Hi Benjie, for a point select (single value equality) like your query, MonetDB will build a hash index the first time such query is executed on a given column. The index is then kept as long as the server is running and there are no updates to that column. Thus, every follwing such query on the same column will benefit from the existing index. Best, Stefan On Thu, Jul 19, 2012 at 03:28:53PM -0400, Benjie Chen wrote:
Hi
From one big dataset, we already have 0.7 billion rows. And we are looking at having 100 datasets eventually over the period of a year. That's 70 billion rows. From what I understand, column data are loaded into virtual address space, then dynamically indexed for querying? Does that mean that on a query "SELECT a FROM table WHERE b = N", it'd have to load all of 70 billion values of b, index, then provide results for a? Is this a case where statically created index would help? Does MonetDB use static created index?
Thanks, Benjie
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