[Overview][Constants][Types][Classes][Procedures and functions][Index] | Reference for unit 'db' (#fcl)

# TDataSet.FieldDefs

Definitions of available fields in the underlying database

## Declaration

Source position: db.pas line 1343

`public property TDataSet.FieldDefs: TFieldDefs read FFieldDefs write SetFieldDefs;`

## Description

FieldDefs is filled by the TDataset descendent when the dataset is opened. It represents the fields as they are returned by the particular database when the data is initially fetched from the engine. If the dataset uses dynamically created fields (when DefaultFields is True), then for each item in this list, a field i nstance will be created with default properties available in the field definition. If the dataset uses persistent fields, then the fields in the field list will be checked against the items in the FieldDefs property. If no matching item is found for a persistent field, then an exception will be raised. Items that exist in the fielddefs property but for which there is no matching field instance, are ignored.

## See also

TDataset.Open |  | Activate the dataset: Fetch data into memory.
TDataset.DefaultFields |  | Is the dataset using persisten fields or not.
TDataset.Fields |  | Indexed access to the fields of the dataset.

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