Array timestamp not in standard format BigQuery

Question

I created a table in BigQuery and in one of the columns I specified its mode as a REPEATED (array) TIMESTAMP column, that is column4 .

CREATE OR REPLACE TABLE
  `project.dataset.table` ( column1 string,
    column2 TIMESTAMP,
    column3 ARRAY<int64>,
    column4 ARRAY<TIMESTAMP>)

When I insert data into that table, the column4 converts the CURRENT_TIMESTAMP() into the following format.

INSERT INTO
  `project.dataset.table` (column1,
    column2,
    column3,
    column4)
VALUES
  ("rowtest1", CURRENT_TIMESTAMP(), [5], [CURRENT_TIMESTAMP()])

In the same query I stated the CURRENT_TIMESTAMP() to Column2 and Column4 , but for Column4 it changed the format of CURRENT_TIMESTAMP() to 1660318705383274 instead 2022-08-12 15:38:25.383274 UTC .

I want to keep the format as in the Column2 2022-08-12 15:38:25.383274 UTC for both columns, is it possible?

I want to keep the column4 as REPEATED because I will use it as an updated_at field, to avoid redundancy in the table.

Answer 1

BigQuery UI seems to just display a timestamp value in an array as a format of unix timestamp. But internally, it still has a timestamp format in it.

See the query result as a JSON format.

SELECT [CURRENT_TIMESTAMP] ts;

And when you UNNEST an ARRAY<TIMESTAMP> , you can see it as a normal timestamp format like below.

SELECT ts FROM UNNEST([CURRENT_TIMESTAMP]) ts;