SELECT
        CASE
            WHEN performance_score = "90-day meets"             THEN 0
            WHEN performance_score = "PIP"                      THEN 1
            WHEN performance_score = "Needs Improvement"        THEN 2
            WHEN performance_score = "Fully Meets"              THEN 3
            WHEN performance_score = "Exceeds"                  THEN 4
            WHEN performance_score = "Exceptional"              THEN 5
            WHEN performance_score = "N/A- too early to review" THEN 9
            ELSE NULL
        END AS perf_scoreid,
        performance_score 
    FROM production_staff

    SELECT 
        perf_scoreid_dict.perf_scoreid, 
        production_staff.performance_score
    FROM  production_staff
    LEFT JOIN (
        SELECT DISTINCT 
            perf_scoreid, 
            performance_score
        FROM hr_dataset
        ORDER BY perf_scoreid) AS perf_scoreid_dict
    ON production_staff.performance_score = perf_scoreid_dict.performance_score