MySql【Insert Select Not Exist】判断记录再添加值的方案

INSERT INTO content (
    detail,
    status,
    beginTime,
    endTime)
SELECT
    @detail,
    1,
    NULL,
    NULL
FROM DUAL
    WHERE NOT EXISTS(
        SELECT contentId
        FROM content
        WHERE detail=@detail); 

INSERT INTO table(column1,column2,column3 ...columnN)
SELECT value1,value2,value3 ...valueN
FROM dual
WHERE NOT EXISTS(
      SELECT *
      FROM table
      WHERE value = ?
);