IsValidKeyDatatype Method
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The IsValidKeyDatatypemethod returns TRUE when the data type specified can participate in a PRIMARY KEY or FOREIGN KEY constraint.
語法
object
.IsValidKeyDatatype(
Type
, [ ReferencingType ] )
Parts
object
Expression that evaluates to an object in the Applies To list.Type
String that identifies a single base or user-defined data type by name.ReferencingType
Optional. A string that identifies a second base or user-defined data type by name.
Prototype (C/C++)
HRESULT IsValidKeyDatatype(
SQLDMO_LPCSTR szKeyColType,
LPBOOL pRetVal,
SQLDMO_LPCSTR szReferencingColType = NULL);
Returns
TRUE or FALSE as described in Remarks.
備註
When only the Type argument is used, the IsValidKeyDatatype method returns TRUE when a column defined using the data type can participate in a PRIMARY KEY constraint.
When a second data type is specified in the ReferencingType argument, the IsValidKeyDatatype method returns TRUE when the types are compatible. A TRUE return value indicates that a column defined using one data type could reference a column defined using the other data type in a FOREIGN KEY constraint.