Visual Studio GetHashCode（）的默认实现

Question

Visual Studio GetHashCode（）的默认实现：

SELECT 
    employee_id,
    project_id,
    start_date,
    end_date
FROM (
    SELECT
        *,
        COUNT(*) OVER (PARTITION BY employee_id, project_id, gs)
    FROM
       emp_diff, generate_series(date_trunc('month', start_date), date_trunc('month', end_date) , interval '1 month') gs
) s
WHERE count >= 2

为什么要将“ 2108858624”添加到ID中以进行GetHashCode计算？

视频：（Gif）