I just need to select the first day of the month of a given DateTime variable.
I know it's quite easy to do using this kind of code:
select CAST(CAST(YEAR(@mydate) AS VARCHAR(4)) + '/' + CAST(MONTH(@mydate) AS VARCHAR(2)) + '/01' AS DATETIME) But unfortunately, this is not very elegant, and not very fast either.
Is there a better way to do this? I'm using SQL Server 2008.
33 Answers
SELECT DATEADD(month, DATEDIFF(month, 0, @mydate), 0) AS StartOfMonth In addition to all the above answer, a way based on a function introduced in sql 2012
SELECT DATEFROMPARTS(YEAR(@mydate),MONTH(@mydate),1) Starting with SQL Server 2012:
SELECT DATEADD(DAY,1,EOMONTH(@mydate,-1)) The casting of a string (i.e. "5/1/2009") to datetime is certainly more legible but we found code a while back that would return the first of the month...
DECLARE @Date DATETIME //... SELECT DATEADD(mm, DATEDIFF(mm,0,@Date), 0) Simple Query:
SELECT DATEADD(m, DATEDIFF(m, 0, GETDATE()), 0) -- Instead of GetDate you can put any date. It is probably quite fast. Why not create it as a sql function.
CREATE FUNCTION [dbo].[GetFirstDayOfMonth] ( @InputDate DATETIME ) RETURNS DATETIME BEGIN RETURN CAST(CAST(YEAR(@InputDate) AS VARCHAR(4)) + '/' + CAST(MONTH(@InputDate) AS VARCHAR(2)) + '/01' AS DATETIME) END GO SELECT @myDate - DAY(@myDate) + 1 This might be a new function, but you can also use old functions :
select DATEFROMPARTS(year(@mydate),month(@mydate),'01') If the date in the variable was for example '2017-10-29' it would return a date of '2017-10-01'
First and last day of the current month:
select dateadd(mm, -1,dateadd(dd, +1, eomonth(getdate()))) as FirstDay, eomonth(getdate()) as LastDay This works too:
SELECT DATEADD(DAY,(DATEPART(DAY,@mydate)-1)*(-1),@mydate) AS FirstOfMonth Please use this
For Server 2012
DATEFROMPARTS(year('2015-06-30'),month('2015-06-30'),1)Before Server 2012
select cast(cast(year('2015-06-30') as varchar(4))+'-'+ cast(month('2015-06-30') as varchar(2))+'-01' as smalldatetime)
I used GETDATE() as a date to work with, you can replace it with the date which you need.
Here's how this works: First we format the date in YYYYMMDD... format truncating to keep just the 6 leftmost characters in order to keep just the YYYYMM portion, and then append '01' as the month - and voila! you have the first day of the current month.
SELECT CAST(CONVERT(VARCHAR(6),GETDATE(),112) +'01' AS DATETIME) AS StartOfMonth BTW, performance is great on this!
DECLARE @startofmonth date SET @startofmonth = DATEADD(dd,1,EOMONTH(Getdate(),-2)) The -2 will get you the first day of last month. ie, getdate() is 10/15/18. Your results would be 9/1/18. Change to -1 and your results would be 10/1/18. 0 would be the start of next month, 11/1/2018.. etc etc.
or
DECLARE @startofmonth date SET @startofmonth = DATEADD(dd,1,EOMONTH(@mydate,-1)) ----Last Day of Previous Month SELECT DATEADD(s,-1,DATEADD(mm, DATEDIFF(m,0,GETDATE()),0)) LastDay_PreviousMonth ----Last Day of Current Month SELECT DATEADD(s,-1,DATEADD(mm, DATEDIFF(m,0,GETDATE())+1,0)) LastDay_CurrentMonth ----Last Day of Next Month SELECT DATEADD(s,-1,DATEADD(mm, DATEDIFF(m,0,GETDATE())+2,0)) LastDay_NextMonth This query should work very well on MySQL:
SELECT concat(left(curdate(),7),'-01') If you would like to go for SQL Server 2012+ you can try solution I used:
SELECT DATEADD(DAY, 1, EOMONTH(DATEADD(MONTH, -1, GETDATE()))) Future googlers, on MySQL, try this:
select date_sub(ref_date, interval day(ref_date)-1 day) as day1; If you are looking at this today, and using SQL server 2012 or newer you have the EOMONTH function which makes things easier:
SELECT DATEADD(day, 1, EOMONTH(DATEADD(month, -1, GETDATE()))) as firstdateofmonth You can change GETDATE() with whatever date variable you want.
Here we can use below query to the first date of the month and last date of the month.
SELECT DATEADD(DAY,1,EOMONTH(Getdate(),-1)) as 'FD',Cast(Getdate()-1 as Date) as 'LD' If using SQL Server 2012 or above;
SELECT DATEADD(MONTH, -1, DATEADD(DAY, 1, EOMONTH(GETDATE()))) Try executing the following query:
SELECT DATE_ADD(DATE_ADD(LAST_DAY(CURRENT_DATE-INTERVAL 1 DAY),INTERVAL 1 DAY),INTERVAL -1 MONTH)
select CONVERT(date,DATEADD(dd,-(DATEPART(dd,getdate())-1),getdate()),120)
This function will provide you date part of start date of the month
SELECT DATEADD (DAY, -1 * (DAY(GETDATE()) - 1), GETDATE()) .....................................................................
If you dont want the time, then convert it to DATE or if want to make to time to 0:00:00, Convert to DATE and then back to DATETIME.
SELECT CONVERT (DATETIME, CONVERT (DATE, DATEADD (DAY, -1 * (DAY(GETDATE()) - 1), GETDATE()))) Change GETDATE() to the date you want
I personal recommended that the sql below because when i try use date function in the condition clause, its slow down my query speed very much.
anyway feel free to try this.
select CONCAT(DATEPART(YYYY,@mydate),'-',DATEPART(MM,@mydate),'-01') Not to compete with any of the great minds here, but a simple suggestion slightly different that the accepted answer above.
select dateadd(day, -(datepart(day,@date)+1,@date) I like to use FORMAT, you can even specify a time
SELECT FORMAT(@myDate,'yyyy-MM-01 06:00') first_of_a_month In Sql Server 2012,
select getdate()-DATEPART(day, getdate())+1 select DATEADD(Month,1,getdate())-DATEPART(day, getdate()) For anyone still looking for an answer, this works like a charm and does away with any dateadds. The timestamp is optional, in case it needs specifying, but works without as well.
SELECT left(convert(varchar, getdate(),23),7)+'-01 00:00:00' Get First Date and Last Date in the Date we pass as parameter in SQL
@date DATETIME SELECT @date = GETDATE() SELECT CONVERT(VARCHAR(25),DATEADD(dd,-(DAY(@date)-1),@date),105) AS value, 'First Day of Current Month' AS name UNION SELECT CONVERT(VARCHAR(25),DATEADD(dd,-(DAY(DATEADD(mm,1,@date))), DATEADD(mm,1,@date)),105), 'Last Day of Current Month' GO **OutPut** 12/01/2019 First Day of Current Month 12/31/2019 Last Day of Current Month What about something different! Use Format.
DECLARE @Date Date =GetDate(); SELECT CONVERT(Date,Format(@Date,'yyyyMM01')); We can remove the convert if we are casting to Date Column or variable
DECLARE @Date Date =GetDate(); SELECT @Date =Format(@Date,'yyyyMM01'); SELECT [Date]=@Date Have Fun :)
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