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  • C -- Basic Struct questions

    - by Ryan Yu
    So I'm trying to learn C right now, and I have some basic struct questions I'd like to clear up: Basically, everything centers around this snippet of code: #include <stdio.h> #include <stdlib.h> #define MAX_NAME_LEN 127 typedef struct { char name[MAX_NAME_LEN + 1]; unsigned long sid; } Student; /* return the name of student s */ const char* getName (const Student* s) { // the parameter 's' is a pointer to a Student struct return s->name; // returns the 'name' member of a Student struct } /* set the name of student s If name is too long, cut off characters after the maximum number of characters allowed. */ void setName(Student* s, const char* name) { // 's' is a pointer to a Student struct | 'name' is a pointer to the first element of a char array (repres. a string) s->name = name; } /* return the SID of student s */ unsigned long getStudentID(const Student* s) { // 's' is a pointer to a Student struct return s->sid; } /* set the SID of student s */ void setStudentID(Student* s, unsigned long sid) { // 's' is a pointer to a Student struct | 'sid' is a 'long' representing the desired SID s->sid = sid; } I've commented up the code in an attempt to solidify my understanding of pointers; I hope they're all accurate. So anyway, I have a feeling that setName and setStudentID aren't correct, but I'm not exactly sure why. Can someone explain? Thanks!

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  • Is there a way to prevent SQL Server silently truncating data in local variables and stored procedure parameters?

    - by Luke Woodward
    I recently encountered an issue while porting an app to SQL Server. It turned out that this issue was caused by a stored procedure parameter being declared too short for the data being passed to it: the parameter was declared as VARCHAR(100) but in one case was being passed more than 100 characters of data. What surprised me was that SQL Server didn't report any errors or warnings -- it just silently truncated the data to 100 characters. The following SQLCMD session demonstrates this: 1 create procedure WhereHasMyDataGone (@data varchar(5)) as 2 begin 3 print 'Your data is ''' + @data + '''.'; 4 end; 5 go 1 exec WhereHasMyDataGone '123456789'; 2 go Your data is '12345'. Local variables also exhibit the same behaviour: 1 declare @s varchar(5) = '123456789'; 2 print @s; 3 go 12345 Is there an option I can enable to have SQL Server report errors (or at least warnings) in such situations? Or should I just declare all local variables and stored procedure parameters as VARCHAR(MAX) or NVARCHAR(MAX)?

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  • Finding out the windows group by virtue of which a user is able to access a database in sql server?

    - by Raghu Dodda
    There is a SQL Server 2005 database with mixed-mode authentication. Among others, we have the following logins on the server: our-domain\developers-group-1, and our-domain\developers-group-2 which are AD groups. The our-domain\developer-group-2 is added to the sysadmin role on the server, by virture of which all domain users of that group can access any database as SQL Server implictly maps the sysadmin role to the dbo user in each database. There are two users our-domain\good-user and our-domain\bad-user The issue is the following: Both the good-user and the bad-user have the exact same AD group memberships. They are both members of our-domain\developers-group-1 and our-domain\developers-group-2. The good-user is able to access all the databases, and the bad-user is not. The bad-user is able to login, but he is unable access any databases. By the way, I am the good-user. How do I go about finding out why? Here's what I tried so far: When I do print current_user, I get dbo When I do print system_user, I get my-domain\good-user When I do select * from fn_my_permissions(NULL, 'SERVER'), I see permissions. But if do execute as user='my-domain\good-user'; select * from fn_my_permissions(NULL, 'SERVER'), I dont see any permisisons. And When I do, execute as user='my-domain\bad-user'; select * from fn_my_permissions(NULL, 'SERVER'), I dont see any permisisons. Also, I was wondering if there is a sql command that will tell me, "hey! the current database user is able to access this database because he is a member such-and-such ad-group, which is a login that is mapped to such-and-such user in this database".

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  • How to pass XML from C# to a stored procedure in SQL Server 2008?

    - by Geetha
    I want to pass xml document to sql server stored procedure such as this: CREATE PROCEDURE BookDetails_Insert (@xml xml) I want compare some field data with other table data and if it is matching that records has to inserted in to the table. Requirements: How do I pass XML to the stored procedure? I tried this, but it doesn’t work:[Working] command.Parameters.Add( new SqlParameter("@xml", SqlDbType.Xml) { Value = new SqlXml(new XmlTextReader(xmlToSave.InnerXml, XmlNodeType.Document, null)) }); How do I access the XML data within the stored procedure? Edit: [Working] String sql = "BookDetails_Insert"; XmlDocument xmlToSave = new XmlDocument(); xmlToSave.Load("C:\\Documents and Settings\\Desktop\\XML_Report\\Books_1.xml"); SqlConnection sqlCon = new SqlConnection("..."); using (DbCommand command = sqlCon.CreateCommand()) { **command.CommandType = CommandType.StoredProcedure;** command.CommandText = sql; command.Parameters.Add( new SqlParameter("@xml", SqlDbType.Xml) { Value = new SqlXml(new XmlTextReader(xmlToSave.InnerXml , XmlNodeType.Document, null)) }); sqlCon.Open(); DbTransaction trans = sqlCon.BeginTransaction(); command.Transaction = trans; try { command.ExecuteNonQuery(); trans.Commit(); sqlCon.Close(); } catch (Exception) { trans.Rollback(); sqlCon.Close(); throw; } Edit 2: How to create a select query to select pages, description based on some conditions. <booksdetail> <isn_13>700001048</isbn_13> <isn_10>01048B</isbn_10> <Image_URL>http://www.landt.com/Books/large/00/7010000048.jpg</Image_URL> <title>QUICK AND FLUPKE</title> <Description> PRANKS AND JOKES QUICK AND FLUPKE </Description> </booksdetail>

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  • Is there a free tool which can help visualize the logic of a stored procedure in SQL Server 2008 R2?

    - by Hamish Grubijan
    I would like to be able to plot a call graph of a stored procedure. I am not interested in every detail, and I am not concerned with dynamic SQL (although it would be cool to detect it and skip it maybe or mark it as such.) I would like the tool to generate a tree for me, given the server name, db name, stored proc name, a "call tree", which includes: Parent stored procedure. Every other stored procedure that is being called as a child of the caller. Every table that is being modified (updated or deleted from) as a child of the stored proc which does it. Hopefully it is clear what I am after; if not - please do ask. If there is not a tool that can do this, then I would like to try to write one myself. Python 2.6 is my language of choice, and I would like to use standard libraries as much as possible. Any suggestions? EDIT: For the purposes of bounty Warning: SQL syntax is COMPLEX. I need something that can parse all kinds of SQL 2008, even if it looks stupid. No corner cases barred :) EDIT2: I would be OK if all I am missing is graphics.

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  • What are your best practices for ensuring the correctness of the reports from SQL?

    - by snezmqd4
    Part of my work involves creating reports and data from SQL Server to be used as information for decision. The majority of the data is aggregated, like inventory, sales and costs totals from departments, and other dimensions. When I am creating the reports, and more specifically, I am developing the SELECTs to extract the aggregated data from the OLTP database, I worry about mistaking a JOIN or a GROUP BY, for example, returning incorrect results. I try to use some "best practices" to prevent me for "generating" wrong numbers: When creating an aggregated data set, always explode this data set without the aggregation and look for any obvious error. Export the exploded data set to Excel and compare the SUM(), AVG(), etc, from SQL Server and Excel. Involve the people who would use the information and ask for some validation (ask people to help to identify mistakes on the numbers). Never deploy those things in the afternoon - when possible, try to take a look at the T-SQL on the next morning with a refreshed mind. I had many bugs corrected using this simple procedure. Even with those procedures, I always worry about the numbers. What are your best practices for ensuring the correctness of the reports?

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  • Still some questions about USB

    - by b-gen-jack-o-neill
    Hi, few days ago I asked here about implementing USB. Now, If I may, would like to ask few more questions, about thing I dind´t quite understood. So, first, If I am right, Windows has device driver for USB interface, for the physical device that sends and receives communication. But what this driver offers to system (user)? I mean, USB protocol is made so its devices are adressed. So you first adress device than send message to it. But how sophisticted is the device controller (HW) and its driver? Is it so sophisticated that it is a chip you just send device adress and data, and it writes the outcomming data out and incomming data to some internal register to be read, or thru DMA directly to memory? Or, how its drivers (SW) really work? Does its driver has some advanced functions like send _data to _device? Becouse I somewhat internally hope there is a way to directly send some data thru USB, maybe by calling USB drivers itself? Is there any good article, tutorial you know about to really explain how all this logic works? Thanks.

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  • jqgrid questions

    - by user508518
    Hi All- I recently posted a question on SO on freezing columns in jqgrid(http://stackoverflow.com/questions/4586924/jqgrid-freeze-columns). I got the following solution to be working in IE8, but its not all perfect: I set to use two css classes, one for header and other one for the rows like below: .jqgridbodyLock{ position:relative; left: expression(parentNode.parentNode.parentNode.parentNode.parentNode.scrollLeft); z-index: 10; } .jqgridheaderLocked{ position:relative; left: expression(parentNode.parentNode.parentNode.parentNode.parentNode.scrollLeft); /* IE5+ only */ z-index:30; } Then in colModel, I used the property classes {name:'column1', width:100, index:'column1', sorttype:"string", classes:'jqgridbodyLock'},//lock the body row and to lock the respective header I used code as below: $("#grid").setLabel("column1","column1","jqgridheaderLocked"); Though the solution works, I have the following problems: 1) The header values shake a lot when scrolling to the right though they remain frozen 2) The body values of the frozen column disappear when the cursor is taken out of the grid. 3) How to lock a normal table in firefox. I see that 'expression' is exclusive only to IE browser Thanks a lot

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  • I have data about deadlocks, but I can't understand why they occur (MS SQL/ASP.NET MVC)

    - by Alex
    I am receiving a lot of deadlocks in my big web application. http://stackoverflow.com/questions/2941233/how-to-automatically-re-run-deadlocked-transaction-asp-net-mvc-sql-server Here I wanted to re-run deadlocked transactions, but I was told to get rid of the deadlocks - it's much better, than trying to catch the deadlocks. So I spent the whole day with SQL profiler, setting the tracing keys etc. And this is what I got. There's a Users table. I have a very high usable page with the following query (it's not the only query, but it's the one that causes troubles) UPDATE Users SET views = views + 1 WHERE ID IN (SELECT AuthorID FROM Articles WHERE ArticleID = @ArticleID) And then there's the following query in ALL pages: User = DB.Users.SingleOrDefault(u => u.Password == password && u.Name == username); That's where I get User from cookies. Very often a deadlock occurs and this second LINQ TO SQL query is chosen as a victim, so it's not run, and users of my site see an error screen. I read a lot about deadlocks... And I don't understand why this is causing a deadlock. So obviously both of this queries run very often. At least once a second. Maybe even more often (300-400 users online). So they can be run at the same time very easily, but why does it cause a deadlock? Please help. Thank you

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  • What is the best way to embed SQL in VB.NET.

    - by Amy P
    I am looking for information on the best practices or project layout for software that uses SQL embedded inside VB.NET or C#. The software will connect to a full SQL DB. The software was written in VB6 and ported to VB.NET, we want to update it to use .NET functionality but I am not sure where to start with my research. We are using Visual Studio 2005. All database manipulations are done from VB. Update: To clarify. We are currently using SqlConnection, SqlDataAdapter, SqlDataReader to connect to the database. What I mean by embed is that the SQL stored procedures are scripted inside our VB code and then run on the db. All of our tables, stored procs, views, etc are all manipulated in the VB code. The layout of our code is quite messy. I am looking for a better architecture or pattern that we can use to organize our code. Can you recommend any books, webpages, topics that I can google, etc to help me better understand the best way for us to do this.

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  • finding middle element of an array

    - by senthil
    Hi all, I came cross a question in my interview. Question: Array of integers will be given as the input and you should find out the middle element when sorted , but without sorting. For Example. Input: 1,3,5,4,2 Output: 3 When you sort the given input array, it will be 1,2,3,4,5 where middle element is 3. You should find this in one pass without sorting. Any solutions for this?

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  • C vs C++ function questions

    - by james
    I am learning C, and after starting out learning C++ as my first compiled language, I decided to "go back to basics" and learn C. There are two questions that I have concerning the ways each language deals with functions. Firstly, why does C "not care" about the scope that functions are defined in, whereas C++ does? For example, int main() { donothing(); return 0; } void donothing() { } the above will not compile in a C++ compiler, whereas it will compile in a C compiler. Why is this? Isn't C++ mostly just an extension on C, and should be mostly "backward compatible"? Secondly, the book that I found (Link to pdf) does not seem to state a return type for the main function. I check around and found other books and websites and these also commonly do not specify return types for the main function. If I try to compile a program that does not specify a return type for main, it compiles fine (although with some warnings) in a C compiler, but it doesn't compile in a C++ compiler. Again, why is that? Is it better style to always specify the return type as an integer rather than leaving it out? Thanks for any help, and just as a side note, if anyone can suggest a better book that I should buy that would be great!

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  • Questions about shifting from mysql to PDO

    - by Scarface
    Hey guys I have recently decided to switch all my current plain mysql queries performed with php mysql_query to PDO style queries to improve performance, portability and security. I just have some quick questions for any experts in this database interaction tool Will it prevent injection if all statements are prepared? (I noticed on php.net it wrote 'however, if other portions of the query are being built up with unescaped input, SQL injection is still possible' I was not exactly sure what this meant). Does this just mean that if all variables are run through a prepare function it is safe, and if some are directly inserted then it is not? Currently I have a connection at the top of my page and queries performed during the rest of the page. I took a look at PDO in more detail and noticed that there is a try and catch procedure for every query involving a connection and the closing of that connection. Is there a straightforward way to connecting and then reusing that connection without having to put everything in a try or constantly repeat the procedure by connecting, querying and closing? Can anyone briefly explain in layman's terms what purpose a set_exception_handler serves? I appreciate any advice from any more experienced individuals.

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  • Why Create Mock Objects?

    - by Chris
    During a recent interview I was asked why one would want to create mock objects. My answer went something like, "Take a database--if you're writing test code, you may not want that test hooked up live to the production database where actual operations will be performed." Judging by response, my answer clearly was not what the interviewer was looking for. What's a better answer?

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  • A debbugging test, suggestions needed.

    - by flash
    I am having a debugging test, as part of an interview.. I thought if any one can help with the approach, when I am faced with a large code base and have to find bugs inside that within an hour or two.This is going to be Core java based app (I guess) on Eclipse 3.2+

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  • Questions about "sets"

    - by James
    I have a test tomorrow that I am revising for and the lecturer has supplied some sample questions with no answers. I was hoping I could get some help with a couple of them. I've written what I think the answer is for them. 1. What is the type of the set {1, 2, 3}? integer/number 2. What is the type of the set {{1}, {2}, {3}}? integer/number (unsure what putting each number in {} does?) 3. What is the type of the set {{1}, {2}, {3}, empty}? integer/number 4. What is the type of the set {1, {2}, 3}? — is it well typed? integer/number 5. What is the type of the set {1, 2, john}? — is it well typed? unsure for a mixed set. Taking a complete guess of void or empty. Any help will be much appreciated.

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  • Is it possible to submit data into a SQL database, wait for that to finish, and then return the ID g

    - by user322478
    I have an ASP form that needs to submit data to two different systems. First the data needs to go into an MS SQL database, which will get an ID. I then need to submit all that form data to an external system, along with that ID. Pretty much everything in the code works just fine, the data goes into the database, and the data will go to the external system. The problem is I am not getting my ID back from SQL when I execute that query. I am under the impression this is happening because of how fast everything occurs in the code. The database is adding it's row at the same time my post page runs it's query to get the ID back, I think. I need to know of a way to wait until SQL finished the insert or wait for a specific amount of time maybe. I already tried using the hacks to "sleep" with ASP, that did not help. I am sure I could accomplish this in .Net, my background is more .Net than ASP, but this is what I have to work with on my current project. Any ideas?

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  • “I could use a little help here” or “I can do it myself, thank you” for Cloud Projects

    - by BuckWoody
    Windows Azure allows you to write code in languages within the .NET stack, you can use Java, C++, PHP, NodeJS and others. Code is code - other than keeping things stateless, using a Web or Worker Role in Azure is not all that different from working with an on-premises system. However…. Working in a scalable, component-based stateless architecture that can use federated security is not all that common for many developers. Some are used to owning the server, scaling up, and state-full paradigms that have a single security domain. Making the transition whilst trying to create a new software application or even port a previous one can be daunting. Sure, we have absolutely tons of free training, kits, videos, online books and more to learn on your own, but some things like architecture can be pivotal as you move along. So the question is, should you just strike out on your own for a Cloud project, or get Microsoft Consulting Services or another partner to work with you on your first one? I use a few decision points to help guide the projects I assist in. Note: I’m a huge fan of having help that ends up giving you training and leaves you in charge. If you do engage with someone to help you, make sure you keep this clear and take more and more ownership yourself as the project progresses. How much time do you have? Usually the first thing I ask is about the timeline for the project. It doesn’t matter how skilled you are, if you have a short window to get things done it’s better to get help - especially if this is your first cloud project. Having someone that knows the platform well can save you amazing amounts of time. If you have longer, then start with the training in the link above and once you feel confident, jump in. How complex is the project? If there are a lot of moving parts, it’s best to engage a partner. The reason is that certain interactions - particularly things like Service Bus or Data Integration  - can be quite different than what you may have encountered before. How many people do you have? I have a “pizza rule” about projects I’ve used in my career - if it takes over two pizzas to feed everyone on the project, it’s too big and will fail. That being said, one developer and a one-week deadline does not a good project make, usually. It’s best to have at least one architect (or someone in that role) guiding the project along, and at least two developers to work on a cloud project. That’s a generalization of course, since I’ve seen great software on Azure with one developer writing code all by herself, but for more complex projects, more (to a point) is better. The nice thing about bringing on a partner is that you don’t have to hire them full time - they help you and then they go away. How critical is the project? There’s no shame in using some help. If the platform is new, if the project is large and complex, and if it is critical to the business, you should engage a partner. That’s regardless of Cloud or anything else - get some help. You don’t want to hit your company’s bottom line in a negative way, but you have to innovate and get them a competitive advantage. Do your research, make sure the partner is qualified to help you, and get it done. Don’t let these questions scare you off. There are lots of projects you can implement on Windows and SQL Azure with nothing other than the Software Development Kit (SDK) that you get for free with Windows Azure. And assistance comes in many forms - sometimes just phone support, a friend you can ask. Microsoft Consulting Services or any of our great partners. You can get help on just the architecture piece or have them show you how to write the code. They’ll get involved as little or as much as you like.

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  • Archiving SQLHelp tweets

    - by jamiet
    #SQLHelp is a Twitter hashtag that can be used by any Twitter user to get help from the SQL Server community. I think its fair to say that in its first year of being it has proved to be a very useful resource however Kendra Little (@kendra_little) made a very salient point yesterday when she tweeted: Is there a way to search the archives of #sqlhelp Trying to remember answer to a question I know I saw a couple months ago http://twitter.com/#!/Kendra_Little/status/15538234184441856 This highlights an inherent problem with Twitter’s search capability – it simply does not reach far enough back in time. I have made steps to remedy that situation by putting into place two initiatives to archive Tweets that contain the #sqlhelp hashtag. The Archivist http://archivist.visitmix.com/ is a free service that, quite simply, archives a history of tweets that contain a given search term by periodically polling Twitter’s search service with that search term and subsequently displaying a dashboard providing an aggregate view of those tweets for things like tweet volume over time, top users and top words (Archivist FAQ). I have set up an archive on The Archivist for “sqlhelp” which you can view at http://archivist.visitmix.com/jamiet/7. Here is a screenshot of the SQLHelp dashboard 36 minutes after I set it up: There is lots of good information in there, including the fact that Jonathan Kehayias (@SQLSarg) is the most active SQLHelp tweeter (I suspect as an answerer rather than a questioner ) and that SSIS has proven to be a rather (ahem) popular subject!! Datasift The Archivist has its uses though for our purposes it has a couple of downsides. For starters you cannot search through an archive (which is what Kendra was after) and nor can you export the contents of the archive for offline analysis. For those functions we need something a bit more heavyweight and for that I present to you Datasift. Datasift is a tool (currently an alpha release) that allows you to search for tweets and provide them through an object called a Datasift stream. That sounds very similar to normal Twitter search though it has one distinct advantage that other Twitter search tools do not – Datasift has access to Twitter’s Streaming API (aka the Twitter Firehose). In addition it has access to a lot of other rather nice features: It provides the Datasift API that allows you to consume the output of a Datasift stream in your tool of choice (bring on my favourite ultimate mashup tool J ) It has a query language (called Filtered Stream Definition Language – FSDL for short) A Datasift stream can consume (and filter) other Datasift streams Datasift can (and does) consume services other than Twitter If I refer to Datasift as “ETL for tweets” then you may get some sort of idea what it is all about. Just as I did with The Archivist I have set up a publicly available Datasift stream for “sqlhelp” at http://datasift.net/stream/1581/sqlhelp. Here is the FSDL query that provides the data: twitter.text contains "sqlhelp" Pretty simple eh? At the current time it provides little more than a rudimentary dashboard but as Datasift is currently an alpha release I think this may be worth keeping an eye on. The real value though is the ability to consume the output of a stream via Datasift’s RESTful API, observe: http://api.datasift.net/stream.xml?stream_identifier=c7015255f07e982afdeebdf1ae6e3c0d&username=jamiet&api_key=XXXXXXX (Note that an api_key is required during the alpha period so, given that I’m not supplying my api_key, this URI will not work for you) Just to prove that a Datasift stream can indeed consume data from another stream I have set up a second stream that further filters the first one for tweets containing “SSIS”. That one is at http://datasift.net/stream/1586/ssis-sqlhelp and here is the FSDL query: rule "414c9845685ff8d2548999cf3162e897" and (interaction.content contains "ssis") When Datasift moves beyond alpha I’ll re-assess how useful this is going to be and post a follow-up blog. @Jamiet

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  • T-SQL Tuesday #005 : SSRS Parameters and MDX Data Sets

    - by blakmk
    Well it this weeks  T-SQL Tuesday #005  topic seems quite fitting. Having spent the past few weeks creating reports and dashboards in SSRS and SSAS 2008, I was frustrated by how difficult it is to use custom datasets to generate parameter drill downs. It also seems Reporting Services can be quite unforgiving when it comes to renaming things like datasets, so I want to share a couple of techniques that I found useful. One of the things I regularly do is to add parameters to the querys. However doing this causes Reporting Services to generate a hidden dataset and parameter name for you. One of the things I like to do is tweak these hidden datasets removing the ‘ALL’ level which is a tip I picked up from Devin Knight in his blog: There are some rules i’ve developed for myself since working with SSRS and MDX, they may not be the best or only way but they work for me. Rule 1 – Never trust the automatically generated hidden datasets Or even ANY, automatically generated MDX queries for that matter.... I’ve previously blogged about this here.   If you examine the MDX generated in the hidden dataset you will see that it generates the MDX in the context of the originiating query by building a subcube, this mean it may NOT be appropriate to use this in a subsequent query which has a different context. Make sure you always understand what is going on. Often when i’m developing a dashboard or a report there are several parameter oriented datasets that I like to manually create. It can be that I have different datasets using the same dimension but in a different context. One example of this, is that I often use a dataset for last month and a dataset for the last 6 months. Both use the same date hierarchy. However Reporting Services seems not to be too smart when it comes to generating unique datasets when working with and renaming parameters and datasets. Very often I have come across this error when it comes to refactoring parameter names and default datasets. "an item with the same key has already been added" The only way I’ve found to reliably avoid this is to obey to rule 2. Rule 2 – Follow this sequence when it comes to working with Parameters and DataSets: 1.    Create Lookup and Default Datasets in advance 2.    Create parameters (set the datasets for available and default values) 3.    Go into query and tick parameter check box 4.    On dataset properties screen, select the parameter defined earlier from the parameter value defined earlier. Rule 3 – Dont tear your hair out when you have just renamed objects and your report doesn’t build Just use XML notepad on the original report file. I found I gained a good understanding of the structure of the underlying XML document just by using XML notepad. From this you can do a search and find references of the missing object. You can also just do a wholesale search and replace (after taking a backup copy of course ;-) So I hope the above help to save the sanity of anyone who regularly works with SSRS and MDX.   @Blakmk

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  • Using Deployment Manager

    - by Jess Nickson
    One of the teams at Red Gate has been working very hard on a new product: Deployment Manager. Deployment Manager is a free tool that lets you deploy updates to .NET apps, services and databases through a central dashboard. Deployment Manager has been out for a while, but I must admit that even though I work in the same building, until now I hadn’t even looked at it. My job at Red Gate is to develop and maintain some of our community sites, which involves carrying out regular deployments. One of the projects I have to deploy on a fairly regular basis requires me to send my changes to our build server, TeamCity. The output is a Zip file of the build. I then have to go and find this file, copy it across to the staging machine, extract it, and copy some of the sub-folders to other places. In order to keep track of what builds are running, I need to rename the folders accordingly. However, even after all that, I still need to go and update the site and its applications in IIS to point at these new builds. Oh, and then, I have to repeat the process when I deploy on production. Did I mention the multiple configuration files that then need updating as well? Manually? The whole process can take well over half an hour. I’m ready to try out a new process. Deployment Manager is designed to massively simplify the deployment processes from what could be lots of manual copying of files, managing of configuration files, and database upgrades down to a few clicks. It’s a big promise, but I decided to try out this new tool on one of the smaller ASP.NET sites at Red Gate, Format SQL (the result of a Red Gate Down Tools week). I wanted to add some new functionality, but given it was a new site with no set way of doing things, I was reluctant to have to manually copy files around servers. I decided to use this opportunity as a chance to set the site up on Deployment Manager and check out its functionality. What follows is a guide on how to get set up with Deployment Manager, a brief overview of its features, and what I thought of the experience. To follow along with the instructions that follow, you’ll first need to download Deployment Manager from Red Gate. It has a free ‘Starter Edition’ which allows you to create up to 5 projects and agents (machines you deploy to), so it’s really easy to get up and running with a fully-featured version. The Initial Set Up After installing the product and setting it up using the administration tool it provides, I launched Deployment Manager by going to the URL and port I had set it to run on. This loads up the main dashboard. The dashboard does a good job of guiding me through the process of getting started, beginning with a prompt to create some environments. 1. Setting up Environments The dashboard informed me that I needed to add new ‘Environments’, which are essentially ways of grouping the machines you want to deploy to. The environments that get added will show up on the main dashboard. I set up two such environments for this project: ‘staging’ and ‘live’.   2. Add Target Machines Once I had created the environments, I was ready to add ‘target machine’s to them, which are the actual machines that the deployment will occur on.   To enable me to deploy to a new machine, I needed to download and install an Agent on it. The ‘Add target machine’ form on the ‘Environments’ page helpfully provides a link for downloading an Agent.   Once the agent has been installed, it is just a case of copying the server key to the agent, and the agent key to the server, to link them up.   3. Run Health Check If, after adding your new target machine, the ‘Status’ flags an error, it is possible that the Agent and Server keys have not been entered correctly on both Deployment Manager and the Agent service.     You can ‘Check Health’, which will give you more information on any issues. It is probably worth running this regardless of what status the ‘Environments’ dashboard is claiming, just to be on the safe side.     4. Add Projects Going back to the main Dashboard tab at this point, I found that it was telling me that I needed to set up a new project.   I clicked the ‘project’ link to get started, gave my new project a name and clicked ‘Create’. I was then redirected to the ‘Steps’ page for the project under the Projects tab.   5. Package Steps The ‘Steps’ page was fairly empty when it first loaded.   Adding a ‘step’ allowed me to specify what packages I wanted to grab for the deployment. This part requires a NuGet package feed to be set up, which is where Deployment Manager will look for the packages. At Red Gate, we already have one set up, so I just needed to tell Deployment Manager about it. Don’t worry; there is a nice guide included on how to go about doing all of this on the ‘Package Feeds’ page in ‘Settings’, if you need any help with setting these bits up.    At Red Gate we use a build server, TeamCity, which is capable of publishing built projects to the NuGet feed we use. This makes the workflow for Format SQL relatively simple: when I commit a change to the project, the build server is configured to grab those changes, build the project, and spit out a new NuGet package to the Red Gate NuGet package feed. My ‘package step’, therefore, is set up to look for this package on our feed. The final part of package step was simply specifying which machines from what environments I wanted to be able to deploy the project to.     Format SQL Now the main Dashboard showed my new project and environment in a rather empty looking grid. Clicking on my project presented me with a nice little message telling me that I am now ready to create my first release!   Create a release Next I clicked on the ‘Create release’ button in the Projects tab. If your feeds and package step(s) were set up correctly, then Deployment Manager will automatically grab the latest version of the NuGet package that you want to deploy. As you can see here, it was able to pick up the latest build for Format SQL and all I needed to do was enter a version number and description of the release.   As you can see underneath ‘Version number’, it keeps track of what version the previous release was given. Clicking ‘Create’ created the release and redirected me to a summary of it where I could check the details before deploying.   I clicked ‘Deploy this release’ and chose the environment I wanted to deploy to and…that’s it. Deployment Manager went off and deployed it for me.   Once I clicked ‘Deploy release’, Deployment Manager started to automatically update and provide continuing feedback about the process. If any errors do arise, then I can expand the results to see where it went wrong. That’s it, I’m done! Keep in mind, if you hit errors with the deployment itself then it is possible to view the log output to try and determine where these occurred. You can keep expanding the logs to narrow down the problem. The screenshot below is not from my Format SQL deployment, but I thought I’d post one to demonstrate the logging output available. Features One of the best bits of Deployment Manager for me is the ability to very, very easily deploy the same release to multiple machines. Deploying this same release to production was just a case of selecting the deployment and choosing the ‘live’ environment as the place to deploy to. Following on from this is the fact that, as Deployment Manager keeps track of all of your releases, it is extremely easy to roll back to a previous release if anything goes pear-shaped! You can view all your previous releases and select one to re-deploy. I needed this feature more than once when differences in my production and staging machines lead to some odd behavior.     Another option is to use the TeamCity integration available. This enables you to set Deployment Manager up so that it will automatically create releases and deploy these to an environment directly from TeamCity, meaning that you can always see the latest version up and running without having to do anything. Machine Specific Deployments ‘What about custom configuration files?’ I hear you shout. Certainly, it was one of my concerns. Our setup on the staging machine is not in line with that on production. What this means is that, should we deploy the same configuration to both, one of them is going to break. Thankfully, it turns out that Deployment Manager can deal with this. Given I had environments ‘staging’ and ‘live’, and that staging used the project’s web.config file, while production (‘live’) required the config file to undergo some transformations, I simply added a web.live.config file in the project, so that it would be included as part of the NuGet package. In this file, I wrote the XML document transformations I needed and Deployment Manager took care of the rest. Another option is to set up ‘variables’ for your project, which allow you to specify key-value pairs for your configuration file, and which environment to apply them to. You’ll find Variables as a full left-hand submenu within the ‘Projects’ tab. These features will definitely be of interest if you have a large number of environments! There are still many other features that I didn’t get a chance to play around with like running PowerShell scripts for more personalised deployments. Maybe next time! Also, let’s not forget that my use case in this article is a very simple one – deploying a single package. I don’t believe that all projects will be equally as simple, but I already appreciate how much easier Deployment Manager could make my life. I look forward to the possibility of moving our other sites over to Deployment Manager in the near future.   Conclusion In this article I have described the steps involved in setting up and configuring an instance of Deployment Manager, creating a new automated deployment process, and using this to actually carry out a deployment. I’ve tried to mention some of the features I found particularly useful, such as error logging, easy release management allowing you to deploy the same release multiple times, and configuration file transformations. If I had to point out one issue, then it would be that the releases are immutable, which from a development point of view makes sense. However, this causes confusion where I have to create a new release to deploy to a newly set up environment – I cannot simply deploy an old release onto a new environment, the whole release needs to be recreated. I really liked how easy it was to get going with the product. Setting up Format SQL and making a first deployment took very little time. Especially when you compare it to how long it takes me to manually deploy the other site, as I described earlier. I liked how it let me know what I needed to do next, with little messages flagging up that I needed to ‘create environments’ or ‘add some deployment steps’ before I could continue. I found the dashboard incredibly convenient. As the number of projects and environments increase, it might become awkward to try and search them and find out what state they are in. Instead, the dashboard handily keeps track of the latest deployments of each project and lets you know what version is running on each of the environments, and when that deployment occurred. Finally, do you remember my complaint about having to rename folders so that I could keep track of what build they came from? This is yet another thing that Deployment Manager takes care of for you. Each release is put into its own directory, which takes the name of whatever version number that release has, though these can be customised if necessary. If you’d like to take a look at Deployment Manager for yourself, then you can download it here.

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