I think this means that you would do something like this: (the two changed lines are indicated)
{{-
config(
materialized = 'incremental',
incremental_strategy = 'merge',
unique_key = 'id',
post_hook = """
EXPORT DATA
OPTIONS (
uri = 'gs://bucket/path/{{ run_started_at.strftime('%Y-%m-%d_%H-%M-%S') }}/*.csv',
format = 'CSV',
overwrite = true,
header = true,
field_delimiter = ';')
AS (
/* this line is changed */
SELECT * FROM {{ this }} where loaded_at = {{ run_started_at }}
);
"""
)
-}}
SELECT *,
{{ run_started_at }} as loaded_at /* this line is changed*/
FROM {{ source('my_source', 'my_table') }}
WHERE
{%- if is_incremental() %}
date_hit > (SELECT MAX(date_hit) from {{ this }})
{%- else %}
date_hit >= "1970-01-01"
{% endif %}