/// <summary>
/// Returns a data table containing column metadata of the reader.
/// </summary>
/// <returns>a DataTable containing column metadata.</returns>
public override DataTable GetSchemaTable()
{
DisposeCheck();
if (tables.Current == null)
{
return(null);
}
string projectId = bigQueryCommand.Connection.ProjectId;
string dataSetId = bigQueryCommand.Connection.DataSetId;
string tableId = tables.Current.TableReference.TableId;
DataTable dataTable = new DataTable {
TableName = tableId
};
dataTable.Columns.Add("ColumnName", typeof(string));
dataTable.Columns.Add("DataType", typeof(Type));
try {
Table tableSchema = bigQueryService.Tables.Get(projectId, dataSetId, tableId).Execute();
foreach (var tableFieldSchema in tableSchema.Schema.Fields)
{
dataTable.Rows.Add(tableFieldSchema.Name, BigQueryTypeConverter.ToType(tableFieldSchema.Type));
}
}
catch (GoogleApiException e) {
throw e.Wrap();
}
return(dataTable);
}
/// <summary>
/// Gets the type of the specified column.
/// </summary>
/// <param name="ordinal"> The ordinal number of a column.</param>
/// <returns>The type of the specified column.</returns>
public override Type GetFieldType(int ordinal) {
DisposeCheck();
RangeCheck(ordinal);
string type = schema.Fields[ordinal].Type;
Type fieldType = BigQueryTypeConverter.ToType(type);
if(fieldType != null)
return fieldType;
throw new ArgumentOutOfRangeException(nameof(ordinal), ordinal, "No field with ordinal");
}
object ChangeValueType(object value, int ordinal) {
if(value == null)
return null;
BigQueryDbType bigQueryType = BigQueryTypeConverter.ToBigQueryDbType(schema.Fields[ordinal].Type);
if(bigQueryType == BigQueryDbType.Timestamp) {
return UnixTimeStampToDateTime(value);
}
return Convert.ChangeType(value, BigQueryTypeConverter.ToType(schema.Fields[ordinal].Type), CultureInfo.InvariantCulture);
}
public void TimesTest(string bigQueryTypeName, Type systemType, BigQueryDbType bigQueryDbType, DbType dbType)
{
Assert.Equal(systemType, BigQueryTypeConverter.ToType(bigQueryTypeName));
Assert.Equal(bigQueryDbType, BigQueryTypeConverter.ToBigQueryDbType(bigQueryTypeName));
Assert.Equal(dbType, BigQueryTypeConverter.ToDbType(bigQueryDbType));
}
public void StringConvertTest(string stringType, Type systemType, BigQueryDbType bigQueryType)
{
Assert.Equal(systemType, BigQueryTypeConverter.ToType(stringType));
Assert.Equal(bigQueryType, BigQueryTypeConverter.ToBigQueryDbType(stringType));
}
public void TypeAndDbTypeTest(Type type1, DbType dbType, Type type2)
{
Assert.Equal(dbType, BigQueryTypeConverter.ToDbType(type1));
Assert.Equal(type2, BigQueryTypeConverter.ToType(dbType));
}
public void TypeAndBigQueryDbTypeTest(Type type1, BigQueryDbType bigQueryType, Type type2)
{
Assert.Equal(bigQueryType, BigQueryTypeConverter.ToBigQueryDbType(type1));
Assert.Equal(type2, BigQueryTypeConverter.ToType(bigQueryType));
}