查找两个CASE语句的总和-(如何使用CASE表达式或横向连接

SELECT
    (CASE
        WHEN condition1 THEN value1
        WHEN condition2 THEN value2
        ...
        ELSE default_value
    END)
    +
    (CASE
        WHEN condition3 THEN value3
        WHEN condition4 THEN value4
        ...
        ELSE default_value
    END)
    AS sum_result
FROM your_table;

SELECT
    sum_result
FROM
    (SELECT
        value1 + value2 AS sum_result
    FROM your_table
    WHERE condition1 OR condition2) AS result1
CROSS JOIN
    (SELECT
        value3 + value4 AS sum_result
    FROM your_table
    WHERE condition3 OR condition4) AS result2;