README.md in fluent-plugin-bigquery-0.5.0.beta1 vs README.md in fluent-plugin-bigquery-0.5.0.beta2

@@ -57,9 +57,10 @@
 | field_timestamp                        | string        | no                                           | no           | nil                                                                                                           | see examples.                                                                                                        |
 | replace_record_key                     | bool          | no                                           | no           | false                                                                                                         | see examples.                                                                                                        |
 | replace_record_key_regexp{1-10}        | string        | no                                           | no           | nil                                                                                                           | see examples.                                                                                                        |
 | convert_hash_to_json                   | bool          | no                                           | no           | false                                                                                                         | If true, converts Hash value of record to JSON String.                                                               |
 | insert_id_field                        | string        | no                                           | no           | nil                                                                                                           | Use key as `insert_id` of Streaming Insert API parameter.                                                            |
+| add_insert_timestamp                   | string        | no                                           | no           | nil                        | Adds a timestamp column just before sending the rows to BigQuery, so that buffering time is not taken into account. Gives a field in BigQuery which represents the insert time of the row.              |
 | allow_retry_insert_errors              | bool          | no                                           | false        | Retry to insert rows when an insertErrors occurs. There is a possibility that rows are inserted in duplicate. |
 | request_timeout_sec                    | integer       | no                                           | no           | nil                                                                                                           | Bigquery API response timeout                                                                                        |
 | request_open_timeout_sec               | integer       | no                                           | no           | 60                                                                                                            | Bigquery API connection, and request timeout. If you send big data to Bigquery, set large value.                     |
 | time_partitioning_type                 | enum          | no (either day)                              | no           | nil                                                                                                           | Type of bigquery time partitioning feature(experimental feature on BigQuery).                                        |
 | time_partitioning_expiration           | time          | no                                           | no           | nil                                                                                                           | Expiration milliseconds for bigquery time partitioning. (experimental feature on BigQuery)                           |