如何在(MYSQL和SQL Server)多列中搜索一个值，而不需要迭代/循环/游标？

SELECT * FROM table_name WHERE column1 = 'value' OR column2 = 'value' OR column3 = 'value';

SELECT * FROM table_name WHERE column1 = 'value' OR column2 = 'value' OR column3 = 'value';

SELECT * FROM table_name WHERE column1 = 'value'
UNION
SELECT * FROM table_name WHERE column2 = 'value'
UNION
SELECT * FROM table_name WHERE column3 = 'value';

SELECT * FROM table_name WHERE column1 = 'value'
UNION
SELECT * FROM table_name WHERE column2 = 'value'
UNION
SELECT * FROM table_name WHERE column3 = 'value';

SELECT * FROM table_name WHERE 
CASE 
    WHEN column1 = 'value' THEN 1
    WHEN column2 = 'value' THEN 1
    WHEN column3 = 'value' THEN 1
    ELSE 0
END = 1;

SELECT * FROM table_name WHERE 
CASE 
    WHEN column1 = 'value' THEN 1
    WHEN column2 = 'value' THEN 1
    WHEN column3 = 'value' THEN 1
    ELSE 0
END = 1;