SQL Server getting value within a week time period
I need some guidance in getting value from the database within a week time period. I've figured out how to use DATEPART
where I can do DATEPART(wk, date_value) = DATEPART(datepart, GETDATE())
but what I can't figure out is how to do a specific day of the week. Like I only want to retrieve information from this Tuesday to next Tuesday. Can anyone offer anyone offer any guidance?
Thanks!
In SQL Server, you can do something like this:
Set DateFirst 1;
Select DateAdd(d, -DatePart(dw, CURRENT_TIMESTAMP) + 3
, CURRENT_TIMESTAMP) As ThisWeekTuesday
, DateAdd(d, 7, DateAdd(d, -DatePart(dw, CURRENT_TIMESTAMP) + 3
, CURRENT_TIMESTAMP)) As TuesdayAfterThat
In MIcrosoft Access, you would do something like:
Select DateAdd("d", -DatePart("w", Now()) + 3, Now()) As ThisWeekTuesday
, DateAdd("d", 7, DateAdd("d", -DatePart("w", Now()) + 3
, Now())) As TuesdayAfterThat
I recommend creating a Dates table - store one record per day, with fields for SQLDate, DateAsText, Year, Month, MonthAsText, DayOfWeek, DayOfWeekAsText, etc. Then you can query like this:
SELECT
MIN(SQLDate)
FROM
Dates
WHERE
SQLDate > SYSDATETIME()
AND DayOfWeekText = 'Tuesday'
If you'd rather not go through that right now, you can also use DATEPART() and DATEADD(). For the next coming Tuesday, I believe this would be:
DECLARE @TodaysDayOfWeek = DATEPART(DW, SYSDATETIME())
SELECT
CASE WHEN @TodaysDayOfWeek < 3 DATEADD( 3 - @TodaysDayOfWeek, SYSDATETIME())
ELSE DATEADD(10 - @TodaysDayOfWeek, SYSDATETIME() END
I don't have MS SQL handy to confirm this, but it should work if DW starts at 1 for Sunday and ends with 7 for Saturday (this can vary depending on your config). Note that, if called on a Tuesday it will give next Tuesday, not today; to reverse this behavior, change "< 3" to "<= 3".
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