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MissingSchemaAction Enumeration
Specifies the action to take when adding data to the DataSet and the required DataTable or DataColumn is missing.
Remarks
The MissingSchemaAction values are used whenever an action is taken that could change the schema of the DataSet.
Members
| Member Name | Description |
|---|---|
| Add | Adds the necessary columns to complete the schema. |
| AddWithKey | 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.
To function properly with the OLE DB .NET data Provider, 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 SQL Server™ .NET data Provider 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. See SQL Server™ Books Online for more information. |
| Error | A SystemException is generated. |
| Ignore | Ignores the extra columns. |
