feat: add support for materialized views

[tswast]

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Fixes #407 🦕

[snippet-bot]

Here is the summary of changes.

You added 6 region tags.

• samples/snippets/materialized_view.py:17, tag bigquery_create_materialized_view
• samples/snippets/materialized_view.py:29, tag bigquery_create_materialized_view
• samples/snippets/materialized_view.py:45, tag bigquery_update_materialized_view
• samples/snippets/materialized_view.py:56, tag bigquery_update_materialized_view
• samples/snippets/materialized_view.py:73, tag bigquery_delete_materialized_view
• samples/snippets/materialized_view.py:83, tag bigquery_delete_materialized_view

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[shollyman]

Minor naming ruminations, and a paste edit for the license header.

Thanks for putting this together!

[shollyman]

I wonder if we can use a better prefix? For logical views we're already using view_ prefix, maybe mview or matview? My worry that mv is too terse here and/or people will overlook them in favor of the logical properties.

[shollyman]

nit: s/view/materialized view/ since we're dealing with multiple kinds now.

[shollyman]

This tag makes me itchy, and expecting a DDL style ALTER MATERIALIZED VIEW statement rather than an api update call. Should we correct the tag?

[tswast]

Agreed, corrected to bigquery_update_materialized_view.

The corresponding docs section has room for both. https://cloud.google.com/bigquery/docs/materialized-views#alter For example the bq table shows bq query with DDL and bq update options.

[shollyman]

2020?