Add StackOverflow data

[tjpalmer]

[tjpalmer]

Here's a link for this:

https://console.cloud.google.com/bigquery?p=bigquery-public-data&d=stackoverflow&page=dataset

This might get the job done for question creation by quarter:

SELECT tags, extract(year FROM creation_date), extract(quarter FROM creation_date), count(*)  FROM `bigquery-public-data.stackoverflow.posts_questions`
group by tags, extract(year FROM creation_date), extract(quarter FROM creation_date)

It didn't like me sorting by year and quarter, though.