{
    "queries": [
        {
            "query": "SELECT species, COUNT(*) AS n FROM iris GROUP BY species ORDER BY n DESC",
            "description": "Number of flowers recorded for each species."
        },
        {
            "query": "SELECT species, AVG(petal_length) AS avg_petal_length, AVG(petal_width) AS avg_petal_width FROM iris GROUP BY species ORDER BY avg_petal_length DESC",
            "description": "Average petal size for each species."
        },
        {
            "query": "SELECT MIN(sepal_length) AS min_len, MAX(sepal_length) AS max_len, AVG(sepal_length) AS avg_len FROM iris WHERE sepal_length IS NOT NULL",
            "description": "Smallest, largest and average sepal length across all flowers."
        },
        {
            "query": "SELECT * FROM iris WHERE species = 'virginica' ORDER BY petal_length DESC LIMIT 10",
            "description": "The ten virginica flowers with the longest petals."
        },
        {
            "query": "SELECT species, MAX(sepal_width) AS widest_sepal, MIN(sepal_width) AS narrowest_sepal FROM iris GROUP BY species ORDER BY widest_sepal DESC",
            "description": "Widest and narrowest sepals recorded for each species."
        },
        {
            "query": "SELECT species, COUNT(*) AS n FROM iris WHERE petal_length > 4 GROUP BY species ORDER BY n DESC",
            "description": "How many flowers per species have petals longer than 4."
        },
        {
            "query": "SELECT * FROM iris WHERE species = 'setosa' ORDER BY sepal_length DESC LIMIT 10",
            "description": "The ten setosa flowers with the longest sepals."
        },
        {
            "query": "SELECT species, ROUND(AVG(sepal_length / sepal_width), 2) AS avg_sepal_ratio FROM iris WHERE sepal_width IS NOT NULL AND sepal_width > 0 GROUP BY species ORDER BY avg_sepal_ratio DESC",
            "description": "Average sepal length-to-width ratio for each species."
        },
        {
            "query": "SELECT * FROM iris WHERE species = 'versicolor' AND petal_width IS NOT NULL ORDER BY petal_width DESC LIMIT 10",
            "description": "The ten versicolor flowers with the widest petals."
        }
    ]
}