[MySQL]获取当月每一天

常用使用场景: 统计某个月(某个时间区间)内每一天的数据量 

   
   
  
  
 
   
 
    
 
     
 
    
 
    
 
     
 
      select 
      date_add( 
      curdate(), 
      interval( 
      cast(help_topic_id 
      as signed 
      integer) - 
      1) 
      day) 
      day 
     
 
    
 
   
 
    
 
     
 
    
 
    
 
     
 
      from mysql.help_topic 
     
 
    
 
   
 
    
 
     
 
    
 
    
 
     
 
      where help_topic_id < 
      day( 
      last_day( 
      curdate())) 
     
 
    
 
   
 
    
 
     
 
    
 
    
 
     
 
      order 
      by help_topic_id 
     
 
    
 
  
  
  
 
 

 

延伸用法: 获取一段时间内的每分钟

   
   
  
  
 
   
 
    
 
     
 
    
 
    
 
     
 
      set @stime = 
      str_to_date( 
      '2018-11-07 08:00', 
      '%Y-%m-%d %H:%i'); 
     
 
    
 
   
 
    
 
     
 
    
 
    
 
     
 
      set @etime = 
      str_to_date( 
      '2018-11-07 08:10', 
      '%Y-%m-%d %H:%i'); 
     
 
    
 
   
 
    
 
     
 
    
 
    
 
     
 
     
 
    
 
   
 
    
 
     
 
    
 
    
 
     
 
      select 
      date_add(@stime, 
      interval ( 
      cast(help_topic_id 
      as signed 
      integer) - 
      0) 
      minute) 
      minute 
     
 
    
 
   
 
    
 
     
 
    
 
    
 
     
 
      from mysql.help_topic 
     
 
    
 
   
 
    
 
     
 
    
 
    
 
     
 
      where help_topic_id <= 
      timestampdiff( 
      minute, @stime, @etime) 
     
 
    
 
   
 
    
 
     
 
    
 
    
 
     
 
      order 
      by help_topic_id 
     
 
    
 
  
  
  
 
 

 

顺便贴一下oracle的写法

   
   
  
  
 
   
 
    
 
     
 
    
 
    
 
     
 
      select trunc( 
      sysdate, 
      'MM') + 
      rownum - 
      1 
      day 
     
 
    
 
   
 
    
 
     
 
    
 
    
 
     
 
      from dual 
     
 
    
 
   
 
    
 
     
 
    
 
    
 
     
 
      connect 
      by 
      rownum <= to_number(to_char( 
      last_day( 
      sysdate), 
      'dd')) 
     
 
    
 
  
  
  
 
 

原文地址：https://blog.csdn.net/reeye_/article/details/83655477