Worked out a function to convert integer yyyymmdd to an Excel date: Function IBDates2ExcelDates(lIBDate As Long) As Long
Dim lYear As Long Dim lMonth As Long Dim lDay As Long Dim a As Long Dim y As Long Dim m As Long Dim lJulianDay As Long lYear = lIBDate \ 10000 lMonth = (lIBDate - lYear * 10000) \ 100 lDay = lIBDate - (lYear * 10000 + lMonth * 100) a = (14 - lMonth) / 12 y = lYear + 4800 - a m = lMonth + 12 * a - 3 lJulianDay = lDay + (153 * m + 2) / 5 + y * 365 + y / 4 - 32083 IBDates2ExcelDates = lJulianDay - 2415033 End Function Seems to work well. I know there is a bug in the Excel date where somewhere shortly after 30 December 1899 it is one day out, but that is OK. And I suppose this is something I can do in SQLite? If so should I just put this in the query statement or can I somehow make a UDF? RBS -----Original Message----- From: John Stanton [mailto:[EMAIL PROTECTED] Sent: 03 December 2006 18:23 To: sqlite-users@sqlite.org Subject: Re: [sqlite] Dealing with dates in the format yyyymmdd What do you mean by "integer format yyymmdd"? Is it an integer based on an epoch or is it a number like 20061203 stored in a 32 bit word? We use Sqlite format dates and times and thereby get good SQL capability and have a small library of date function which interface into Unix and Windows date and time retrieval APIs. A couple of simple Sqlite custom functions to do some date manipulation made the SQL simpler. Custom date functions are very easy to implement using Sqlite because you can use the Sqlite date routines and style as a basis. The Sqlite epoch based date format is elegant because it permits you to present date and time not only according to any time zone but to comply with more than just the Gregorian calendar - with Middle Eastern and Oriental ones should the need arise. RB Smissaert wrote: > Trouble is I need to import dates from Interbase that have the integer > format yyyymmdd. How would I convert that (at import) to the SQLite date > format? I do the import via an ADO recordset and then move the data via > SQLite inserts. > > RBS > > -----Original Message----- > From: John Stanton [mailto:[EMAIL PROTECTED] > Sent: 03 December 2006 17:01 > To: sqlite-users@sqlite.org > Subject: Re: [sqlite] Dealing with dates in the format yyyymmdd > > Why not use the internal Sqlite date format. Then date processing is > straight forward and you can use the conversion routines to present it > in the various national and ISO formats. > > Sqlite uses a very correct date storage format based on an epoch way > back in antiquity so that you can present it in any national format. > > Using the internal format date comparison is just a numeric compare, > which is efficient. > > If you need any special date presentation you can add a custome function > to Sqlite to achieve it from your SQL statement. > > RB Smissaert wrote: > >>Just thought of one reason why it I need something else in SQLite than >>yyyymmdd in the date field and that is because I need date comparisons >>between different tables. So, I need to do: is fieldA + x days > fieldB? >>etc. >>This will be difficult with the yyyymmdd format. I could of course update >>all the date fields in a VBA loop, but that might be a bit slow. So, if >>anybody has an idea how to convert integer yyyymmdd to the Excel date > > format > >>in SQLite I would be interested. >> >>RBS >> >>-----Original Message----- >>From: RB Smissaert [mailto:[EMAIL PROTECTED] >>Sent: 03 December 2006 15:37 >>To: sqlite-users@sqlite.org >>Subject: RE: [sqlite] Dealing with dates in the format yyyymmdd >> >>I think it is easier to do this in VBA and as the main work is done in a > > VBA > >>array it is quite fast as well. Not as elegant maybe as doing it in > > SQLite, > >>but it will do. >> >>RBS >> >>-----Original Message----- >>From: Fred Williams [mailto:[EMAIL PROTECTED] >>Sent: 03 December 2006 14:41 >>To: sqlite-users@sqlite.org >>Subject: RE: [sqlite] Dealing with dates in the format yyyymmdd >> >>Is there a reason you can use Excel's "Format Cells" to accomplish what >>you wish? Enter a "Custom" format of "yyyy\mm\dd" in a cell and enter >>"=today()" as a value in that cell. Have not fooled with Excel much >>lately, but I think you can even format a spreadsheet programmatically. >> >>Fred >> >> >> >>>-----Original Message----- >>>From: RB Smissaert [mailto:[EMAIL PROTECTED] >>>Sent: Sunday, December 03, 2006 8:21 AM >>>To: sqlite-users@sqlite.org >>>Subject: [sqlite] Dealing with dates in the format yyyymmdd >>> >>> >>>When moving data from Interbase to SQLite I have to convert >>>integer dates in >>>the format yyyymmdd to Excel dates. These are integer numbers >>>counting the >>>days past 31 December 1899. With substr I can make it >>>dd/mm/yyyy (I am in >>>the UK and that is the normal way to format dates) but the >>>problem is it >>>will be displayed in Excel like mm/dd/yyyy if that would be a >>>possible date. >>>This is due to the US date format of Excel. >>>So, would it be possible in SQLite to make a date format like this: >>>dd/mmm/yyyy so that would be 03/dec/2006 >>>This would prevent Excel from putting the month first. >>>or alternatively make it the Excel integer date format so the >>>above date >>>would be: 39054 >>> >>>I could handle the date formatting in VBA, but I would like >>>to do as much as >>>possible in SQLite as it will be faster and it would keep the >>>code neater. >>>Thanks for any advice. >>> >>>RBS >>> >>> >>> >>> >>>-------------------------------------------------------------- >>>--------------- >>>To unsubscribe, send email to [EMAIL PROTECTED] >>>-------------------------------------------------------------- >>>--------------- >>> >> >> >> >> > ---------------------------------------------------------------------------- > >>- >>To unsubscribe, send email to [EMAIL PROTECTED] >> > > ---------------------------------------------------------------------------- > >>- >> >> >> >> >> > > ---------------------------------------------------------------------------- > >>- >>To unsubscribe, send email to [EMAIL PROTECTED] >> > > ---------------------------------------------------------------------------- > >>- >> >> >> >> >> > > ---------------------------------------------------------------------------- > - > >>To unsubscribe, send email to [EMAIL PROTECTED] >> > > ---------------------------------------------------------------------------- > - > > > > ---------------------------------------------------------------------------- > - > To unsubscribe, send email to [EMAIL PROTECTED] > ---------------------------------------------------------------------------- > - > > > > > ---------------------------------------------------------------------------- - > To unsubscribe, send email to [EMAIL PROTECTED] > ---------------------------------------------------------------------------- - > ---------------------------------------------------------------------------- - To unsubscribe, send email to [EMAIL PROTECTED] ---------------------------------------------------------------------------- - ----------------------------------------------------------------------------- To unsubscribe, send email to [EMAIL PROTECTED] -----------------------------------------------------------------------------
