--Задача 1211
SELECT
    query_name,
    ROUND(AVG(rating * 1.0 / position), 2) AS quality,
    ROUND(AVG(CASE WHEN rating < 3 THEN 1 ELSE 0 END) * 100,2) AS poor_query_percentage
FROM Queries
GROUP BY query_name;

--Задача 1193
SELECT
    TO_CHAR(trans_date, 'YYYY-MM') AS month,
    country,
    COUNT(*) AS trans_count,
    SUM(CASE WHEN state = 'approved' THEN 1 ELSE 0 END) AS approved_count,
    SUM(amount) AS trans_total_amount,
    SUM(CASE WHEN state = 'approved' THEN amount ELSE 0 END) AS approved_total_amount
FROM Transactions
GROUP BY
    TO_CHAR(trans_date, 'YYYY-MM'),
    country;