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  • New SQL Down Under podcast episode: Bill Ramos

    - by DavidWimbush
    I thought Greg Lowe had stopped doing his excellent podcast a while back but every now and then I go and check (just in case). This time I found a new episode: http://www.sqldownunder.com/PreviousShows/tabid/98/Default.aspx. Great! As far as I can see, Greg just slipped this one out without any mention on his blog. I hope there are plenty more to come as there's no shortage of developments to discuss. It's funny to think that when I got into SQL Server, in 2000, one of the things I liked was that it only changed in occasional small increments. Really! This was a relief compared to keeping up with Visual Basic and Visual Studio (and .NET and C# and...). What happened? Did I miss a meeting? Still, I'm not complaining - there's no danger of getting bored!

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  • SQL In The City Charlotte - Fundamentals of Database Design

    - by drsql
    Next Monday, October 14, at Red-Gate's SQL In The City conference in Charlotte, NC (one day before PASS), I will be presenting my Fundamentals of Database Design session. It is my big-time chestnut session, the one that I do the most and have the most fun with. This will be the "single" version of the session, weighing in at just under an hour, and it is a lot of material to go over (even with no code samples to go awry to take up time.)  In this hour long session (presented in widescreen...(read more)

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  • SQL in Boston -- Red Gate Style

    - by Adam Machanic
    You might have heard of Red Gate's famous SQL in the City events: free, full-day educational events where you can learn from Red Gate's own evangelists in addition to various MVPs and other guests. With just a tiny bit of marketing thrown in for good measure (don't worry, it's not a daylong sales pitch). Red Gate is doing a US tour this fall, and I'm happy to note that my fair city of Boston is one of the stops ... and I am one of the speakers. The event takes place on October 8 . I'll be delivering...(read more)

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  • SQL Server 2012 edition comparison details are published

    - by DavidWimbush
    Interesting stuff, particularly if you're doing BI. BISM tabular and Power View will not be in Standard Edition, only in the new - presumably more expensive - Business Intelligence Edition. That kind of makes sense as you need a fairly pricey edition of SharePoint to really get all the benefits, but it's a shame there won't be some kind of limited version in Standard Edition. And Always On will be in Standard Edition but limited to 2 nodes. I really expected Always On to be Enterprise-only so this is a great decision. It allows those of us working at a more modest scale to benefit and raises the fault tolerance of SQL Server as a product to a new level.Read all about it here: http://www.microsoft.com/sqlserver/en/us/future-editions/sql2012-editions.aspx

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  • T-SQL Jokes

    - by Tomaz.tsql
    SQL Table walks to a psychiatrist dr. Index Table: "Doctor, I have a problem" Dr: "what kind a problem?" Table: "I'm a mess. I have things all over the place, i always look for my stuff" Dr. "No problem. I will get you in order". Index and table are reading a book "index-sutra" Table: Oh, baby tonight we can try a clustered position" Index: "yeah baby, we can also try covered position" Table: "or maybe multiple clustered position"...(read more)

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  • Annual SQL Server conference in Poland - SQLDay 2014

    - by Damian
    We had a great 3-days conference this year in Poland. The SQLDay (7th edition) is an annual community conference. We started in 2008 as a part of C2C (community to communities) conference and after that, from 2009 the SQLDay is the independent event dedicated to the SQL Server specialists. This year we had almost 300 people and speakers like Bob Ward, Klaus Aschenbrenner and Alberto Ferrari. Of course there were also many local Polish leaders (MVP's and an MCM :) )If you are curious how we played in Wroclaw this year - just visit the link http://goo.gl/cgNzDl (or try that one https://plus.google.com/photos/100738200012412193487/albums/6010410545898180113?authkey=CITqmqmkrKK8Tw) Visit the conference site: http://conference.plssug.org.pl/ 

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  • T-SQL Tuesday : Reflections on the PASS Summit and our community

    - by AaronBertrand
    Last week I attended the PASS Summit in Seattle. I blogged from both keynotes ( Keynote #1 and Keynote #2 ), as well as the WIT Luncheon - which SQL Sentry sponsored. I had a fantastic time at the conference, even though these days I attend far fewer sessions that I used to. As a company, we were overwhelmed by the positive energy in the Expo Hall. I really liked the notebook idea, where board members were assigned notebooks to carry around and take ideas from attendees. I took full advantage when...(read more)

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  • T-SQL User-Defined Functions: the good, the bad, and the ugly (part 1)

    - by Hugo Kornelis
    So you thought that encapsulating code in user-defined functions for easy reuse is a good idea? Think again! SQL Server supports three types of user-defined functions. Only one of them qualifies as good. The other two – well, the title says it all, doesn’t it? The bad: scalar functions A scalar user-defined function (UDF) is very much like a stored procedure, except that it always returns a single value of a predefined data type – and because of that property, it isn’t invoked with an EXECUTE statement,...(read more)

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  • In-Memory OLTP Sample for SQL Server 2014 RTM

    - by Damian
    I have just found a very good resource about Hekaton (In-memory OLTP feature in the SQL Server 2014). On the Codeplex site you can find the newest Hekaton samples - https://msftdbprodsamples.codeplex.com/releases/view/114491. The latest samples we have were related to the CTP2 version but the newest will work with the RTM version.There are some issues fixed you might find if you tried to run the previous samples on the RTM version:Update (Apr 28, 2014): Fixed an issue where the isolation level for sample stored procedures demonstrating integrity checks was too low. The transaction isolation level for the following stored procedures was updated: Sales.uspInsertSpecialOfferProductinmem, Sales.uspDeleteSpecialOfferinmem, Production.uspInsertProductinmem, and Production.uspDeleteProductinmem. 

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  • T-SQL User-Defined Functions: the good, the bad, and the ugly (part 1)

    - by Hugo Kornelis
    So you thought that encapsulating code in user-defined functions for easy reuse is a good idea? Think again! SQL Server supports three types of user-defined functions. Only one of them qualifies as good. The other two – well, the title says it all, doesn’t it? The bad: scalar functions A scalar user-defined function (UDF) is very much like a stored procedure, except that it always returns a single value of a predefined data type – and because of that property, it isn’t invoked with an EXECUTE statement,...(read more)

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  • T-SQL Tuesday : Reflections on the PASS Summit and our community

    - by AaronBertrand
    Last week I attended the PASS Summit in Seattle. I blogged from both keynotes ( Keynote #1 and Keynote #2 ), as well as the WIT Luncheon - which SQL Sentry sponsored. I had a fantastic time at the conference, even though these days I attend far fewer sessions that I used to. As a company, we were overwhelmed by the positive energy in the Expo Hall. I really liked the notebook idea, where board members were assigned notebooks to carry around and take ideas from attendees. I took full advantage when...(read more)

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  • In-Memory OLTP Sample for SQL Server 2014 RTM

    - by Damian
    I have just found a very good resource about Hekaton (In-memory OLTP feature in the SQL Server 2014). On the Codeplex site you can find the newest Hekaton samples - https://msftdbprodsamples.codeplex.com/releases/view/114491. The latest samples we have were related to the CTP2 version but the newest will work with the RTM version.There are some issues fixed you might find if you tried to run the previous samples on the RTM version:Update (Apr 28, 2014): Fixed an issue where the isolation level for sample stored procedures demonstrating integrity checks was too low. The transaction isolation level for the following stored procedures was updated: Sales.uspInsertSpecialOfferProductinmem, Sales.uspDeleteSpecialOfferinmem, Production.uspInsertProductinmem, and Production.uspDeleteProductinmem. 

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  • How SQL Saturday could be better

    - by AaronBertrand
    I've been to a lot of SQL Saturdays. They are great events to attend - from a community standpoint, from a learning standpoint, and from a speaker growth standpoint. Who could ask for more, right? Great sessions, from passionate speakers willing to both teach and learn, fantastic networking opportunities and lunch. All for free, or at a very low cost - some events need to recover costs and charge $10 for lunch. Still a phenomenal bargain IMHO. But we all know that these events aren't perfect... there...(read more)

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  • SQL Saturday #156 : Providence, RI

    - by AaronBertrand
    Well, East Greenwich, RI. Another successful event, this one put on by John Miner, Brandon Leach, Steve Simon, Scott Abrants and a host of other folks. Several #SQLFamily friends in attendance as well: Grant Fritchey, Mike Walsh, Jack Corbett, Wayne Sheffield and others. I gave a session in the morning and then a session to cap off the day. Thanks to everyone who attended! The downloads are here: T-SQL : Bad Habits & Best Practices The Ins & Outs of Contained Databases...(read more)

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  • SQL Server 2008 cluster freezing

    - by Ed Leighton-Dick
    We have run into a strange situation in which a SQL Server 2008 single-node cluster hangs. As background, we are rebuilding a Windows Server 2003/SQL Server 2005 two-node cluster using Windows 2008 and SQL Server 2008. Here's the timeline: Evicted the passive node (server B) from the Windows 2003/SQL 2005 cluster. The active node now functions as a single-node cluster with no problems. Wiped server B's disks and installed Windows 2008 and SQL Server 2008 as a single-node cluster. Since we do not want to the two clusters to communicate yet, we left the cluster's private network "heartbeat" adapter unconfigured. The cluster comes up and functions normally. Moved all databases to the new cluster. Cluster continues to function normally. Turned off server A (old cluster) in preparation for rebuilding as the second node of the new cluster. SQL Server instance on server B (new cluster) locks up, even though it should have no knowledge of or interaction with server A. Restarted server A. SQL Server instance on server B (new cluster) immediately begins working again. Things we have tried: The new cluster's name responds to ping and NETBIOS requests, even while the SQL Server is hung. We have confirmed that no IP address is assigned to the old heartbeat adapter, and it is not pulling an IP address from DHCP. Disabling the heartbeat's network card has the same effect. No errors were generated in any logs - Windows or SQL. When the error first occurred, it sat in the hung state for quite some time (well over 10 minutes) before anyone figured out what was going on. This would seem to eliminate any sort of normal cluster timeout in which it would have been searching for the other node (even if one had been configured). Server B is running Windows 2008 SP2, fully patched, and SQL Server 2008 SP1 CU7 (10.0.2775).

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  • SQL Server Express Failed to Install

    - by JasCav
    I am attempting to install SQL Server Express (as part of the Visual Studio 2010 Professional installation), but it is failing. I am receiving this error log. [06/22/11,16:31:39] Microsoft Visual Studio 2010 Professional - ENU: [2] UpdateFileFetcherFromMsi: Warning: Missing fwlink entry for cabinet: #SP.cab [06/22/11,16:31:40] setup.exe: [2] Duplicate module ID: {0AFE11CA-57AA-4F66-90BE-284F0F3A5ABD} [06/22/11,16:32:12] setup.exe: [2] Duplicate component in install order: SQL EULAs [06/22/11,16:32:12] setup.exe: [2] Duplicate component in install order: SQL EULAs [06/22/11,16:32:12] setup.exe: [2] Duplicate component in install order: SQL EULAs [06/22/11,17:07:55] Microsoft Visual Studio 2010 Professional - ENU: [2] UpdateFileFetcherFromMsi: Warning: Missing fwlink entry for cabinet: #SP.cab [06/22/11,17:07:55] setup.exe: [2] Duplicate module ID: {0AFE11CA-57AA-4F66-90BE-284F0F3A5ABD} [06/23/11,10:39:33] Microsoft Visual Studio 2010 Professional - ENU: [2] UpdateFileFetcherFromMsi: Warning: Missing fwlink entry for cabinet: #SP.cab [06/23/11,10:39:33] setup.exe: [2] Duplicate module ID: {0AFE11CA-57AA-4F66-90BE-284F0F3A5ABD} [06/23/11,10:40:22] setup.exe: [2] Duplicate component in install order: SQL EULAs [06/23/11,10:40:22] setup.exe: [2] Duplicate component in install order: SQL EULAs [06/23/11,10:40:22] setup.exe: [2] Duplicate component in install order: SQL EULAs [06/23/11,10:53:48] Microsoft Visual Studio 2010 Professional - ENU: [2] UpdateFileFetcherFromMsi: Warning: Missing fwlink entry for cabinet: #SP.cab [06/23/11,10:53:48] setup.exe: [2] Duplicate module ID: {0AFE11CA-57AA-4F66-90BE-284F0F3A5ABD} [06/23/11,13:19:26] Microsoft Visual Studio 2010 Professional - ENU: [2] UpdateFileFetcherFromMsi: Warning: Missing fwlink entry for cabinet: #SP.cab [06/23/11,13:19:26] setup.exe: [2] Duplicate module ID: {0AFE11CA-57AA-4F66-90BE-284F0F3A5ABD} [06/23/11,16:47:36] Microsoft SQL Server 2008 Express Service Pack 1 (x64): [2] Error code -2068643839 for this component is not recognized. [06/23/11,16:47:36] Microsoft SQL Server 2008 Express Service Pack 1 (x64): [2] Component Microsoft SQL Server 2008 Express Service Pack 1 (x64) returned an unexpected value. ***EndOfSession*** I'm reading various articles which point towards something being wrong in the register, but I can't find anything specific. Any suggestions for what I can do to fix this?

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  • Consolidate SQL Server Reporting Services

    - by Eric C. Singer
    I've been a big fan of consolidating as many DB's to a few SQL servers for a while and I've had great success with it. However, I've never had to deal with SQL reporting services. Has anyone migrated SSRS from a bunch of random SQL servers into a consolidated SQL server? I don't exactly know a whole lot about SSRS which is part of the problem. To my knowlege, it's one DB per SSRS instance, so it sounds like i'd need to find a way of exporting data and merging it. Basically the process used to look like: Move DB from SQL Express to shared SQL server Change point in APP to point at new SQL server With reporting services, how do I move the reporting service compenent of the DB as well? I realize I may need to tweak the app, but my question is on the SQL side.

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  • MS SQL to MySQL using MySQL Migration Toolkit: permission issue

    - by Zeno
    I have a MS SQL imported into SQL Server 2008 from a .bak and I set it to Mixed mode. I have a SQL user (called "test") that can correctly access the database using SQL Server. I need to convert this to a MySQL database, so I got the MySQL Migration Toolkit. I pick "MS SQL Server" and then it asks for the hostname/username/password/database. I'm not 100% sure on these, but I used "localhost" (running on same computer), left the port as is (1433) and the username/password ("test") for the SQL Server. And I used the database name for the SQL Server database I'm looking to import. I clicked next, enter my MySQL database details and then attempt to run it and I get this error: Connecting to source database and retrieve schemata names. Initializing JDBC driver ... Driver class MS SQL JDBC Driver Opening connection ... Connection jdbc:jtds:sqlserver://localhost:1433/Orders;user=test;password=blah;charset=utf-8;domain= The list of schema names could not be retrieved (error: 0). ReverseEngineeringMssql.getSchemata :Network error IOException: Connection refused: connect Details: net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java:372) net.sourceforge.jtds.jdbc.ConnectionJDBC3.<init>(ConnectionJDBC3.java:50) net.sourceforge.jtds.jdbc.Driver.connect(Driver.java:178) java.sql.DriverManager.getConnection(Unknown Source) java.sql.DriverManager.getConnection(Unknown Source) com.mysql.grt.modules.ReverseEngineeringGeneric.establishConnection(ReverseEngineeringGeneric.java:141) com.mysql.grt.modules.ReverseEngineeringMssql.getSchemata(ReverseEngineeringMssql.java:99) sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) java.lang.reflect.Method.invoke(Unknown Source) com.mysql.grt.Grt.callModuleFunction(Unknown Source)

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  • Connect over WiFi to SQL Server from another computer

    - by Bronzato
    I tried to connect over WiFi to SQL Server with SQL Server Management Studio from another computer, but it failed. I have a computer with Windows 7 & SQL Server 2008 (lets say the server computer). Next to it I have a freshly installed computer with Windows 7 & SQL Server Management Studio (let's say the client computer). What I did on the server computer: Configure firewall by enabling port 1433 Enabled network protocols (TCP/IP) inside SQL Server Configuration Manager Checked Allow remote connections to this server in server properties in the SQL Server Management application. Started SQL Server Browser Restarted services (SQL Server Browser is stopped at this point, but I don't think it is necessary. Is it?) Next, I successfully tested a ping on the port 1433 from my client computer with a tool named tcping (ex: tcping 192.168.1.4 1433). But I still cannot connect from my client computer to SQL Server on my server computer. Ok, something new with this problem: Until now, I successfully connected to my "server computer" with Management Studio. What I did is type the computer name in the server name field in the connection window of Management Studio. My previous (failed) attempt was to type the computer name followed by the instance of SQL server (ex: COMPUTER_NAME\SQL2008). I don't know why I only have to type the computer name. Now my new challenge is to be successful in connecting my VB6 application to this remote database located on my "server computer". I have a connection string for this but it failed to connect. Here is my connection string: "Provider=SQLOLEDB.1;Password=mypassword;User ID=sa;Initial Catalog=TPB;Data Source=THIERRY-HP\SQL2008" Any idea what's going wrong?

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  • Connect by Wifi to Sql Server from another computer

    - by Bronzato
    I try to connect by Wifi to Sql Server with Sql Server Management Studio from another computer but it failed. I have a computer with Windows Seven & Sql Server 2008 (lets say the server computer). Next to it, I have a fresh installed computer with Windows Seven & Sql Server Management Studio (let's say the client computer). What I do on the server computer: configure firewall by enabling port 1433 enabled network protocols (TCP/IP) inside Sql Server Configuration Manager checked "Allow remote connections to this server" on server properties in Sql Server Management. started Sql Server Browser restarted services (Sql Server Browser is stopped but I think it is not neccessary, isn't it?) Next, I successfully tested a ping on the port 1433 from my client computer with a tool named tcping (ex: tcping 192.168.1.4 1433). But I still cannot connect from my client computer to Sql Server on my other computer. Ok, something new on this problem: until now, I successfully connected to my "server computer" with Management Studio. What I do is typing the computer name in the server name field in the connection window of Management Studio. My previous (failed) attempt was to type the computer name followed by the instance of sql server (ex: COMPUTER_NAME\SQL2008). I don't know why I only have to type the computer name... Nevermind. Now my new challenge is to succeed connecting my VB6 application to this remote database located on my "computer server". I have a connection string for this but it failed to connect. Here is my connection string: "Provider=SQLOLEDB.1;Password=mypassword;User ID=sa;Initial Catalog=TPB;Data Source=THIERRY-HP\SQL2008" Any idea what's wrong? Thanks

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  • Unable to connect to remote MS SQL Server 2008 Express SP3 instance by name

    - by Max
    I am trying to connect to a remote MS SQL Server 2008 SP3 x86 Instance using it's name. At the first glance all seems to work well (e.g. it is possible to connect to the server locally and succesfully telnet it's port remotely), but there is a thing I can't understand... This line should connect us to the default instance of remote SQL Server: osql -S ServerIP -d MyDatabase /U sa -P MyPassword and it does the trick, however the next one: osql -S ServerIP\MyInstance -d MyDatabase /U sa -P MyPassword ends up with the following error: [SQL Native Client]SQL Network Interfaces: Error Locating Server/Instance Specified [xFFFFFFFF]. [SQL Native Client]Login timeout expired [SQL Native Client]An error has occurred while establishing a connection to the server. When connecting to SQL Server 2005, this failure may be caused by the fact that under the default settings SQL Server does not allow remote connections. The only instance running on the server is MyInstance, which is (I guess) the default one. Could you please put some time in explaining the issue.

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  • Oracle SQL Developer v3.2.1 Now Available

    - by thatjeffsmith
    Oracle SQL Developer version 3.2.1 is now available. I recommend that everyone now upgrade to this release. It features more than 200 bug fixes, tweaks, and polish applied to the 3.2 edition. The high profile bug fixes submitted by customers and users on our forums are listed in all their glory for your review. I want to highlight a few of the changes though, as I recognize many of you lack the time and/or patience to ‘read the docs.’ That would include me, which is why I enjoy writing these kinds of blog posts. I’m lazy – just like you! No more artificial line breaks between CREATE OR REPLACE and your PL/SQL In versions 3.2 and older, when you pull up your stored procedural objects in our editor, you would see a line break inserted between the CREATE OR REPLACE and then the body of your code. In version 3.2.1, we have removed the line break. 3.1 3.2.1 Trivia Did You Know? The database doesn’t store the ‘CREATE’ or ‘CREATE OR REPLACE’ bit of your PL/SQL code in the database. If we look at the USER_SOURCE view, we can see that the code begins with the object name. So the CREATE OR REPLACE bit is ‘artificial’ The intent is to give you the code necessary to recreate your object – and have it ‘compile’ into the database. We pretty much HAVE to add the ‘CREATE OR REPLACE.’ From now on it will appear inline with the first line of your code. Exporting Tables & Views When exporting data from your tables or views, previous versions of SQL Developer presented a 3 step wizard. It allows you to choose your columns and apply data filters for what is exported. This was kind of redundant. The grids already allowed you to select your columns and apply filters. Wouldn’t it be more intuitive AND efficient to just make the grids behave in a What You See Is What You Get (WYSIWYG) fashion? In version 3.2.1, that is exactly what will happen. The wizard now only has two steps and the grid will export the data and columns as defined in the visible grid. Let the grid properties define what is actually exported! And here is what is pasted into my worksheet: "BREWERY"|"CITY" "3 Brewers Restaurant Micro-Brewery"|"Toronto" "Amsterdam Brewing Co."|"Toronto" "Ball Brewing Company Ltd."|"Toronto" "Big Ram Brewing Company"|"Toronto" "Black Creek Historic Brewery"|"Toronto" "Black Oak Brewing"|"Toronto" "C'est What?"|"Toronto" "Cool Beer Brewing Company"|"Toronto" "Denison's Brewing"|"Toronto" "Duggan's Brewery"|"Toronto" "Feathers"|"Toronto" "Fermentations! - Danforth"|"Toronto" "Fermentations! - Mount Pleasant"|"Toronto" "Granite Brewery & Restaurant"|"Toronto" "Labatt's Breweries of Canada"|"Toronto" "Mill Street Brew Pub"|"Toronto" "Mill Street Brewery"|"Toronto" "Molson Breweries of Canada"|"Toronto" "Molson Brewery at Air Canada Centre"|"Toronto" "Pioneer Brewery Ltd."|"Toronto" "Post-Production Bistro"|"Toronto" "Rotterdam Brewing"|"Toronto" "Steam Whistle Brewing"|"Toronto" "Strand Brasserie"|"Toronto" "Upper Canada Brewing"|"Toronto" JUST what I wanted And One Last Thing Speaking of export, sometimes I want to send data to Excel. And sometimes I want to send multiple objects to Excel – to a single Excel file that is. In version 3.2.1 you can now do that. Let’s export the bulk of the HR schema to Excel, with each table going to it’s own workbook in the same worksheet. Select many tables, put them in in a single Excel worksheet If you try this in previous versions of SQL Developer it will just write the first table to the Excel file. This is one of the bugs we addressed in v3.2.1. Here is what the output Excel file looks like now: Many tables - Many workbooks in an Excel Worksheet I have a sneaky suspicion that this will be a frequently used feature going forward. Excel seems to be the cornerstone of many of our popular features. Imagine that!

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  • Installed Service Pack 3 for SQL Server 2005 but it does not show up when selecting @@version

    - by Blegger
    We installed Service Pack 3 for SQL Server 2005 Standard Edition (64-bit). In the Add or Remove Programs menu we have the following entries under Microsoft SQL Server 2005 (64-bit): Service Pack 3 for SQL Server Integration Services 64-bit) ENU (KB955706) Service Pack 3 for SQL Server Notification Services 2005 (64-bit) ENU (KB955706) Service Pack 3 for SQL Server Database Services 2005 (64-bit) ENU (KB955706) Service Pack 3 for SQL Server Tools and Workstation Components 2005 (64-bit) ENU (KB955706) But when I run the following query on the server: select @@version I get this result: Microsoft SQL Server 2005 - 9.00.4035.00 (X64) Nov 24 2008 16:17:31 Copyright (c) 1988-2005 Microsoft Corporation Standard Edition (64-bit) on Windows NT 5.2 (Build 3790: Service Pack 2) Why does it not display that it is running Service Pack 3?

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  • BNF – how to read syntax?

    - by Piotr Rodak
    A few days ago I read post of Jen McCown (blog) about her idea of blogging about random articles from Books Online. I think this is a great idea, even if Jen says that it’s not exciting or sexy. I noticed that many of the questions that appear on forums and other media arise from pure fact that people asking questions didn’t bother to read and understand the manual – Books Online. Jen came up with a brilliant, concise acronym that describes very well the category of posts about Books Online – RTFM365. I take liberty of tagging this post with the same acronym. I often come across questions of type – ‘Hey, i am trying to create a table, but I am getting an error’. The error often says that the syntax is invalid. 1 CREATE TABLE dbo.Employees 2 (guid uniqueidentifier CONSTRAINT DEFAULT Guid_Default NEWSEQUENTIALID() ROWGUIDCOL, 3 Employee_Name varchar(60) 4 CONSTRAINT Guid_PK PRIMARY KEY (guid) ); 5 The answer is usually(1), ‘Ok, let me check it out.. Ah yes – you have to put name of the DEFAULT constraint before the type of constraint: 1 CREATE TABLE dbo.Employees 2 (guid uniqueidentifier CONSTRAINT Guid_Default DEFAULT NEWSEQUENTIALID() ROWGUIDCOL, 3 Employee_Name varchar(60) 4 CONSTRAINT Guid_PK PRIMARY KEY (guid) ); Why many people stumble on syntax errors? Is the syntax poorly documented? No, the issue is, that correct syntax of the CREATE TABLE statement is documented very well in Books Online and is.. intimidating. Many people can be taken aback by the rather complex block of code that describes all intricacies of the statement. However, I don’t know better way of defining syntax of the statement or command. The notation that is used to describe syntax in Books Online is a form of Backus-Naur notatiion, called BNF for short sometimes. This is a notation that was invented around 50 years ago, and some say that even earlier, around 400 BC – would you believe? Originally it was used to define syntax of, rather ancient now, ALGOL programming language (in 1950’s, not in ancient India). If you look closer at the definition of the BNF, it turns out that the principles of this syntax are pretty simple. Here are a few bullet points: italic_text is a placeholder for your identifier <italic_text_in_angle_brackets> is a definition which is described further. [everything in square brackets] is optional {everything in curly brackets} is obligatory everything | separated | by | operator is an alternative ::= “assigns” definition to an identifier Yes, it looks like these six simple points give you the key to understand even the most complicated syntax definitions in Books Online. Books Online contain an article about syntax conventions – have you ever read it? Let’s have a look at fragment of the CREATE TABLE statement: 1 CREATE TABLE 2 [ database_name . [ schema_name ] . | schema_name . ] table_name 3 ( { <column_definition> | <computed_column_definition> 4 | <column_set_definition> } 5 [ <table_constraint> ] [ ,...n ] ) 6 [ ON { partition_scheme_name ( partition_column_name ) | filegroup 7 | "default" } ] 8 [ { TEXTIMAGE_ON { filegroup | "default" } ] 9 [ FILESTREAM_ON { partition_scheme_name | filegroup 10 | "default" } ] 11 [ WITH ( <table_option> [ ,...n ] ) ] 12 [ ; ] Let’s look at line 2 of the above snippet: This line uses rules 3 and 5 from the list. So you know that you can create table which has specified one of the following. just name – table will be created in default user schema schema name and table name – table will be created in specified schema database name, schema name and table name – table will be created in specified database, in specified schema database name, .., table name – table will be created in specified database, in default schema of the user. Note that this single line of the notation describes each of the naming schemes in deterministic way. The ‘optionality’ of the schema_name element is nested within database_name.. section. You can use either database_name and optional schema name, or just schema name – this is specified by the pipe character ‘|’. The error that user gets with execution of the first script fragment in this post is as follows: Msg 156, Level 15, State 1, Line 2 Incorrect syntax near the keyword 'DEFAULT'. Ok, let’s have a look how to find out the correct syntax. Line number 3 of the BNF fragment above contains reference to <column_definition>. Since column_definition is in angle brackets, we know that this is a reference to notion described further in the code. And indeed, the very next fragment of BNF contains syntax of the column definition. 1 <column_definition> ::= 2 column_name <data_type> 3 [ FILESTREAM ] 4 [ COLLATE collation_name ] 5 [ NULL | NOT NULL ] 6 [ 7 [ CONSTRAINT constraint_name ] DEFAULT constant_expression ] 8 | [ IDENTITY [ ( seed ,increment ) ] [ NOT FOR REPLICATION ] 9 ] 10 [ ROWGUIDCOL ] [ <column_constraint> [ ...n ] ] 11 [ SPARSE ] Look at line 7 in the above fragment. It says, that the column can have a DEFAULT constraint which, if you want to name it, has to be prepended with [CONSTRAINT constraint_name] sequence. The name of the constraint is optional, but I strongly recommend you to make the effort of coming up with some meaningful name yourself. So the correct syntax of the CREATE TABLE statement from the beginning of the article is like this: 1 CREATE TABLE dbo.Employees 2 (guid uniqueidentifier CONSTRAINT Guid_Default DEFAULT NEWSEQUENTIALID() ROWGUIDCOL, 3 Employee_Name varchar(60) 4 CONSTRAINT Guid_PK PRIMARY KEY (guid) ); That is practically everything you should know about BNF. I encourage you to study the syntax definitions for various statements and commands in Books Online, you can find really interesting things hidden there. Technorati Tags: SQL Server,t-sql,BNF,syntax   (1) No, my answer usually is a question – ‘What error message? What does it say?’. You’d be surprised to know how many people think I can go through time and space and look at their screen at the moment they received the error.

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  • Using SQL Execution Plans to discover the Swedish alphabet

    - by Rob Farley
    SQL Server is quite remarkable in a bunch of ways. In this post, I’m using the way that the Query Optimizer handles LIKE to keep it SARGable, the Execution Plans that result, Collations, and PowerShell to come up with the Swedish alphabet. SARGability is the ability to seek for items in an index according to a particular set of criteria. If you don’t have SARGability in play, you need to scan the whole index (or table if you don’t have an index). For example, I can find myself in the phonebook easily, because it’s sorted by LastName and I can find Farley in there by moving to the Fs, and so on. I can’t find everyone in my suburb easily, because the phonebook isn’t sorted that way. I can’t even find people who have six letters in their last name, because also the book is sorted by LastName, it’s not sorted by LEN(LastName). This is all stuff I’ve looked at before, including in the talk I gave at SQLBits in October 2010. If I try to find everyone who’s names start with F, I can do that using a query a bit like: SELECT LastName FROM dbo.PhoneBook WHERE LEFT(LastName,1) = 'F'; Unfortunately, the Query Optimizer doesn’t realise that all the entries that satisfy LEFT(LastName,1) = 'F' will be together, and it has to scan the whole table to find them. But if I write: SELECT LastName FROM dbo.PhoneBook WHERE LastName LIKE 'F%'; then SQL is smart enough to understand this, and performs an Index Seek instead. To see why, I look further into the plan, in particular, the properties of the Index Seek operator. The ToolTip shows me what I’m after: You’ll see that it does a Seek to find any entries that are at least F, but not yet G. There’s an extra Predicate in there (a Residual Predicate if you like), which checks that each LastName is really LIKE F% – I suppose it doesn’t consider that the Seek Predicate is quite enough – but most of the benefit is seen by its working out the Seek Predicate, filtering to just the “at least F but not yet G” section of the data. This got me curious though, particularly about where the G comes from, and whether I could leverage it to create the Swedish alphabet. I know that in the Swedish language, there are three extra letters that appear at the end of the alphabet. One of them is ä that appears in the word Västerås. It turns out that Västerås is quite hard to find in an index when you’re looking it up in a Swedish map. I talked about this briefly in my five-minute talk on Collation from SQLPASS (the one which was slightly less than serious). So by looking at the plan, I can work out what the next letter is in the alphabet of the collation used by the column. In other words, if my alphabet were Swedish, I’d be able to tell what the next letter after F is – just in case it’s not G. It turns out it is… Yes, the Swedish letter after F is G. But I worked this out by using a copy of my PhoneBook table that used the Finnish_Swedish_CI_AI collation. I couldn’t find how the Query Optimizer calculates the G, and my friend Paul White (@SQL_Kiwi) tells me that it’s frustratingly internal to the QO. He’s particularly smart, even if he is from New Zealand. To investigate further, I decided to do some PowerShell, leveraging the Get-SqlPlan function that I blogged about recently (make sure you also have the SqlServerCmdletSnapin100 snap-in added). I started by indicating that I was going to use Finnish_Swedish_CI_AI as my collation of choice, and that I’d start whichever letter cam straight after the number 9. I figure that this is a cheat’s way of guessing the first letter of the alphabet (but it doesn’t actually work in Unicode – luckily I’m using varchar not nvarchar. Actually, there are a few aspects of this code that only work using ASCII, so apologies if you were wanting to apply it to Greek, Japanese, etc). I also initialised my $alphabet variable. $collation = 'Finnish_Swedish_CI_AI'; $firstletter = '9'; $alphabet = ''; Now I created the table for my test. A single field would do, and putting a Clustered Index on it would suffice for the Seeks. Invoke-Sqlcmd -server . -data tempdb -query "create table dbo.collation_test (col varchar(10) collate $collation primary key);" Now I get into the looping. $c = $firstletter; $stillgoing = $true; while ($stillgoing) { I construct the query I want, seeking for entries which start with whatever $c has reached, and get the plan for it: $query = "select col from dbo.collation_test where col like '$($c)%';"; [xml] $pl = get-sqlplan $query "." "tempdb"; At this point, my $pl variable is a scary piece of XML, representing the execution plan. A bit of hunting through it showed me that the EndRange element contained what I was after, and that if it contained NULL, then I was done. $stillgoing = ($pl.ShowPlanXML.BatchSequence.Batch.Statements.StmtSimple.QueryPlan.RelOp.IndexScan.SeekPredicates.SeekPredicateNew.SeekKeys.EndRange -ne $null); Now I could grab the value out of it (which came with apostrophes that needed stripping), and append that to my $alphabet variable.   if ($stillgoing)   {  $c=$pl.ShowPlanXML.BatchSequence.Batch.Statements.StmtSimple.QueryPlan.RelOp.IndexScan.SeekPredicates.SeekPredicateNew.SeekKeys.EndRange.RangeExpressions.ScalarOperator.ScalarString.Replace("'","");     $alphabet += $c;   } Finally, finishing the loop, dropping the table, and showing my alphabet! } Invoke-Sqlcmd -server . -data tempdb -query "drop table dbo.collation_test;"; $alphabet; When I run all this, I see that the Swedish alphabet is ABCDEFGHIJKLMNOPQRSTUVXYZÅÄÖ, which matches what I see at Wikipedia. Interesting to see that the letters on the end are still there, even with Case Insensitivity. Turns out they’re not just “letters with accents”, they’re letters in their own right. I’m sure you gave up reading long ago, and really aren’t that fazed about the idea of doing this using PowerShell. I chose PowerShell because I’d already come up with an easy way of grabbing the estimated plan for a query, and PowerShell does allow for easy navigation of XML. I find the most interesting aspect of this as the fact that the Query Optimizer uses the next letter of the alphabet to maintain the SARGability of LIKE. I’m hoping they do something similar for a whole bunch of operations. Oh, and the fact that you know how to find stuff in the IKEA catalogue. Footnote: If you are interested in whether this works in other languages, you might want to consider the following screenshot, which shows that in principle, it should work with Japanese. It might be a bit harder to run this in PowerShell though, as I’m not sure how it translates. In Hiragana, the Japanese alphabet starts ?, ?, ?, ?, ?, ...

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