Verify BigQuery table existence

Your script is not entering the exception clause as it raises a NotFound error and not a HttpError.

This should work:

from google.cloud.exceptions import NotFound
def check_users_usersmetadata_existence():
    # (...)
    try:
        table = bigquery_client.get_table(table_ref)
        if table:
            print('Table {}\'s existence sucessfully proved!'.format(table_ref))
            return True
    except NotFound as error:
        # ...do some processing ...
        print('Whoops! Table {} doesn\'t exist here! Ref: {}'.format(table_ref, error.resp.status))
        return False

See the example in the official documentation of the BigQuery Python client: https://googleapis.dev/python/bigquery/latest/usage/tables.html#getting-a-table

Excerpt:

from google.cloud import bigquery
from google.cloud.exceptions import NotFound

client = bigquery.Client()
# table_id = "your-project.your_dataset.your_table"

try:
    client.get_table(table_id)  # Make an API request.
    print("Table {} already exists.".format(table_id))
except NotFound:
    print("Table {} is not found.".format(table_id))