I doubt it means the site was under construction. I don't think any legitimate web developer out there would prefer error messages over a redirect notification page saying the site was down for maintenance. Besides, it was database errors, which means the site was functional but it had a problem accessing the database where all the data is stored.
Their other forum City Data has issues all the time because so many people use it and obviously Advameg hasn't done much in the way of building or hosting on a better infrastructure to handle it. I wouldn't be surprised if the same was true for this site. We do get quite a lot of traffic, particularly on the guest side of things.
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