First & Last days of the month with time stamp macros - sql

Question

I have a SAS program I want to automate to run. I have to pull the first date & the last date of the month with the time stamps.
This is what it looks like hard coded - that does work! But I don't want to change it every month.
%let st_dt= '2020-10-01-00.00.00';
%let ed_dt= '2020-10-31-23.59.59';
PROC SQL;
SELECT t1.ENTRYTIME
FROM MYTABLE t1
WHERE t1.ENTRYTIME BETWEEN &st_dt. AND &ed_dt.
I have tried so many different things but cannot seem to get it to work. And BONUS, I'm pulling from transactional tables that have over 17 BILLION - yes BILLION WITH A B records. I've tried using datepart on the ENTRYTIME & casting as a date - but with that many records it just runs forever and eventually gets killed - or just flat out fails! :(
This is what I've tried so far - neither PROC SQL work.
%let start=%sysfunc(intnx(month, %sysfunc(today()),-1), date9.);
%let end=%sysfunc(intnx(month, %sysfunc(today()),-1,e), date9.);
PROC SQL;
SELECT t1.ENTRYTIME
FROM MYTABLE t1
WHERE cast(t1.ENTRYTIME as date) BETWEEN &start. AND &end.
PROC SQL;
SELECT t1.ENTRYTIME
FROM MYTABLE t1
WHERE cast(t1.ENTRYTIME as date) BETWEEN &start. AND &end.
So if you can get me a macro or a let statement or anything that is formatted like this to automatically update without human intervention: '2020-10-01-00.00.00' & '2020-10-31-23.59.59' - BRING IT ON! Thank you for your help!!

Answer 1

Just tack on the time suffix as constant text.
%let st_dt= "%sysfunc(intnx(month,%sysfunc(today()),-1,b),yymmddd10.)-00.00.00";
%let ed_dt= "%sysfunc(intnx(month,%sysfunc(today()),-1,e),yymmddd10.)-23.59.59";

Answer 2

You probably want to pass through to ensure best performance. The core syntax in the pass through is
entrytime >= 'yyyymmdd' and entrytime < 'yyyymmdd'
^^^^^^^^ ^^^^^^^^
1st of month 2nd of month
or
entrytime >= 'yyyymmdd' and entrytime < 'yyyymmdd'
^^^^^^^^ ^^^^^^^^
last of month 1st of next month
Example:
%let today = %sysfunc(date());
%let month_first_dt = %sysfunc(intnx(MONTH,&today,0));
%let month_last_dt = %sysfunc(intnx(MONTH,&today,0,E));
%let month_first = %sysfunc(intnx(DAY,&month_first_dt,0),yymmddn8.);
%let month_first_next = %sysfunc(intnx(DAY,&month_first_dt,1),yymmddn8.);
%let month_last = %sysfunc(intnx(DAY,&month_last_dt,0),yymmddn8.);
%let month_last_next = %sysfunc(intnx(DAY,&month_last_dt,1),yymmddn8.);
%let ss_MF_literal = %sysfunc(quote(&month_first,%str(%')));
%let ss_MFN_literal = %sysfunc(quote(&month_first_next,%str(%')));
%let ss_ML_literal = %sysfunc(quote(&month_last,%str(%')));
%let ss_MLN_literal = %sysfunc(quote(&month_last_next,%str(%')));
libname remote sqlsrv 'connection string';
proc sql;
create table sas_table as select * from connection to remote
(
select entrytime from remote-table-name
where
entrytime >= &ss_MF_literal and entrytime < &ss_MFN_literal
or
entrytime >= &ss_ML_literal and entrytime < &ss_MLN_literal
)
;