Given that most of the higher rep users here will be those who have time to spend answering questions, and who are well versed in database systems at a fundamental level, will also be consultants, I don't think it's fair that we say "oh, never link to your blog". I think it's entirely permissible that people here link to their blogs where they've already solved the problem.
HOWEVER, this is a Stack Exchange site, and as so, we all try to follow the same rules. Here's the biggest one in my own phrasing:
Every answer given should be able to stand on its own, even if that means the answer needs to be edited before being accepted. Answers which are not able to stand on their own, need to be edited or removed (or at the very least, downvoted to indicate that they are of poor quality).
What that means is:
Check my blog post to see how I solved that.
Is UNACCEPTABLE.
However, this would be perfectly cromulent: (if decidedly silly, because I didn't want to pick on any answer set, and instead wanted to be silly)
Check my blog post for the full breakdown on that problem, but here's what you need to know to solve this problem now. First, gather two large eggs from a chicken. Second, throw them at a passing car. Third, write "Google.com" in multicolored chalk on the auditorium roof.
Notice how we do link to the blog, but then we go on to give the concise bits of the answer? That's what's required if you're going to link to your own (or someone else's) blog.
If you feel that an off-the-shelf script or product is the best answer to the question, then by all means, explain why that particular tool is the best answer. This guideline holds true whether you're affiliated with the tool or not (as a salesperson, code author, support engineer, etc.) However, your answer needs to clearly articulate why the tool is the best answer, and if there's a price to the tool, that needs to be clearly explained as well. As with any answer, the more technical evidence that's present, the more likely it is that your answer will be upvoted and accepted. The less technical evidence, the more likely you'll be downvoted.