Mysql查询中如何选择随机ID

如何随机选择e.entry？e、 条目是一个整数。

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 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

---

如果

mn\u null

是

entry

表中的一个字段，则将条件

中mn\u null=1

添加到

e

表别名。

如果table

entry

为big，则速度会非常慢是的，此解决方案对于大型表来说速度较慢，但很容易理解。还有其他的解决方案，所有这些解决方案都可以以相同的方式应用于此查询。。。

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

 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