convert Excel Date Serial Number to Regular Date

Question

I got a column called DateOfBirth in my csv file with Excel Date Serial Number Date

Example:

  36464
  37104
  35412

When i formatted cells in excel these are converted as

  36464 => 1/11/1999
  37104 => 1/08/2001
  35412 => 13/12/1996

I need to do this transformation in SSIS or in SQL. How can this be achieved?

Solution 1

In SQL:

select dateadd(d,36464,'1899-12-30')
-- or thanks to rcdmk
select CAST(36464 - 2 as SmallDateTime)

In SSIS, see here

http://msdn.microsoft.com/en-us/library/ms141719.aspx

Solution 2

The marked answer is not working fine, please change the date to "1899-12-30" instead of "1899-12-31".

select dateadd(d,36464,'1899-12-30')

Solution 3

You can cast it to a SQL SMALLDATETIME:

CAST(36464 - 2 as SMALLDATETIME)

MS SQL Server counts its dates from 01/01/1900 and Excel from 12/30/1899 = 2 days less.

Solution 4

this actually worked for me

dateadd(mi,CONVERT(numeric(17,5),41869.166666666664)*1440,'1899-12-30') 

(minus 1 more day in the date)

referring to the negative commented post

Solution 5

tldr:

select cast(@Input - 2e as datetime)

Explanation:

Excel stores datetimes as a floating point number that represents elapsed time since the beginning of the 20th century, and SQL Server can readily cast between floats and datetimes in the same manner. The difference between Excel and SQL server's conversion of this number to datetimes is 2 days (as of 1900-03-01, that is). Using a literal of 2e for this difference informs SQL Server to implicitly convert other datatypes to floats for very input-friendly and simple queries:

select
    cast('43861.875433912' - 2e as datetime) as ExcelToSql, -- even varchar works!
    cast(cast('2020-01-31 21:00:37.490' as datetime) + 2e as float) as SqlToExcel

-- Results:
-- ExcelToSql                          SqlToExcel
-- 2020-01-31 21:00:37.490        43861.875433912

View more solutions

Comments

[bp_]

FYI: the 2 days less issue is much more fun than your incorrect assessment. Mr. Gates himself approved the date oddity. See these two resources: MS Support , The real Story And, yes, the creator of Stack Overflow did have a huge role to play in the whole thing.

[Nicolaesse]

what does "mi" mean in the first part of the formula?

[drinky]

mi = minute as the datepart in the dateadd formula. msdn.microsoft.com/en-us/library/ms186819.aspx

[Tim Lehner]

I use something similar, but I find that the input parameter as a float is much more general.

[justbeez]

For people landing here and looking for a more brief solution for BigQuery, try SELECT DATETIME_ADD("1899-12-30",INTERVAL CAST(43909.91492 * 86400 AS INT64) SECOND) (also, the answer above seems to be off by one second; both Excel and my code put that serial at 2018-09-03 16:23:29)

[kiltannen]

I think this answer is a bit cleaner & the comment above giving a link to Joel's blog article is just insanely awesome!