如何在Mysql查询中选择随机ID

Question

SELECT e.ent_seq, 
     GROUP_CONCAT(DISTINCT kei.keb SEPARATOR'; ')AS kebs, 
     GROUP_CONCAT(DISTINCT rei.reb SEPARATOR '; ') AS rebs, 
     GROUP_CONCAT(DISTINCT sei.mean SEPARATOR '; ') AS means, 
FROM entry e 
    LEFT JOIN k_ele kei ON e.entry = kei.entry 
    LEFT JOIN r_ele rei ON e.entry = rei.entry 
    LEFT JOIN sense se ON e.entry = se.entry 
    LEFT JOIN s_gloss_eng sei ON se.SID = sei.SID 
WHERE mn_null = 1 
GROUP BY e.entry 

如何随机选择e.entry？ e.entry是一个int。

Answer 1

您可以使用此解决方案 -

SELECT e.ent_seq, 
     GROUP_CONCAT(DISTINCT kei.keb SEPARATOR'; ')AS kebs, 
     GROUP_CONCAT(DISTINCT rei.reb SEPARATOR '; ') AS rebs, 
     GROUP_CONCAT(DISTINCT sei.mean SEPARATOR '; ') AS means, 
FROM (SELECT * FROM entry ORDER BY RAND() LIMIT 1) e 
    LEFT JOIN k_ele kei ON e.entry = kei.entry 
    LEFT JOIN r_ele rei ON e.entry = rei.entry 
    LEFT JOIN sense se ON e.entry = se.entry 
    LEFT JOIN s_gloss_eng sei ON se.SID = sei.SID 
WHERE mn_null = 1 
GROUP BY e.entry 

添加条件WHERE mn_null = 1到e表的别名，如果mn_null从entry表中的字段。

Answer 2

SELECT e.ent_seq, 
    GROUP_CONCAT(DISTINCT kei.keb SEPARATOR'; ')AS kebs, 
    GROUP_CONCAT(DISTINCT rei.reb SEPARATOR '; ') AS rebs, 
    GROUP_CONCAT(DISTINCT sei.mean SEPARATOR '; ') AS means 

FROM entry e 

LEFT JOIN k_ele kei ON e.entry = kei.entry 
LEFT JOIN r_ele rei ON e.entry = rei.entry 
LEFT JOIN sense se ON e.entry = se.entry 
LEFT JOIN s_gloss_eng sei ON se.SID = sei.SID 

WHERE e.ent_seq IN (SELECT jt5.jlpt5_seq FROM jlptn5 jt5 
        WHERE jt5.jlpt5_null = 0 
        ORDER BY RAND()) 
GROUP BY e.entry  
ORDER BY RAND() 
LIMIT 20