Microsoft SQL Server
To avoid being too far behind you guys that are already upgrading to 11g, I’ve decided to invest on 11g during the Beta Program. This has been a lot of fun and I wish I can share some of my findings with you. For example, did you know that 11g can go faster without any change at all ? The queries here will illustrate the change made to the Nested Loop Algorithm in 11g :
n the following SQL*Plus output something is goofed up. You should not have a no rows selected with this SQL. When you see something like that for the first time, you can generally draw from four conclusions: Someone edited the output, SQL*Plus bug, Oracle bug, combination of the above. Since it was me who saw this, number one was an easy but irrelevant answer. What about an SQL*Plus bug? OK, run this using some other ad hoc tool. Same result. Time to take a more precise look at the problem. What is trans?
Let’s take the following question, for example. Is there any difference between using: where column between n and m and where column>=n and column<=m? Looks like a simple one, eh? hey are the same from a semantic point of view. But SQL is a declarative language. In other words, you wouldn’t expect same execution plan with two semantically identical statements, would you? There is at least one known (to me) example where both statement produce different execution plans. You never know until you test it. We start by creating a simple list-partitioned table with the local index:
I’ve updated and renamed my SQL*Developer Plug-in today ! Have a look.
I’ve just added 6 reports about RAC in the SQL*Developer Plug-In.
With the help of an anonymous friend, I’ve made available a new SQL*Developer Plug-In.
This article will discuss how to make many-to-many relationships in data warehousing easily queried by novice SQL users using point-and-click query tools.
I always get a chuckle well not always but often, when I read anything to do with Microsoft vs. “the flavour of the month”. In this case, it looks like the flavour of the month is Oracle. The articles simple imply that SQL Server is more secure than Oracle. They go on to count the number of vulnerabilities identified over the last few years. It’s scary stuff and I’m sure we’re all running out now to ask our architects and DBAs how quickly we can port over to SQL Server.
This first installment will deal with the biggest contributor to bad application design — the dreaded bad query. I’ve actually had busy systems crash because a developer unleashed a query that performed a full tablescan too many.
With the new dynamic performance views available in SQLserver 2005 you can run queries which allow you to determine these poor performers without much extra work. It is not statspack or Automatic Workload Repository (AWR) or V$ACTIVE_SESSION_HISTORY (more importantly) but it is a good start to determining what sql and what sessions are consuming the most resources in SQLserver 2005 instance.
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