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mysql> select searchid,keywords,tids,count(keywords) as keywdnum from dz_searchindex where tids like '%,485226,%' and keywords !='' and keywords not like '%+%' group by keywords order by keywdnum desc limit 5;
Empty set (5.78 sec)
1.此select语句,若是评分能得几分(10分满)
2.此语句若性能不好,主要是因为那部分.
3.能若提高良好的解决办法.
4.若是不修改此SQL语句.能否从mysql配置参数和硬件方面提高性能.
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