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问题:
I want to get the records of last month based on my db table [member] field "date_created".
What's the sql to do this?
For clarification,
last month - 1/8/2009 to 31/8/2009
If today is 3/1/2010, I'll need to get the records of 1/12/2009 to 31/12/2009.
回答1:
SELECT *
FROM Member
WHERE DATEPART(m, date_created) = DATEPART(m, DATEADD(m, -1, getdate()))
AND DATEPART(yyyy, date_created) = DATEPART(yyyy, DATEADD(m, -1, getdate()))
You need to check the month and year.
回答2:
All the existing (working) answers have one of two problems:
- They will ignore indices on the column being searched
- The will (potentially) select data that is not intended, silently corrupting your results.
1. Ignored Indices:
For the most part, when a column being searched has a function called on it (including implicitly, like for CAST
), the optimizer must ignore indices on the column and search through every record. Here's a quick example:
We're dealing with timestamps, and most RDBMSs tend to store this information as an increasing value of some sort, usually a long
or BIGINTEGER
count of milli-/nanoseconds. The current time thus looks/is stored like this:
1402401635000000 -- 2014-06-10 12:00:35.000000 GMT
You don't see the 'Year' value ('2014'
) in there, do you? In fact, there's a fair bit of complicated math to translate back and forth. So if you call any of the extraction/date part functions on the searched column, the server has to perform all that math just to figure out if you can include it in the results. On small tables this isn't an issue, but as the percentage of rows selected decreases this becomes a larger and larger drain. Then in this case, you're doing it a second time for asking about MONTH
... well, you get the picture.
2. Unintended data:
Depending on the particular version of SQL Server, and column datatypes, using BETWEEN
(or similar inclusive upper-bound ranges: <=
) can result in the wrong data being selected. Essentially, you potentially end up including data from midnight of the "next" day, or excluding some portion of the "current" day's records.
What you should be doing:
So we need a way that's safe for our data, and will use indices (if viable). The correct way is then of the form:
WHERE date_created >= @startOfPreviousMonth AND date_created < @startOfCurrentMonth
Given that there's only one month, @startOfPreviousMonth
can be easily substituted for/derived by:
DATEADD(month, -1, @startOCurrentfMonth)
If you need to derive the start-of-current-month in the server, you can do it via the following:
DATEADD(month, DATEDIFF(month, 0, CURRENT_TIMESTAMP), 0)
A quick word of explanation here. The initial DATEDIFF(...)
will get the difference between the start of the current era (0001-01-01
- AD, CE, whatever), essentially returning a large integer. This is the count of months to the start of the current month. We then add this number to the start of the era, which is at the start of the given month.
So your full script could/should look similar to the following:
DECLARE @startOfCurrentMonth DATETIME
SET @startOfCurrentMonth = DATEADD(month, DATEDIFF(month, 0, CURRENT_TIMESTAMP), 0)
SELECT *
FROM Member
WHERE date_created >= DATEADD(month, -1, @startOfCurrentMonth) -- this was originally misspelled
AND date_created < @startOfCurrentMonth
All date operations are thus only performed once, on one value; the optimizer is free to use indices, and no incorrect data will be included.
回答3:
Add the options which have been provided so far won't use your indexes at all.
Something like this will do the trick, and make use of an index on the table (if one exists).
DECLARE @StartDate DATETIME, @EndDate DATETIME
SET @StartDate = dateadd(mm, -1, getdate())
SET @StartDate = dateadd(dd, datepart(dd, getdate())*-1, @StartDate)
SET @EndDate = dateadd(mm, 1, @StartDate)
SELECT *
FROM Member
WHERE date_created BETWEEN @StartDate AND @EndDate
回答4:
DECLARE @StartDate DATETIME, @EndDate DATETIME
SET @StartDate = DATEADD(mm, DATEDIFF(mm,0,getdate())-1, 0)
SET @EndDate = DATEADD(mm, 1, @StartDate)
SELECT *
FROM Member
WHERE date_created BETWEEN @StartDate AND @EndDate
An upgrade to mrdenny's solution, this way you get exactly last month from YYYY-MM-01
回答5:
Last month consider as till last day of the month.
31/01/2016 here last day of the month would be 31 Jan. which is not similar to last 30 days.
SELECT CONVERT(DATE, DATEADD(DAY,-DAY(GETDATE()),GETDATE()))
回答6:
One way to do it is using the DATEPART function:
select field1, field2, fieldN from TABLE where DATEPART(month, date_created) = 4
and DATEPART(year, date_created) = 2009
will return all dates in april. For last month (ie, previous to current month) you can use GETDATE and DATEADD as well:
select field1, field2, fieldN from TABLE where DATEPART(month, date_created)
= (DATEPART(month, GETDATE()) - 1) and
DATEPART(year, date_created) = DATEPART(year, DATEADD(m, -1, GETDATE()))
回答7:
declare @PrevMonth as nvarchar(256)
SELECT @PrevMonth = DateName( month,DATEADD(mm, DATEDIFF(mm, 0, getdate()) - 1, 0)) +
'-' + substring(DateName( Year, getDate() ) ,3,4)
回答8:
SQL query to get record of the present month only
SELECT * FROM CUSTOMER
WHERE MONTH(DATE) = MONTH(CURRENT_TIMESTAMP) AND YEAR(DATE) = YEAR(CURRENT_TIMESTAMP);
回答9:
select * from [member] where DatePart("m", date_created) = DatePart("m", DateAdd("m", -1, getdate())) AND DatePart("yyyy", date_created) = DatePart("yyyy", DateAdd("m", -1, getdate()))
回答10:
DECLARE @StartDate DATETIME, @EndDate DATETIME
SET @StartDate = DATEADD(mm, DATEDIFF(mm, 0, getdate()) - 1, 0)
SET @EndDate = dateadd(dd, -1, DATEADD(mm, 1, @StartDate))
SELECT * FROM Member WHERE date_created BETWEEN @StartDate AND @EndDate
and another upgrade to mrdenny's solution.
It gives the exact last day of the previous month as well.
回答11:
WHERE
date_created >= DATEADD(MONTH, DATEDIFF(MONTH, 31, CURRENT_TIMESTAMP), 0)
AND date_created < DATEADD(MONTH, DATEDIFF(MONTH, 0, CURRENT_TIMESTAMP), 0)
回答12:
I'm from Oracle env and I would do it like this in Oracle:
select * from table
where trunc(somedatefield, 'MONTH') =
trunc(sysdate -INTERVAL '0-1' YEAR TO MONTH, 'MONTH')
Idea: I'm running a scheduled report of previous month (from day 1 to the last day of the month, not windowed). This could be index unfriendly, but Oracle has fast date handling anyways.
Is there a similar simple and short way in MS SQL? The answer comparing year and month separately seems silly to Oracle folks.
回答13:
You can get the last month records with this query
SELECT * FROM dbo.member d
WHERE CONVERT(DATE, date_created,101)>=CONVERT(DATE,DATEADD(m, datediff(m, 0, current_timestamp)-1, 0))
and CONVERT(DATE, date_created,101) < CONVERT(DATE, DATEADD(m, datediff(m, 0, current_timestamp)-1, 0),101)
回答14:
In Sql server for last one month:
select * from tablename
where order_date > DateAdd(WEEK, -1, GETDATE()+1) and order_date<=GETDATE()
回答15:
DECLARE @curDate INT = datepart( Month,GETDATE())
IF (@curDate = 1)
BEGIN
select * from Featured_Deal
where datepart( Month,Created_Date)=12 AND datepart(Year,Created_Date) = (datepart(Year,GETDATE())-1)
END
ELSE
BEGIN
select * from Featured_Deal
where datepart( Month,Created_Date)=(datepart( Month,GETDATE())-1) AND datepart(Year,Created_Date) = datepart(Year,GETDATE())
END
回答16:
DECLARE @StartDate DATETIME, @EndDate DATETIME
SET @StartDate = dateadd(mm, -1, getdate())
SET @StartDate = dateadd(dd, datepart(dd, getdate())*-1, @StartDate)
SET @EndDate = dateadd(mm, 1, @StartDate)
set @StartDate = DATEADD(dd, 1 , @StartDate)
回答17:
The way I fixed similar issue was by adding Month to my SELECT portion
Month DATEADD(day,Created_Date,'1971/12/31') As Month
and than I added WHERE statement
Month DATEADD(day,Created_Date,'1971/12/31') = month(getdate())-1
回答18:
If you are looking for last month so try this,
SELECT
FROM #emp
WHERE DATEDIFF(MONTH,CREATEDDATE,GETDATE()) = 1
If you are looking for last month so try this,
SELECT
FROM #emp
WHERE DATEDIFF(day,CREATEDDATE,GETDATE()) between 1 and 30
回答19:
A simple query which works for me is:
select * from table where DATEADD(month, 1,DATEFIELD) >= getdate()
回答20:
If you are looking for previous month data:
date(date_created)>=date_sub(date_format(curdate(),"%Y-%m-01"),interval 1 month) and
date(date_created)<=date_sub(date_format(curdate(),'%Y-%m-01'),interval 1 day)
This will also work when the year changes. It will also work on MySQL.