Adds DataTables to a DataSet and configures the schema to match the schema in the data source.
DataTable[ ] FillSchema( DataSet dataSet, SchemaType schemaType )
DataTable[ ] FillSchema( DataSet dataSet, SchemaType schemaType, string srcTable )
DataTable FillSchema( DataTable dataTable, SchemaType schemaType )
dataSet: A DataSet to fill with records and, optionally, schema.
schemaType: One of the SchemaType values that specify how to insert the schema.
srcTable: The name of the source table to use for table mapping.
For Syntax 1 and 2, the return value is a reference to a collection of DataTable objects that were added to the DataSet. For Syntax 3, the return value is a reference to a DataTable.
“Obtaining AseDataAdapter schema information” and .NET Framework help.