SQL query to delete records from a query - sql

Question

I am trying to write 2 queries to delete records where dates are greater than a certain date:
The first one:
delete from RPT_HistSnapEng_temp
where ForecastDate> DATEADD(WEEK,7,CAST(GETDATE() AS DATE))
This query deletes records when forecastdate is greater than 7 weeks from today
The second one is:
delete from RPT_HistSnapEng_temp
where ForecastDate< DATEADD(WEEK,-6,CAST(GETDATE() AS DATE))
This query deletes records when forecastdate is less than 6 weeks from today.
So basically, this should filter out records from Dec 2015 - Nov 2016 and only show records from previous 6 weeks and next 7 weeks from today.
Even though the query runs, its not deleting records. I cannot hardcode dates because I will be using this query on a rolling basis inside a SSIS package.

Answer 1

Your current where clauses are trying to grab records that are both less than a date in the past AND greater than a date in the future. I think you (and the other answer) should be using or.
But, since this looks like a temp table that you are loading to then report with, I would adjust your insert to simply grab the records you are looking for, rather than loading more than you need and then deleting.
select *
from RPT_HistSnapEng -- base table name?
where cast(ForecastDate as date) between dateadd(week, -6, cast(current_timestamp as date)) and dateadd(week, 7, cast(current_timestamp as date))
Just add your insert to that if it gets the records you need.
However, to directly answer your question about deletes, you can change this query to simply use NOT between:
delete
from RPT_HistSnapEng_temp
where cast(ForecastDate as date) not between dateadd(week, -6, cast(current_timestamp as date)) and dateadd(week, 7, cast(current_timestamp as date))
As you can see, I like the use of between (which is inclusive of the date arguments) for this type of range check rather than getting caught up in using >= and < or confusing the and and or which you've seemingly done. I also like the ANSI standard current_timestamp over the t-sql specific getdate() but they are equivalent.

Answer 2

Try "ww" or "wk" instead of "week" in the dateadd function. Try a SELECT statement to get the records you want to delete:
SELECT ID, ForecastDate
FROM RPT_HistSnapEng_temp
WHERE CAST(ForecastDate AS DATE) > DATEADD(ww,7,CAST(GETDATE() AS DATE))
OR CAST(ForecastDate AS DATE) < DATEADD(WEEK,-6,CAST(GETDATE() AS DATE))
ORDER BY ForecastDate
To Delete just remove the SELECT and the ORDER BY:
DELETE
FROM RPT_HistSnapEng_temp
WHERE CAST(ForecastDate AS DATE) > DATEADD(ww,7,CAST(GETDATE() AS DATE))
OR CAST(ForecastDate AS DATE) < DATEADD(WEEK,-6,CAST(GETDATE() AS DATE))