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.
Related
I have a G1 table (Gramex) in UI which has columns with date and time but as string.
When the user sorts the respective column with the help of inbuilt sort option, it sorts the data as string not as date.
Approach 1
The easiest way would be if the date and time were formatted like YYYY-MM-DD HH:MM:SS. For example, '2022-09-04 03:02:01'. This is a string that can be sorted consistently with the datetime.
You can create such strings in Python with the datetime.isoformat() function.
Approach 2
If your dates are stored in a different format, e.g. 04-09-2022, etc., then IF the data is loaded from a file, not a database, then you can modify the data with the function: transform to convert the column to the right data format.
For example:
url:
continent:
pattern: /data
handler: FormHandler
kwargs:
url: data.csv
function: data.assign(date_col=pd.to_datetime(data[date_col]).strftime('%Y-%m-%dT%H:%M:%S'))
This converts the date_col (replace this with your date column name) from any date format Pandas recognizes into a YYYY-MM-DD HH:MM:SS type format that is sortable.
If the data is loaded from a database, then you DO need to convert it into a sortable format first.
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
I am using the below query with date filtering, but I am getting wrong result.
SELECT * FROM TRANSACTIONSHISTORY
WHERE DATE > "29-01-2015 12:00:00"
AND DATE < "30-01-2015 00:00:00" AND USERID=abc
I am getting result with date column with value of 29-Jan-2016 records, what am I missing here, can any one help me to get out of this value.
The date format in your SQL will not work because SQLite doesn't have a native datetime type, so it's generally stored either as a string, in YYYY-MM-DD HH:MM:SS.SSS format, or as an numeric value representing the number of seconds since 1970-01-01 00:00:00 UTC. See date and time types on SQLite.org. Note that if you're using the string representation that the sequence is year, month, day (which, when sorting/querying this string field, the this alphanumeric string will sort correctly by year first, then month, and then day, which is critical when doing queries like yours).
If you really stored dates in the database as a string in the DD-MM-YYYY HH:MM:SS format, you should consider changing the format in which you saved the values into one of the approved date formats. It will make the date interactions with the database much, much easier, allowing queries like the one you asked for (though, obviously, with DD-MM-YYYY replaced with YYYY-MM-DD format).
You have cast your string to Date
SELECT * FROM TRANSACTIONSHISTORY WHERE DATE between Datetime('29-01-2015 12:00:00') and Datetime('30-01-2015 00:00:00') AND USERID=abc
The first answer is exactly what you need. What you did in your code would be comparing strings using ASCII values.
I would recommend you to use the linux time stamps like: 1453818208, which is easier to save and compare. In addition, it can always be translated to human-readable dates like: 29-01-2015 12:00:00.
SELECT * FROM TRANSACTIONSHISTORY
WHERE DATE > "29-01-2015 12:00:00"
AND DATE < "30-01-2015 00:00:00" AND USERID=abc
I hope this helps you :)
Try this first try without Time,after that try date and time both , Hope i will work for you
SELECT TRANSACTIONSHISTORY
FROM SHIPMENT
WHERE DATE
BETWEEN '11-15-2010'
AND '30-01-2015'
// you can try this one also
SELECT * FROM TRANSACTIONSHISTORY WHERE DATE BETWEEN "2011-01-11" AND "2011-8-11"
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'm trying to run the following db command against Informix:
delete from table1
where u_id in (select u_id
from table2
where c_id in (select c_id
from ptable
where name = 'Smith'
and dob = '29-08-1946'));
I pass this in as a string to the db.ExecuteNonQuery method in the MS Data Application block and I get the above error?
To get the date format '29-08-1946' to work, you need your DBDATE environment variable set to a value such as "DMY4-" (or "DMY4/"). These are standard variations for the UK (I used them for years; I now use "Y4MD-" exclusively, which matches both ISO 8601:2004 (Date formats) and ISO 9075 (SQL), except when debugging someone else's environment). There are other environment variables that can affect date formatting - quite a lot of them, in fact - but DBDATE takes priority over the others, so it is the big sledgehammer that fixes the problem.
One of the problems is that your notation using a plain string is not portable between US and UK (and ISO) settings of DBDATE. If you have a choice, the neutral constructor for dates is the MDY() function:
WHERE dob = MDY(8,29,1946)
This works regardless of the setting of DBDATE. You can probably use TO_DATE() too:
SELECT TO_DATE('29-08-1946', '%d-%m-%Y') FROM dual;
This generated '1946-08-29 00:00:00.00000' for me - the function generates a DATETIME YEAR TO FRACTION(5) value, but those convert reliably to DATE values in Informix.
You can also use the DATE() function or an explicit cast to DATE (either CAST('29-08-1946' AS DATE) or '29-08-1946'::DATE), but both of those are subject to the whims of the locale of the users.
Your date field is improperly formatted. Since there is no 29th month in the year 1946 that is what is causing the error.
I'd try just swapping the month and day. 08-29-1946.
The way the day and month parts of a date string are read in can depend on your computer's culture settings.
It is always safer to pass date strings to a database in the form 'dd-MMM-yyyy' (i.e. '29-aug-1946')
It's even safer to pass them as YYYY-MM-DD, the dd-MMM-yyyy in that example will fail on a server with a (for example) French locale.