TADDataSet.ConstraintsEnabled Property

Specifies whether the dataset perform constraint checking.

Group

Links

TADDataSet Class, TADDataSet Members, uADCompDataSet Namespace, Example, public, See Also

Use ConstraintsEnabled to get / set the flag controlling automatic record-level constraints enforcement.

When ConstraintsEnabled is False (the default), the dataset does not check Constraints. This allows the dataset to perform the large data updates without overhead of checking constraints. When ConstraintsEnabled is True, the dataset checks Constraints at at end of data editing (Post / AppendRecord / InsertRecord).

If application needs to perform batch updates to dataset, then set ConstraintsEnabled to False before updates, and return to original value after updates. Also see BeginBatch / EndBatch methods.

Syntax

property ConstraintsEnabled: Boolean;

See Also

Constraints, BeginBatch, EndBatch, DisableConstraints, EnableConstraints, TDataSet.Post, TDataSet.AppendRecord, TDataSet.InsertRecord, TADUpdateOptions.CheckRequired

Example

var
  lPrevConsEnabled: Boolean;
...
lPrevConsEnabled := ADQuery1.ConstraintEnabled;
ADQuery1.ConstraintEnabled := False;
try
  // perform updates here, without checking client constraints
finally
  ADQuery1.ConstraintEnabled := lPrevConsEnabled;
end;

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