions here. See https://docs.convex.dev/using/writing-convex-functions for more.

A query function that takes two arguments looks like:

// myQueryFunction.js
import { query } from "./_generated/server";

export default query(async ({ db }, { first, second }) => {
  // Validate arguments here.
  if (typeof first !== "number" || first < 0) {
    throw new Error("First argument is not a non-negative number.");
  }
  if (typeof second !== "string" || second.length > 1000) {
    throw new Error("Second argument is not a string of length 1000 or less.");
  }

  // Query the database as many times as you need here.
  // See https://docs.convex.dev/using/database-queries to learn how to write queries.
  const documents = await db.query("tablename").collect();

  // Write arbitrary JavaScript here: filter, aggregate, build derived data,
  // remove non-public properties, or create new objects.
  return documents;
});

Using this query function in a React component looks like:

const data = useQuery("myQueryFunction", { first: 10, second: "hello" });

A mutation function looks like:

// myMutationFunction.js
import { mutation } from "./_generated/server";

export default mutation(async ({ db }, { first, second }) => {
  // Validate arguments here.
  if (typeof first !== "string" || typeof second !== "string") {
    throw new Error("Both arguments must be strings");
  }

  // Insert or modify documents in the database here.
  // Mutations can also read from the database like queries.
  const message = { body: first, author: second };
  const id = await db.insert("messages", message);

  // Optionally, return a value from your mutation.
  return await db.get(id);
});

Using this mutation function in a React component looks like:

const mutation = useMutation("myMutationFunction");
function handleButtonPress() {
  // fire and forget, the most common way to use mutations
  mutation({ first: "Hello!", second: "me" });
  // OR
  // use the result once the mutation has completed
  mutation({ first: "Hello!", second: "me" }).then((result) =>
    console.log(result)
  );
}

The Convex CLI is your friend. See everything it can do by running npx convex -h in your project root directory. To learn more, launch the docs with npx convex docs.