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MissingSchemaAction Enum

Definition

Specifies the action to take when adding data to the DataSet and the required DataTable or DataColumn is missing.

public enum class MissingSchemaAction
public enum MissingSchemaAction
type MissingSchemaAction = 
Public Enum MissingSchemaAction
Inheritance
MissingSchemaAction

Fields

Name Value Description
Add 1

Adds the necessary columns to complete the schema.

Ignore 2

Ignores the extra columns.

Error 3

An InvalidOperationException is generated if the specified column mapping is missing.

AddWithKey 4

Adds the necessary columns and primary key information to complete the schema. For more information about how primary key information is added to a DataTable, see FillSchema(DataSet, SchemaType).

To function properly with the .NET Framework Data Provider for OLE DB, AddWithKey requires that the native OLE DB provider obtains necessary primary key information by setting the DBPROP_UNIQUEROWS property, and then determines which columns are primary key columns by examining DBCOLUMN_KEYCOLUMN in the IColumnsRowset. As an alternative, the user may explicitly set the primary key constraints on each DataTable. This ensures that incoming records that match existing records are updated instead of appended. When using AddWithKey, the .NET Framework Data Provider for SQL Server appends a FOR BROWSE clause to the statement being executed. The user should be aware of potential side effects, such as interference with the use of SET FMTONLY ON statements. For more information, see SET FMTONLY (Transact-SQL).

Remarks

The MissingSchemaAction values are used whenever an action is taken that could change the schema of the DataSet.

Applies to

See also