ftDateTime

ftDateTime = 11

Example

function IsDelphiDateTime(Field: TField): Boolean;
begin
  Result := Field.DataType = ftDateTime;
end;

Usage

ftDateTime identifies a combined date and time represented through Velox's timezone-free floating TDateTime serial value.

Additional Technical Info

ftDateTime is declaration ordinal 11 of TFieldType. Delphi maps it to TDateTimeField, whose value is an eight-byte TDateTime/Double serial: the integral part represents days around the Delphi epoch and the fraction represents time of day.

The value contains no timezone or UTC-offset flag. Whether it represents UTC, server local time, company local time or a timezone-free wall-clock value is an application/schema contract. Never perform timezone conversion solely because this enum is present. Record the interpretation separately and use explicit UTC/offset types at system boundaries.

Binary floating representation limits exact fractional precision. Database/provider precision can be lower and may round fractional seconds. Text assignment uses locale-sensitive StrToDateTime; an empty string clears the field. AsDateTime returns zero for Null, so use IsNull or AsVariant when the difference between Null and 1899-12-30 00:00:00 matters.

For higher-structure SQL values use ftTimeStamp; to retain an explicit offset use ftTimeStampOffset. Define an unambiguous output format rather than exporting field display text.

The example only inspects metadata and was source-reviewed; no clock, timezone, parsing, dataset, database, runtime or image test ran.

External references

• Embarcadero TFieldType, TDateTimeField and TDateTime.
• Free Pascal TFieldType and TDateTimeField compatibility references.

Created 2026-07-15