does worker use TCP for D1 or HTTP? like does it count as an outgoing request?

SELECT *
    FROM categories
    JOIN images_categories ON categories.id = images_categories.category_id
    JOIN images ON images_categories.image_id = images.id;

SELECT *
    FROM categories
    JOIN images_categories ON categories.id = images_categories.category_id
    JOIN images ON images_categories.image_id = images.id;

    let result = await platform!.env.DB.prepare(
        `SELECT *
    FROM categories
    JOIN images_categories ON categories.id = images_categories.category_id
    JOIN images ON images_categories.image_id = images.id;
    `
    ).all();

    let result = await platform!.env.DB.prepare(
        `SELECT *
    FROM categories
    JOIN images_categories ON categories.id = images_categories.category_id
    JOIN images ON images_categories.image_id = images.id;
    `
    ).all();

CREATE INDEX post_posted_retry_idx ON post (posted, retry);

CREATE INDEX post_posted_retry_idx ON post (posted, retry);

Error: D1_ERROR: FOREIGN KEY constraint failed
      at D1Database._sendOrThrow (cloudflare-internal:d1-api:66:19)

Error: D1_ERROR: FOREIGN KEY constraint failed
      at D1Database._sendOrThrow (cloudflare-internal:d1-api:66:19)