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You have been asked to support an investment firm by analyzing trends in high-growth companies. They are interested in understanding which industries are producing the highest valuations and the rate at which new high-value companies are emerging. Providing them with this information gives them a competitive insight as to industry trends and how they should structure their portfolio looking forward.

You have been given access to their unicorns database, which contains the following tables:

dates

ColumnDescription
company_idA unique ID for the company.
date_joinedThe date that the company became a unicorn.
year_foundedThe year that the company was founded.

funding

ColumnDescription
company_idA unique ID for the company.
valuationCompany value in US dollars.
fundingThe amount of funding raised in US dollars.
select_investorsA list of key investors in the company.

industries

ColumnDescription
company_idA unique ID for the company.
industryThe industry that the company operates in.

companies

ColumnDescription
company_idA unique ID for the company.
companyThe name of the company.
cityThe city where the company is headquartered.
countryThe country where the company is headquartered.
continentThe continent where the company is headquartered.

The output

Your query should return a table in the following format:

industryyearnum_unicornsaverage_valuation_billions
industry12021------
industry22020------
industry32019------
industry12021------
industry22020------
industry32019------
industry12021------
industry22020------
industry32019------

Where industry1, industry2, and industry3 are the three top-performing industries.

Spinner
DataFrameas
df
variable
WITH unicorns_2019_2021 AS (
    SELECT
        i.industry,
        EXTRACT(YEAR FROM d.date_joined) AS year
    FROM industries i
    JOIN dates d ON i.company_id = d.company_id
    WHERE EXTRACT(YEAR FROM d.date_joined) IN (2019, 2020, 2021)
),
top_3_industries AS (
    SELECT
        industry,
        COUNT(*) AS unicorn_count
    FROM unicorns_2019_2021
    GROUP BY industry
    ORDER BY unicorn_count DESC
    LIMIT 3
),
all_years AS (
    SELECT DISTINCT year FROM (
        SELECT 2019 AS year UNION ALL
        SELECT 2020 UNION ALL
        SELECT 2021
    ) y
),
industry_year_combinations AS (
    SELECT
        ti.industry,
        y.year
    FROM top_3_industries ti
    CROSS JOIN all_years y
),
industry_data AS (
    SELECT
        i.industry,
        EXTRACT(YEAR FROM d.date_joined) AS year,
        COUNT(*) AS num_unicorns,
        ROUND(SUM(f.valuation) / 1000000000.0 / COUNT(*), 2) AS avg_valuation_billions
    FROM industries i
    JOIN dates d ON i.company_id = d.company_id
    JOIN funding f ON i.company_id = f.company_id
    WHERE i.industry IN (SELECT industry FROM top_3_industries)
      AND EXTRACT(YEAR FROM d.date_joined) IN (2019, 2020, 2021)
    GROUP BY i.industry, year
)
SELECT
    c.industry,
    c.year,
    COALESCE(d.num_unicorns, 0) AS num_unicorns,
    COALESCE(d.avg_valuation_billions, 0) AS average_valuation_billions
FROM industry_year_combinations c
LEFT JOIN industry_data d
    ON c.industry = d.industry AND c.year = d.year
ORDER BY c.year DESC, num_unicorns DESC;