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Record-level constraint definition
Source position: db.pas line 1047
type TCheckConstraint = class(TCollectionItem) |
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public |
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procedure Assign(); override; |
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Assign one constraint to another |
published |
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property CustomConstraint: string; [rw] |
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User-defined constraint |
property ErrorMessage: string; [rw] |
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Message to display when the constraint is violated |
property FromDictionary: Boolean; [rw] |
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True if the constraint is imported from a datadictionary |
property ImportedConstraint: string; [rw] |
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Constraint imported from the database engine |
end; |
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Record-level constraint definition |
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TCheckConstraint can be used to store the definition of a record-level constraint. It does not enforce the constraint, it only stores the constraint's definition. The constraint can come from several sources: an imported constraints from the database, usually stored in the TCheckConstraint.ImportedConstraint property , or a constraint enforced by the user on a particular dataset instance stored in TCheckConstraint.CustomConstraint
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Set of record-level constraints |
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Constraint imported from the database engine |
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User-defined constraint |