Appendix How to generate number or date sequences

271. How to generate number or date sequences

In this lesson, we’ll figure out how to generate a sequence of numbers or dates. In the course, we saw how handy it is to have such a helper table: if in some query we aggregate by date, for example, we might see a result like this:

date number_of_purchases
2020-01-01 12
2020-01-04 8
2020-01-12 9

What we really want, especially when plotting this data, is to have no missing dates in the output:

date number_of_purchases
2020-01-01 12
2020-01-02 0
2020-01-03 0
2020-01-04 8
2020-01-05 0

If we only have a table with a date...

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