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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"A system test for load_table_from_datarame() consistently fails on master branch","articleBody":"A system test `test_load_table_from_dataframe_w_explicit_schema()` consistently fails on the latest `master` branch, both under Python 2.7 and Python 3.8 (example [Kokoro run](https://source.cloud.google.com/results/invocations/0db81847-def8-4d23-be0e-446b4855ad7f/targets/cloud-devrel%2Fclient-libraries%2Fpython%2Fgoogleapis%2Fpython-bigquery%2Fpresubmit%2Fpresubmit/log)). It is also consistently reproducible locally.\r\n\r\n```\r\n...\r\ngoogle.api_core.exceptions.BadRequest: 400 Error while reading data, error message: Invalid datetime value -62135596800000000 for field 'dt_col' of type 'INT64' (logical type 'TIMESTAMP_MICROS'): generic::out_of_range: Cannot return an invalid datetime value of -62135596800000000 microseconds relative to the Unix epoch. The range of valid datetime values is [0001-01-1 00:00:00, 9999-12-31 23:59:59.999999]\r\n```\r\n\r\nTicket in the Google issue tracker: https://issuetracker.google.com/issues/151765076","author":{"url":"https://github.com/plamut","@type":"Person","name":"plamut"},"datePublished":"2020-03-17T10:31:35.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":14},"url":"https://github.com/61/python-bigquery/issues/61"}