I have a couple of websites generated from databases. Each has around half a million pages of unique content. The first one was indexed in like a week at 100K/d

I have a couple of websites generated from databases. Each has around half a million pages of unique content. The first one was indexed in like a week at 100K/day, almost instant tsunami of traffic. The second one is being indexed at 100-1000 pages per day, it's been years. Google works in mysterious ways.