I'm facing date format problems in Delphi 10.4 CE.
If the date fields are created in SQL server with DateTime format, and a date field is incremented in the application with a specific number of days using the System.DateUtils.IncDay() function while the source date is 01/10/2022, I get the result as 01/09/1900 in the DBEdit component and in DBGrid when incremented by 10 days.
However, if I recreate date fields with formatting as Date fields (and not DateTime), the increment function shows errors like:
'' is not a valid date and time
Moreover, if I skip the increment function and add a record to the SQL table, the dates are shown in the format dd/mm/yyyy, but after adding records once, if I close the session and restart the application, all dates show up in the format yyyy-mm-dd.
Following is the source code to calculate the incremented date:
tblLeaveAzr.FieldByName('leaveend').AsDateTime := IncDay(tblLeaveAzr.FieldByName('leavestart').AsDateTime,tblLeaveAzr.FieldByName('leavedays').AsInteger);
I have been working in Delphi 6, 7 and 2009 for more than 20 years, but never faced such a problem.
Related
I'm building an iOS app where I want to retrieve all the values from my database between two dates that the user picks. So for example, I want all the rows from the 1st of March to the 5th of March. Would look something like
SELECT * FROM MAIN WHERE DATE = '01/03/2020' AND ENDS ='05/03/2020'
So from that I would hope to retrieve all data from the 1st,2nd,3rd,4th and 5th of march. Any ideas on how to do this?
Thank you
Try to use comparison operators like:
DATE >= '01/03/2020' AND DATE <= '05/03/2020'
There are two issues:
Date types:
As Datatypes In SQLite Version 3 says:
2.2. Date and Time Datatype
SQLite does not have a storage class set aside for storing dates and/or times. Instead, the built-in Date And Time Functions of SQLite are capable of storing dates and times as TEXT, REAL, or INTEGER values:
TEXT as ISO8601 strings ("YYYY-MM-DD HH:MM:SS.SSS").
REAL as Julian day numbers, the number of days since noon in Greenwich on November 24, 4714 B.C. according to the proleptic Gregorian calendar.
INTEGER as Unix Time, the number of seconds since 1970-01-01 00:00:00 UTC.
Applications can chose to store dates and times in any of these formats and freely convert between formats using the built-in date and time functions.
So storing dates in a dd/MM/yyyy format (using the DateFormatter capitalization convention) is problematic because in the absence of a native date type, it’s going to store them as strings, and therefore all comparisons will be done alphabetically, not chronologically, sorting values like 03/10/2009 (or nonsense strings like 02foobar, for that matter) in between the strings 01/05/2020 and 05/05/2020.
If, however you store them as yyyy-MM-dd, then it just so happens that alphabetical comparisons will yield chronologically correct comparisons, too.
SQL syntax:
Once you have your dates in your database in a format that is comparable, then if you have all of your dates in a single column, you can use the BETWEEN syntax. For example, let’s say you stored all of your dates in yyyy-MM-dd format, then you could do things like:
SELECT * FROM main WHERE date BETWEEN '2020-03-01' AND '2020-03-05';
But needless to say, you can’t use this pattern (or any comparison operators other than equality) as long as your dates are stored in dd/MM/yyyy format.
If you want to show all the data that has values of column "date" between this two dates then:
Select *
from MAIN
where `date` between '01.03.2020' and '05.03.2020';
If you want to show all the data that has values of column "ends" between this two dates then:
Select *
from MAIN
where ends between '01.03.2020' and '05.03.2020';
If you want to show all the data that has values of columns "date" and "ends" between this two dates then:
Select *
from MAIN
where ends between '01.03.2020' and '05.03.2020'
and `date` between '01.03.2020' and '05.03.2020';
Here is a demo
In the process of migrating one of my Win32 VCL application from Delphi 2006 to delphi XE6 I encountered the following issue :
One of my forms has a TMonthCalendar (plugged on a TPanel for the record) to help the user select a week to view in a graph. By week I mean Monday being the first day and Sunday the last (french locale). To achieve such a week selection pattern I set the multiSelect property to true and put the following code inside the CalendarClick event :
MonthCalendar1.MultiSelect := True;
//Temporarily storing the selected day in a variable
TempoDate := MonthCalendar1.Date;
//searching for the monday right before the selected day (by user)
while dayOfWeek(TempoDate) <> 2 do
TempoDate := IncDay( TempoDate , -1 );
//Setting the monday as the start date of the selection
MonthCalendar1.Date := TempoDate;
//Setting the Sunday as the last day of selection
MonthCalendar1.EndDate := IncDay(tempoDate, 6);
That used to work well on Delphi 2006 ( compiled on a win XP computer ).
Now that I have ported the same code to Delphi XE6 ( compiled on a win7 computer ) I have the following problems :
When clicking the right arrow (>) to switch to the next month it fails most of the time. It actually fails when the monday of the week containing the 1st of the next month is still in the previous month. Ex : switching from Sept '14 to Oct '14 fails because the monday before Oct. 1st is in september (Monday Sept. 29th).
So that brings me back to September.
On the other hand, switching from August 14 to September 14 works because Sept. 1st is a monday.
When clicking on the first days of the next month (the few grey one you can click on) the month doesn't switch anymore.
all that used to work before.
I've made some specific isolation tests :
Creating a minimal app under XE6 with the same behaviour -> still fails (of course)
Creating the same minimal app under Delphi 2006 -> it all work as expected.
My intuition is that the TMonthCalendar now takes the .Date property to define which month to show, while on D2006 it used to take .EndDate property.
Doesn't know if this is a VCL evolution or a microsoft MonthCalendar underlying component behaviour change (since i compiled on XP then SEVEN ).
Thanks for your help
Useful documentation :
http://docwiki.embarcadero.com/Libraries/XE7/en/Vcl.ComCtrls.TMonthCalendar
http://msdn.microsoft.com/en-us/library/system.windows.forms.monthcalendar(v=vs.110).aspx
Unfortunately I can't provide you with solution but athleast I have eplanation for current behavior.
The problem you are facing is the TMonthCalender controll itself and which date fields is trated as selected even when using multiselect.
If you take a good look you will notice that even when using multiselect one day always have doted square around it. That date controls which month is focused.
So now you need to figure out how to change that behavior working with multiple selection enabled. I laredy tried setting the Date and EndDate properties so that EndDate value was actually lower since I thought that doing so miygt force MonthCalendar to treat last day of the weak to be selected when detirmining which month is focused but it has no effect. But it has no effect.
As for finding starting and ending week date use these functions:
TempDate := MonthCalendar1.Date;
WeekStart := StartOfTheWeek(TempDate);
WeekEnd := EndOfTheWeek(TempDate);
Both of these functions treat monday as fist day of the week.
I wish I could have helped you more.
I change calendar javascript to Hijri, But another problem comes up. It seems that a class (DueDateValidator.class) try to validate input date, while the number of days in month is different to georgian calendar. for example we have 31 days in second month of year but in georgian (february) it is 28 or 29.
I don't think there is an out-of-the-box option to cancel Jira's date validation. You could overwrite Jira's date validation, but I think it will be easier to use a Free Text Field custom field that will hold the date as a string. Then, add to the field js code that will hide this field and copy it's date to the date field.
To keep the right order when searching for issues, you can either use date mapping to keep the georgian calendar up to date, or store the dates in a sortable way (for example YYYY/MM/DD/HH/MM - 201302161334) and order the results according to this field.
UPDATE
Simple example for Jira version 5.2.6, this will copy the text from field id customfield_10001 to the created field:
AJS.$("#create-date").text(AJS.$("#customfield_10001-val").text().trim())
To search easily keep another text field and save the date in the following format :
year month day hour minute
All in digits. for example, today's Gregorian date would be:
2013 02 267 10 26
than, when searching for issues, for example to find issues created after today's date:
custom_filed > "2013 02 267 10 26"
that sorting will work since it will sort issues first by year, than month, day, hour, minute.
I stored date in text field by creating new custom field in system-customfieldtypes-plugin.xml filed but In search it only accept exact text not > or <
custom_filed ~ "2013 02 267 10 26" It is acceptable but
custom_filed > "2013 02 267 10 26" shows jQL error.
using Delphi 2010 (Firebird [testing], MS Sql Server, Oracle [production])
The following is my SQL
SELECT p.script_no, MIN(p.start_Time) as startTime, MAX(p.end_Time) as endTime,
SUM(p.duration) as TotalDuration
FROM phase_times p
WHERE (p.script_no=:scriptNo) AND (Trunc(p.start_time) >= :beginDateRange) AND (Trunc(p.start_time) <= :endDateRange)
GROUP BY p.script_no
ParamByName('beginDateRange').AsDate:= Date - 30;
ParamByName('endDateRange').AsDate:= Date;
I am getting a "conversion error from string - 10-25-2012" and i am not sure why, since my datetime fields are in the "10/25/2012 9:20:49 AM" format in the database.
If i change it to the following : ParamByName('beginDateRange').AsString := formatDateTime('mm/dd/yyyy',Date - 30).....i get the error "conversion error from string - 10/25/2012"
reserching this error has provided me no new avenues, do you have any ideas?
According to the Interbase 6.0 manual, Embedded SQL guide, chapter 7, Firebird supports conversion from YYYY-MM-DD and YYYY-MM-DD HH:MM:SS.qqq. I also believe it supports American style shorthand dates (eg 1-JAN-2012) for conversion.
It may be there are some locale dependent conversion supported, but in general: use an actual date/timestamp type instead of a string.
UPDATE
I initially did not spot the TRUNC in your query: it is the cause of the conversion error as this function only works on numbers, see the manual entry for TRUNC.
Given your comment (and the respons of ain) I assume you are only interested in the date part, and want to ignore the time. If so, rewrite your use of TRUNC to:
CAST(<your-timestamp-field> AS DATE)
And the condition (Trunc(p.start_time) >= :beginDateRange) AND (Trunc(p.start_time) <= :endDateRange) to:
CAST(p.start_time AS DATE) BETWEEN :beginDateRange AND :endDateRange
Firebird doesn't support conversion from string to date and time value if string is in 12 hour format. Use 'dd.mm.yyyy hh:mm:ss' or 'mm/dd/yyyy hh:mm:ss' formats.
String to date/time conversions usually use user's locale.
So if you feed a date/time conversion function with string that does not match your date part of the locale - you will get similar errors.
Also specifying date/time values like "10/25/2012" is Locale dependent. So if you execute your program on a computer with different than US Locale (like Mine) - it's likely to fail if using "10/25/2012".
To be Locale independent I suggest two options:
Use StrToDateTime, specifying TFormatSettings
Use ISO 8601 for specifying date/time strings (but I don't think Delphi supports that...)
BTW programs like MS Sql, Excel etc. accept dates in ISO 8601. But you have to check this for FB.
Regarding this:
...since my datetime fields are in the "10/25/2012 9:20:49 AM" format in the database...
The internal storage of date/time fields varies between different DB Engines. What you see in your DB Management Software ("10/25/2012 9:20:49 AM" in your case) is the string representation of the data field, usually formatted (again) according your user Locale
if you connected with DB from Firebird 1.0 under the server Firebird 2.1 (for example) you need todo backup and restore under Firebird 2.1
I am using Delphi 7, and Titan BTrieve to open a Pervasive Table.
It is a TtbTable component.
I am trying to apply the filter on a TimeStamp field with my code as follows:
Date:=InputDate;
DateString:=FormatDateTime('DD/MM/YYYY HH:NN:SS', InputDate);
Table1.Filter:='UPDATEDON > '+chr(39)+DAteString+chr(39);
Table1.Filtered:=True;
The problem is that the filter results are incorrect. It returns records that are before the do not match the filter criteria.
the Table1.Filter, filters the data in TDataSet not in btrieve/pervasive.
the problem is the date in string format... you must use the formar YYYY-MM-DD and not DD-MM-YYYY because the string compare.
in a string compare 17-06-2012 is grater than 16-07-2012, (17>16)
From the look of it, you are comparing strings, not dates.
What version of PSQL are you using? Is the UPDATEDON field defined as a Timestamp in the Btrieve database? If it's a timestamp, values are stored in 8-byte unsigned values representing septaseconds (10^-7 second) since January 1, 0001 in a Gregorian calendar, Coordinated Universal Time (UTC). It is not stored as a string.
Btrieve / PSQL stores dates in the 'YYYY-MM-DD' format.
WHat does a value from the UPDATEDON field look like? To use it as a filter, you need to make sure the filter value looks the same.