2014-05-16 21 views
0

是否有可能從user表中返回隨機選擇的行,並將頭包含爲第一行?在SQL我目前所面對的只是返回5個隨機行(不一定是頭部)是否可以按ORDER BY RAND()限制但包含標題?

SELECT 
    'id', 
    'name' 
UNION ALL SELECT 
    id, 
    name 

INTO OUTFILE 'example.txt' 
    FIELDS TERMINATED BY ' , ' ENCLOSED BY '"' ESCAPED BY '\\' LINES TERMINATED BY '\r\n' 

FROM 
    users 

ORDER BY RAND() LIMIT 5 

回答

2

試試這個


SELECT 'id','name' 
UNION ALL 
Select a.* from(
    SELECT id, name 
    FROM users 
    ORDER BY RAND() LIMIT 5 
)a 
INTO OUTFILE 'example.txt' FIELDS TERMINATED BY ',' ENCLOSED BY '"' ESCAPED BY '\\' LINES TERMINATED BY '\r\n';