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SQL Project Planning

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  • Wisnu_D_Uzu
    2 months ago+ 0 comments
    WITH difference AS (
        SELECT 
            start_date, 
            end_date,
            @group := IF(@prev_end = start_date, @group, @group + 1) AS grp,
            @prev_end := end_date
        FROM projects, (SELECT @prev_end := NULL, @group := 0) vars
        ORDER BY 1
    )
    SELECT 
        MIN(start_date) AS start_date, 
        MAX(end_date) AS end_date
    FROM difference
    GROUP BY grp
    ORDER BY count(grp), 1;
    
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