Conor vs. SQL

Loading Data into SQL

Conor Cunningham [MSFT] — Fri, 05 Feb 2010 14:38:05 GMT

(I didn’t write this, so no Conor vs. today, folks :) http://msdn.microsoft.com/en-us/library/dd425070.aspx This is a good read on the various ways to load lots of data into SQL Server. Enjoy! Conor...(read more)

Conor vs. Data Warehouses (an introduction)

Conor Cunningham [MSFT] — Fri, 29 Jan 2010 22:36:15 GMT

I received this question from an internal (as in within Microsoft but not in the SQL Server team) user of SQL Server. The basic question has to do with how you set up a data warehouse and whether one should or should not create foreign keys in a...(read more)

Conor vs. His Schedule

Conor Cunningham [MSFT] — Fri, 29 Jan 2010 21:49:38 GMT

I apologize for those of you who have outstanding questions in my inbox. I have been quite busy at work these days working on what I think are awesome features for a future release of SQL Server. I resolve to be better in answering your mails...(read more)

Conor vs. “Does Join Order Matter?”

Conor Cunningham [MSFT] — Thu, 10 Dec 2009 18:38:29 GMT

I got this question/claim again this week, so I’ll write a blog post on it while I wait for my build to complete: It usually goes something like “When I rewrite my query, SQL Server gives me a different plan. Therefore, I should rewrite all my queries...(read more)

Conor vs. FOREIGN KEY join elimination

Conor Cunningham [MSFT] — Thu, 12 Nov 2009 15:45:23 GMT

I received a question from a friend in Brazil related to foreign keys and join elimination in SQL Server. Yes, SQL Server can detect that some joins are not needed to return results to the user and skip them. What is this evil magic, you ask? ...(read more)

Conor vs. Windows 7

Conor Cunningham [MSFT] — Tue, 27 Oct 2009 13:55:49 GMT

(Not a SQL Server post) I have been meaning to install Windows 7, and I got around to doing it last night. I usually run Windows 2003/8 Server for work, so my interest in the consumer side is perhaps not as high as some others. Nevertheless,...(read more)

Conor vs. UNIQUE in Index Definitions

Conor Cunningham [MSFT] — Wed, 21 Oct 2009 16:18:50 GMT

I gave a talk to the Austin-area PASS group last night on B-Tree indexing in SQL Server, and I received a question about whether to make clustered indexes UNIQUE or not (assuming the data is unique on the key columns). The expectation was that this...(read more)

Conor vs. Statement Offsets

Conor Cunningham [MSFT] — Thu, 13 Aug 2009 17:15:25 GMT

As most of you have figured out by now, I work mostly on queries :). One of the things that I often need to do is to get a statement out of a batch so that I can go look more closely at a query plan (and, in my case, the code that generates it). ...(read more)

Server Cursors

Conor Cunningham [MSFT] — Thu, 13 Aug 2009 16:58:40 GMT

My coworker Marc posted up a good introduction into the different server cursor models and you can see it here: http://blogs.msdn.com/sqlqueryprocessing/archive/2009/08/12/understanding-sql-server-fast-forward-server-cursors.aspx...(read more)

Conor vs. Stats NORECOMPUTE

Conor Cunningham [MSFT] — Thu, 13 Aug 2009 16:52:54 GMT

It’s been a busy summer. I got back from vacation and have been hard at work on new features for a future version of SQL Server. You can always still send me questions about the existing product, of course, and I will answer them here (conorc...(read more)

Conor vs. Dynamic SQL vs. Procedures vs. Plan Quality for Parameterized Queries

Conor Cunningham [MSFT] — Thu, 04 Jun 2009 01:39:02 GMT

I received a question from a customer today about query plan choice for a parameterized query - specifically that different plans get picked based on where the plan is located, and sometimes one might be better than another. Apparently, for their...(read more)

Conor vs. Recompiles, part 2

Conor Cunningham [MSFT] — Mon, 25 May 2009 21:39:25 GMT

Thanks to those of you who replied to my previous post. I spent the last week or so talking with customers, coworkers, and looking at various applications to see how recompiles are modeled today in their applications. At a high level, SQL...(read more)

Conor vs. Recompiles

Conor Cunningham [MSFT] — Mon, 18 May 2009 21:45:03 GMT

I have a question for you guys about how do you force a recompile for a single query today? There are a lots of different ways that one could cause the system to recompile a query: a) sp_recompile <object used in a query> b)DBCC FREEPROCCACHE...(read more)

Do Filtered Statistics update as frequently as normal statistics?

Conor Cunningham [MSFT] — Sat, 18 Apr 2009 07:01:40 GMT

I received a question this week about whether filtered statistics update as frequently as regular statistics. The right way to ask the question is “Do filtered statistics become invalid as frequently as regular statistics?”, as stats are recomputed...(read more)

SQL Server 2008 Internals Book Now Available!

Conor Cunningham [MSFT] — Mon, 23 Mar 2009 17:28:05 GMT

For those of you waiting for the new "Inside SQL Server" book, it is actually out now. Kalen decided to give it a name change, and the actual title is "SQL Server 2008 Internals". I've written a chapter on how the Query...(read more)