MySQL get time

# The first day of that year ：  
SELECT DATE_SUB(CURDATE(),INTERVAL dayofyear(now())-1 DAY);  
  
# The last day of the year ：  
SELECT concat(YEAR(now()),'-12-31');    
  
# At present week The first day of ：    
select date_sub(curdate(),INTERVAL WEEKDAY(curdate()) + 1 DAY);  
  
# At present week Last day ：    
select date_sub(curdate(),INTERVAL WEEKDAY(curdate()) - 5 DAY);  
  
# Previous one week The first day of ：    
select date_sub(curdate(),INTERVAL WEEKDAY(curdate()) + 8 DAY);  
  
# Previous one week Last day ：    
select date_sub(curdate(),INTERVAL WEEKDAY(curdate()) + 2 DAY);  
  
# The first two week The first day of ：    
select date_sub(curdate(),INTERVAL WEEKDAY(curdate()) + 15 DAY);  
  
# The first two week Last day ：    
select date_sub(curdate(),INTERVAL WEEKDAY(curdate()) + 9 DAY);  
  
# At present month The first day of ：    
SELECT concat(date_format(LAST_DAY(now()),'%Y-%m-'),'01');  
  
# At present month Last day ：    
SELECT  LAST_DAY(now());  
  
# Previous one month The first day of ：    
SELECT concat(date_format(LAST_DAY(now() - interval 1 month),'%Y-%m-'),'01');  
  
# Previous one month Last day ：    
SELECT LAST_DAY(now() - interval 1 month);  
  
# The first two month The first day of ：    
SELECT concat(date_format(LAST_DAY(now() - interval 2 month),'%Y-%m-'),'01');  
  
# The first two month Last day ：    
SELECT  LAST_DAY(now() - interval 2 month);  
  
# At present quarter The first day of ：    
select concat(date_format(LAST_DAY(MAKEDATE(EXTRACT(YEAR FROM  CURDATE()),1) + interval QUARTER(CURDATE())*3-3 month),'%Y-%m-'),'01');   
  
# At present quarter Last day ：    
select LAST_DAY(MAKEDATE(EXTRACT(YEAR  FROM CURDATE()),1) + interval QUARTER(CURDATE())*3-1 month);  
  
# Previous one quarter The first day of ：    
select concat(date_format(LAST_DAY(MAKEDATE(EXTRACT(YEAR FROM CURDATE()),1) + interval QUARTER(CURDATE())*3-6 month),'%Y-%m-'),'01');  
  
# Previous one quarter Last day ：    
select  LAST_DAY(MAKEDATE(EXTRACT(YEAR FROM CURDATE()),1) + interval QUARTER(CURDATE())*3-4 month);  
  
# The first two quarter The first day of ：    
select concat(date_format(LAST_DAY(MAKEDATE(EXTRACT(YEAR FROM CURDATE()),1) + interval QUARTER(CURDATE())*3-9 month),'%Y-%m-'),'01');  
  
# The first two quarter Last day ：    
select LAST_DAY(MAKEDATE(EXTRACT(YEAR FROM CURDATE()),1) + interval QUARTER(CURDATE())*3-7 month);