Delphi 7，Titan BTrieve组件

Question

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.

Answer 1

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)

Answer 2

从外观上看，您正在比较字符串，而不是日期。

Answer 3

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.