Convert Character Date to Numeric (I know this has been asked before)

[UdayGuntupalli]

All, 
   I know there are many posts on the community and I tried following the suggestions in these posts without much success. Here is a very relevant post (https://communities.sas.com/t5/SAS-Programming/URGENT-extract-Year-and-Month-from-a-date-variable/td...) . 

   Let me show what I have tried to do and my code: 

Data Have; 
	Set Work.temp (Keep = UtcReadTime ); 
	Left = scan(UtcReadTime,1,'T');
  	Right = scan(UtcReadTime,2,'T');
  	format Left yymmdd8.; 
  	format Right yymmdd8.; 
  	Date = input(Left,yymmdd8.);
  	Year = Year(Date); 
  	Month = Month(Date); 
  	Day = Day(Date); 
  	Hour = Hour(Right);
Run; 

[UdayGuntupalli]

This seems to work, but I am curious as to why my previous approach does not work : 

Data Have; 
	Set Work.sitepvforecast (Keep = UtcReadTime ); 
	Left = scan(UtcReadTime,1,'T');
  	Right = scan(UtcReadTime,2,'T');
  	Year = substr(Left,1,4);
  	Year_n = input(Year, best12.);
  	Month = substr(Left,6,2); 
  	Month_n = input(Month,best12.); 
  	Day = substr(Left,9,2);
  	Day_n = input(Day,best12.);
  	Hour = substr(Right,1,2);
  	Hour_n = input(Hour,best12.); 
Run; 

[PGStats]

SAS functions YEAR, MONTH, DAY, etc. work on SAS dates which are numbers. You were applying them to character strings.

204  data _null_;
205  t = today();
206  y = year(t);
207  m = month(t);
208  d = day(t);
209  str = put(t, yymmdd10.);
210  put (_all_) (=);
211  run;

t=21606 y=2019 m=2 d=26 str=2019-02-26

[UdayGuntupalli]

@PGStats , 
       Thank you for your response. If you look at the link that I posted, the solution achieved in that discussion also goes through a similar set of steps. 

If your source variable is CHARACTER then you need to make a NEW variable if want to store it as an actual date value.

data want ;
  set have ;
  first_chemo_date_num=input(first_chemo_date,yymmdd8.);
  format first_chemo_date_num yymmddn8.;
  yr=year(first_chemo_date_num);
  mth=month(first_chemo_date_num);
run;

I understand that I am starting of with a character, however I thought the input function was supposed to cast it into a numeric date as explained in this example and that is what I tried. Just to be clear, besides the example code I posted, I also tried creating a new variable exactly as shown . 

[PGStats · Accepted solution]

The only problem with your code was the width of the informat. By asking yymmdd8. you were missing the last two characters of the date part of the string. Look:

218  data _null_;
219  str = "2019-02-27T04:00:00";
220  date = input(str, yymmdd10.);
221  format date yymmddn8.;
222  put (_all_) (=);
223  run;

str=2019-02-27T04:00:00 date=20190227