feat: Feature/list tables page size

[OmriBromberg]

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Fixes #173 🦕

Hey guys, I explained in the issue a bit but I wanted to implement it so users would be able to change max_results @ dataset.list_tables like the arraysize parameter so I copied how it is treated in the parse_url area and updated the tests and docs for it, the new parameter for it is called list_tables_page_size

also I saw that on line 606
there is this expression self.arraysize = self.arraysize or arraysize which always takes the default arraysize instead of the parsed querystring arraysize because self.arraysize is always initialized to a default value, so I also reversed it to be as so self.arraysize = arraysize or self.arraysize, now the querystring arraysize will take precedence over the default value

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[OmriBromberg]

@googlebot I signed it!

[jimfulton]

This is a great start. In addition to adding a feature, you found two bugs!

This needs test of the logic that fetches lists of tables. A unit test would be fine and should be straightforward to write.

[OmriBromberg]

hey, regarding this can you explain this logic to me? why shouldn't it always take the "full_table_id" property? gives us inconsistencies

[jimfulton]

hey, regarding this can you explain this logic to me? why shouldn't it always take the "full_table_id" property? gives us inconsistencies

That's a good question.

If you look at: https://github.com/sqlalchemy/sqlalchemy/blob/b20b6f8fe7ea0198f819a0fd68ca076b6c760054/lib/sqlalchemy/testing/suite/test_reflection.py#L537-L579

SQLAlchemy expects the results to be unqualified, which we satisfy if we have a schema.

Looking at other dialects:

MS SQL requires a schema: https://github.com/sqlalchemy/sqlalchemy/blob/b20b6f8fe7ea0198f819a0fd68ca076b6c760054/lib/sqlalchemy/dialects/mssql/base.py#L2877

Oracle assumes there's a default: https://github.com/sqlalchemy/sqlalchemy/blob/b20b6f8fe7ea0198f819a0fd68ca076b6c760054/lib/sqlalchemy/dialects/oracle/base.py#L1759-L1760

as does Postgres: https://github.com/sqlalchemy/sqlalchemy/blob/b20b6f8fe7ea0198f819a0fd68ca076b6c760054/lib/sqlalchemy/dialects/postgresql/base.py#L3488-L3490

As does sqlite, sort of: https://github.com/sqlalchemy/sqlalchemy/blob/b20b6f8fe7ea0198f819a0fd68ca076b6c760054/lib/sqlalchemy/dialects/sqlite/base.py#L1977-L1981

and so on.

So BQ is a little different because there might not be a default.

Amongst the options:

1. Error if no schema is provided and there's no default.
2. Qualify the results if we don't have a schema. I prefer using just the data set id in this case. full_table_id adds clutter IMO.

---

Playing with this some more, you can list schemas in other projects by specifying project_id.schema_id (e.g. "bigquery-public-data.census_bureau_acs"). That makes the use of a colon in full_table_id a little weird.

[jimfulton]

The bigquery client now accepts a page_size parameter, so this PR wants to use that.

When your;re ready for me to review, please merge master to get rid of many spurious changes. :)

[jimfulton]

Thanks!