精妙的SQL语句收藏

• 说明：复制表(只复制结构,源表名：a 新表名：b)
  select * into b from a where 1<>1
  
• 说明：拷贝表(拷贝数据,源表名：a 目标表名：b)
  insert into b(a, b, c) select d,e,f from b;
  

• 说明：日程安排提前五分钟提醒
  select * from 日程安排 where datediff('minute',f开始时间,getdate())>5
  
• 说明：两张关联表，删除主表中已经在副表中没有的信息
  delete from info where not exists ( select * from infobz where info.infid=infobz.infid )
  

• 说明：清除表中重复的记录(PriKey为递增值主键,key为判断相同记录的标准)
  Delete From B Where B.PriKey In(Select B.PriKey from B As s1 Where B.PriKey not in (Select max(B.PriKey) from B As s2 Where s1.key=s2.key))