UPDATE ACT_BlockNum SET CreateTime = DATE_ADD(CreateTime, INTERVAL 1 DAY);

UPDATE ACT_BlockNum SET CreateTime = DATE_ADD(CreateTime, INTERVAL -1 DAY);

 SELECT IFNULL(SUM(Num),0) from DPEvent.ACT_BlockNum where CreateTime BETWEEN #startTime# AND #endTime#;
MYSQL IFNULL(expr1,expr2)

update @A 
set c1=b.c1 ,c2=b.c2,c3=b.c3
from @A a,@B b where a.id=2 and b.id=6
update A
　　set (A.a2,A.a3) =(select B.b2,b.b3
　　from B
　　where B.b1= A.a1 and A.a3=100
　　)