5_optimal_skills.sql

/*
Answer: What are the most optimal skills to learn (aka it's in high demand and a high-paying skill)?
- Identify skills in high demand and associated with high average salaries for Data Analyst roles
- Concentrates on remote positions with specified salaries
- Why? Targets skills that offer job security (high demand) and financial benefits (high salaries),
offering strategic insights for career development in data analysis
*/

WITH skills_demand AS (
    SELECT
        skills_dim.skill_id,
        skills_dim.skills,
        COUNT(skills_job_dim.job_id) AS demand_count
    FROM job_postings_fact
    INNER JOIN skills_job_dim ON job_postings_fact.job_id = skills_job_dim.job_id
    INNER JOIN skills_dim ON skills_job_dim.skill_id = skills_dim.skill_id
    WHERE
        job_title_short = 'Data Analyst' AND
        salary_year_avg IS NOT NULL AND
        job_work_from_home = TRUE
    GROUP BY 
        skills_dim.skill_id, skills_dim.skills
),

average_salary AS (
    SELECT
        skills_dim.skill_id,
        ROUND(AVG(salary_year_avg), 0) AS avg_salary
    FROM job_postings_fact
    INNER JOIN skills_job_dim ON job_postings_fact.job_id = skills_job_dim.job_id
    INNER JOIN skills_dim ON skills_job_dim.skill_id = skills_dim.skill_id
    WHERE
        job_title_short = 'Data Analyst' 
        AND salary_year_avg IS NOT NULL
        AND job_work_from_home = TRUE
    GROUP BY 
        skills_dim.skill_id
)

SELECT
    skills_demand.skill_id,
    skills_demand.skills,
    skills_demand.demand_count,
    average_salary.avg_salary
FROM
    skills_demand
INNER JOIN average_salary ON skills_demand.skill_id = average_salary.skill_id
WHERE
    demand_count > 10
ORDER BY
    avg_salary DESC,
    demand_count DESC    
LIMIT 25;


-- rewriting this query more concisely
SELECT
    skills_dim.skill_id,
    skills_dim. skills,
    COUNT(skills_job_dim.job_id) AS demand_count,
    ROUND(AVG(job_postings_fact.salary_year_avg), 0) AS avg_salary
FROM job_postings_fact
INNER JOIN skills_job_dim ON job_postings_fact.job_id = skills_job_dim.job_id
INNER JOIN skills_dim ON skills_job_dim. skill_id = skills_dim. skill_id
WHERE
    job_title_short = 'Data Analyst'
    AND salary_year_avg IS NOT NULL
    AND job_work_from_home = True
GROUP BY
    skills_dim.skill_id
HAVING
    COUNT(skills_job_dim.job_id) > 10
ORDER BY
    avg_salary DESC,
    demand_count DESC
LIMIT 25;