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【DM版本】:7
【操作系统】：Windows
【CPU】:
【问题描述】*：SELECT
n.subject_label AS name,
x.topic AS topic,
x.num AS tabNum,
count( 1 ) AS fieldNum,
x.lvl AS type
FROM
( SELECT topic, count( 1 ) num, tab_id, lvl FROM pdi.pdi_meta_tab GROUP BY topic ORDER BY count( 1 ) DESC LIMIT 5 ) x
LEFT JOIN pdi.pdi_meta_tab_field f ON x.tab_id = f.tab_id
LEFT JOIN pdi.pdi_meta_subject n ON n.subject_name = x.topic

WHERE
(‘’ = ‘’ or x.lvl = ‘’ )

GROUP BY
f.tab_id

这个应该怎么改？