Actian Community Blogs

Making people happy

So, the first thing to know is, data warehouse is supposed to make the end users happy. One could feel bad about being man in the middle, or even worse - the warehouse technical support, but this doesn't matter. It's the end user who has to be happy. So, happy about what? Well, if he gets answers he needs, we assume, he's happy. Nevertheless I would really like to make an opposition here. For example, "can I have some data about users that satisfy these conditions?"...

Until now, VectorWise's temporary queries results have to fit memory. Not always there is a possibility to rewrite the query in a "better" way (otherwise one could optimize infinitely to reach zero query time and no memory usage ). Consider an example, where one would like to count distinct users, which visit your website, but per day. Following the example, let's say Your website has been running for more than four years and You've got approximately from 7 to 13 millions of unique...

One can face a problem when migrating from MySQL to VectorWise, when a fast and appropriate method is required. Using multiple inserts is not the way VectorWise likes to see it, but using additional dumps can have a high storage cost.

I shall give here a hint, how to migrate large tables from MySQL to VectorWise using low disk space and memory usage. We'll use linux named pipes. First we have to create a pipe:

$ mknod my_pipe p

Now we make a query to...