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09-20    ²¿ÃÅ1    100
09-20    ²¿ÃÅ2    200
09-20    ²¿ÃÅ3    300
09-19    ²¿ÃÅ2    400
09-19    ²¿ÃÅ4    500
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SQL code:
select * from yourTable a
where not exists (select 1 from yourTable where ÈÕÆÚ=a.ÈÕÆÚ and ÓªÒµ¶î>a.ÓªÒµ¶î);


SQL code:

select ²¿ÃÅ,sum(ÓªÒµ¶î) ×ÜÓªÒµ¶î
from ±íÃû
group by ²¿ÃÅ
order by ×ÜÓªÒµ¶î desc
limit 1;



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SQL code:
select a.*
from yourTable a inner join (select ÈÕÆÚ,max(ÓªÒµ¶î) as max_ÓªÒµ¶î from yourTable group by ÈÕÆÚ) b
on a.ÈÕÆÚ=b.ÈÕÆÚ and a.ÓªÒµ¶î=b.max_ÓªÒµ¶î


SQL code:

mysql> select * f


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if(mysql_real_connect(&mysql,"125.0.0.108","root","root","home",3306,NULL,0))

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now()

SQL code:

sqlÀïÊÇ£º
getdate()

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now()


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SQL code:
select now();

SQL code:
TODAY()
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SQL code:
select now();
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