Rails - Saving Daily Metrics

Question

I'm currently developing a Rails application, on top of PostgreSQL, that stores daily data for our company. We run ads on Facebook, and we have a few hundred ads running at any one time. I pull metrics every day, and import to my application, which then either creates or updates based on if it exists. However, I want to be able to see daily performance over the course of, say a week or month. What would be the easiest way to accomplish this?

My facebook_ad model has X amount of rows, 1 for each ad campaign. Each column denotes a specific metric, ie amount spent, clicks, etc. Should I create a new table for each date? Is there a way to timestamp every entry and include the time in my queries? I've made good progress up until here, and no amount of searching has brought me to a strategy I could use. Side note, we are hoping to access to their API, which would probably solve most of this. But we want to build something in the interim, so we can be as efficient as possible until then, which could be 6 months or more.

Edited::

I want to query and graph the data based on the daily data. For example, grab the metrics from 10/01/14 - 10/08/14 for one ad, and be able to see 10/01/14: MetricA = 1, MetricB = 2; 10/02/14: MetricA = 4, MetricB = 5; 10/03/14: MetricA = 6, Metric B = 3, etc. We want to be able to see trends and see how changes affect performance.

Answer 1

I would definitely not recommend creating a new table for each date -- that would be a data management nightmare. There shouldn't be any reason you can't have each ad campaign in the same table based on what you've said above. You could have a created and updated column in the table which defaults to now() , and if you update it for any reason, set the updated column to now() again. (I like to add those columns to just about every table I create -- it's often useful for a variety of queries).

You could then query that table based on the desired timeframe to get your performance statistics. Depending upon the exact nature of what you want to query, Window Functions may prove to be quite useful.