To find Apple's price today, we need to:
1. Generate a subquery to get the latest price data for Apple (AAPL) from the `price_data` table.
2. Ensure we get the most recent data by ordering by date in descending order and limiting the results to 1.
3. Include the fields for symbol, date, last closing price, and trading volume.
Now I will generate the query:
{
  "sql": "SELECT symbol, date, lastClosingPrice AS price, tradingVolume AS volume FROM `my_project.my_dataset.price_data` WHERE symbol = 'AAPL' ORDER BY date DESC LIMIT 1"
}