Travel and busy-ness with my baby Destiny have prevented my posting this last installment in my list of top lessons learned at SQL PASS, but now here it is:
1. Buck Woody and Rob Farley are not only superstars in SQL technologies, they are talented as singer/songwriters too. Check out the video of the opening of the keynote session for proof. Cue it up at 00:02:27 to skip to the song. Their song was my favorite moment of the week.
2. On Wednesday I wrote that I wanted to learn more about Hadoop since it was part of a new feature of SQL Server 2012, and today I learned more about it than I really wanted to know, but the presentation by Dr. DeWitt was fascinating. Hadoop is a method of "divide and conquer" applied to massive amounts of unstructured (or more accurately loosely structured) data, the kind collected by websites such as Facebook, eBay, and Google.
3. If you add NOSPLASH after the path to SSMS executable in the shortcut properties, the application will open a few seconds faster. It does not seem like much, but it's a handy tip that I put in place right away.
4. If there are more than a couple of OR conjunctions in any given WHERE clause, using UNION ALL is probably a better approach. The query optimizer in SQL Server is much better at streamlining two or more small query conditions rather than one huge, complex one.
5. When possible, replace correlated subqueries in the SELECT clause with joins in the FROM clause. This is because the correlated subquery must execute once for every row in the main results, eliminating any optimization that is possible when the data are correlated in the FROM clause.
6. I learned how to create a "temporal snapshot fact table" for a data warehouse solution. This improves the efficiency of a "daily summary" fact table by using date ranges instead of individual days as the granularity level, ranges during which nothing changes in the data. I suspect this may come in handy when constructing fact tables for pledges and donations. It is definitely a nice concept to keep in the toolbox of report design.
7. I learned that the query optimizer can anticipate the best query plan even when part of the query statement has been "refactored" into a common table expression (CTE).
8. Thanks to Audrey Hammonds, I learned some great techniques for explaining CTEs effectively. I plan to use some of her presentation style and content ideas when I present an introduction to CTEs at SQL Saturday #96 in Washington, DC.
9. CROSS APPLY is comparable to an inner join and OUTER APPLY is comparable to a left join. In that same context, I learned that there is no difference in query efficiency to move a CROSS APPLY table valued expression into a correlated subquery within the SELECT clause. This is reassuring, since I have already made such a move with the FOR XML technique of turning row values into delimited strings.
10. Snow Crash by Neal Stephenson is a book I need to read. When Audrey referenced it in her presentation, about half the audience recognized it and praised it as a great read. She mentioned a few other books throughout her talk, but this one definitely stirred the strongest positive response.
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Showing posts with label SQL Server 2012. Show all posts
Showing posts with label SQL Server 2012. Show all posts
Tuesday, October 18, 2011
Friday, October 14, 2011
Top Ten Things I Learned at SQL Pass on 10/13/2011
The learning continues...
1. The "AlwaysOn" feature of SQL Server 2012 greatly simplifies high availability through redundant servers and simultaneously optimizes reporting by allowing you to use secondary servers for reporting and the primary server for transaction processing. However, it is currently unknown whether or not AlwaysOn will be in any edition other than Enterprise. It seems likely that it is an Enterprise-only feature.
2. The "ColumnStore Index" feature in SQL Server 2012 could radically speed up queries against tables in the Shelby v.5 database, especially attendance history. I can't wait to try it out. I may install Denali to try it out even before the official release of 2012.
3. There is a version of SQL Server Express coming out with 2012 that can easily be embedded into applications. This could potentially be a way to simplify the distribution of Shelby v.5 for those customers who do not own a license of SQL Server Standard. I will be looking into it more back home.
4. The "Semantic Model" features of SQL Server 2012, when coupled with the "FileTable" feature make for a powerful combination, capable of doing searches for document content based not just on matching of strings but actually pairing of concepts. I was blown away by the demo. Any librarian in the world would have been salivating over the processes and results I saw.
5. Two more times in one day I was shown the fallacy of putting dates inside of a function in the WHERE clause. I will never do it again, I promise! But I also learned that datetime and smalldatetime are being depricated in SS2012, meaning that we should probably start using the other, new data types for time. I will pass that info along to our database developers.
6. I learned that by simply changing the varchar data type to nvarchar, we could be capturing special characters for names, addresses, and more, which would make the v.5 database friendlier to international users. I'm going to do some testing on this when I get home too, to verify what is happening in our db right now when someone puts special characters into the varchar fields.
7. I need to kick the habit of not specifying the length of varchar values and others when I use them as variables. I've been snakebit by that one before, and what I learned today just reinforces that I need to specify length 100% of the time.
8. Some people, no matter how smart they are about what you want to discuss, can just be too annoying to talk to. It's just better to bide your time and find someone who may not be as knowledgeable but who is willing to listen and to converse at a pace that matches your own.
9. The 2013 Summit will be in Charlotte, NC. That will be much more convenient for me to attend, and I am very much looking forward to not having to adjust to a new time zone in order to participate.
10. Making free form reports with PowerPivot data in the background is not only possible, it allows for greater control over formatting and the embedding of elements such as sparklines into the data results. Free form reports can even use slicers to control the content. The only downside is the fixed nature of the rows and columns, which is why PivotTables are so handy in the first place.
1. The "AlwaysOn" feature of SQL Server 2012 greatly simplifies high availability through redundant servers and simultaneously optimizes reporting by allowing you to use secondary servers for reporting and the primary server for transaction processing. However, it is currently unknown whether or not AlwaysOn will be in any edition other than Enterprise. It seems likely that it is an Enterprise-only feature.
2. The "ColumnStore Index" feature in SQL Server 2012 could radically speed up queries against tables in the Shelby v.5 database, especially attendance history. I can't wait to try it out. I may install Denali to try it out even before the official release of 2012.
3. There is a version of SQL Server Express coming out with 2012 that can easily be embedded into applications. This could potentially be a way to simplify the distribution of Shelby v.5 for those customers who do not own a license of SQL Server Standard. I will be looking into it more back home.
4. The "Semantic Model" features of SQL Server 2012, when coupled with the "FileTable" feature make for a powerful combination, capable of doing searches for document content based not just on matching of strings but actually pairing of concepts. I was blown away by the demo. Any librarian in the world would have been salivating over the processes and results I saw.
5. Two more times in one day I was shown the fallacy of putting dates inside of a function in the WHERE clause. I will never do it again, I promise! But I also learned that datetime and smalldatetime are being depricated in SS2012, meaning that we should probably start using the other, new data types for time. I will pass that info along to our database developers.
6. I learned that by simply changing the varchar data type to nvarchar, we could be capturing special characters for names, addresses, and more, which would make the v.5 database friendlier to international users. I'm going to do some testing on this when I get home too, to verify what is happening in our db right now when someone puts special characters into the varchar fields.
7. I need to kick the habit of not specifying the length of varchar values and others when I use them as variables. I've been snakebit by that one before, and what I learned today just reinforces that I need to specify length 100% of the time.
8. Some people, no matter how smart they are about what you want to discuss, can just be too annoying to talk to. It's just better to bide your time and find someone who may not be as knowledgeable but who is willing to listen and to converse at a pace that matches your own.
9. The 2013 Summit will be in Charlotte, NC. That will be much more convenient for me to attend, and I am very much looking forward to not having to adjust to a new time zone in order to participate.
10. Making free form reports with PowerPivot data in the background is not only possible, it allows for greater control over formatting and the embedding of elements such as sparklines into the data results. Free form reports can even use slicers to control the content. The only downside is the fixed nature of the rows and columns, which is why PivotTables are so handy in the first place.
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