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  • Can I use Linq-to-xml to persist my object state without having to use/know Xpath & XSD Syntax?

    - by Greg
    Hi, Can I use Linq-to-xml to persist my object state without having to use/know Xpath & XSD Syntax? ie. really looking for simple but flexible way to persist a graph of object data (e.g. have say 2 or 3 classes with associations) - if Linq-to-xml were as simple as saying "persist this graph to XML", and then you could also query it via Linq, or load it into memory again/change/then re-save to the xml file.

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  • How can I do this Aggrigate, group by, in query in LINQ?

    - by Ólafur Waage
    Please do not give me a full working example, I want to know how this is done rather than to get some code I can copy paste This is the query I need, and can't for the life of me create it in LINQ. SELECT * FROM dbo.Schedules s, dbo.Videos v WHERE s.VideoID = v.ID AND s.ID IN ( SELECT MAX(ID) FROM dbo.Schedules WHERE ChannelID = 1 GROUP BY VideoID ) ORDER BY v.Rating DESC, s.StartTime DESC I have the "IN" query in LINQ I think, it's something like this var uniqueList = from schedule in db.Schedules where schedule.ChannelID == channelID group schedule by schedule.VideoID into s select new { id = s.Max(i => i.ID) }; It is possibly wrong, but now I can not check in another query for this in a where clause uniqueList.Contains(schedule.ID) There is possibly a better way to write this query, if you have any idea I would love some hints. I get this error and it's not making much sense. The type arguments for method 'System.Linq.Queryable.Contains(System.Linq.IQueryable, TSource)' cannot be inferred from the usage. Try specifying the type arguments explicitly.

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  • What guarantees are there on the run-time complexity (Big-O) of LINQ methods?

    - by tzaman
    I've recently started using LINQ quite a bit, and I haven't really seen any mention of run-time complexity for any of the LINQ methods. Obviously, there are many factors at play here, so let's restrict the discussion to the plain IEnumerable LINQ-to-Objects provider. Further, let's assume that any Func passed in as a selector / mutator / etc. is a cheap O(1) operation. It seems obvious that all the single-pass operations (Select, Where, Count, Take/Skip, Any/All, etc.) will be O(n), since they only need to walk the sequence once; although even this is subject to laziness. Things are murkier for the more complex operations; the set-like operators (Union, Distinct, Except, etc.) work using GetHashCode by default (afaik), so it seems reasonable to assume they're using a hash-table internally, making these operations O(n) as well, in general. What about the versions that use an IEqualityComparer? OrderBy would need a sort, so most likely we're looking at O(n log n). What if it's already sorted? How about if I say OrderBy().ThenBy() and provide the same key to both? I could see GroupBy (and Join) using either sorting, or hashing. Which is it? Contains would be O(n) on a List, but O(1) on a HashSet - does LINQ check the underlying container to see if it can speed things up? And the real question - so far, I've been taking it on faith that the operations are performant. However, can I bank on that? STL containers, for example, clearly specify the complexity of every operation. Are there any similar guarantees on LINQ performance in the .NET library specification?

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  • Performance of Cluster Shared Volume file copy from SAN

    - by Sequenzia
    I am hoping someone can help me out with a strange issue. We are running a Microsoft Failover Cluster with Server 2008 R2 and an Equallogic PS4000 SAN. Our main configuration has 2 Dell Poweredge T710 Servers in the cluster. We have CSV and Quorm setup. The servers each have 10 Broadcom 1Gb NICs. Right now 4 of the NICS are on the iSCSI network for accessing the SAN. They use MPIO and the Dell HIT pack. We have 5 VMs running on each node and everything runs smooth. No noticeable performance issues or anything. From the SAN I can see the 4 iSCSI connections from each server to each volume (CSV and Quorm). Again, it seems to perform great. The problem I am running into is with backups. I have tried a few backup programs like backupchain and Veeam. The problem is both of them are very very slow to backup the VMs. For instance I have a 500GB (fixed disc) VHD that’s running on the cluster. It takes over 18 hours to backup that VHD and that’s with compression and depuping turned off which is supposed to be the fasted. We also have a separate server that is just for backups. It has a lot of directed attached storage. As part of the troubleshooting I decided to bring that server into the cluster as a node. It now has access to the CSV and can read from C:\clusterstorage\volume1 which is where our VHDs live. This backup server only has 2 NICs. 1 NIC is going to the iSCSI network and the other is just on the main network. It has Intel NICS in it without any sort of MPIO or teaming. So with the 3rd server now in the cluster I started doing some benchmarking. I have a test VHD that’s about 7GBs that’s stored in the CSV. I have tested file copying that VHD from all 3 servers to directed attached storage in the respective server. The 2 Dell servers that are the main nodes in the cluster (they house the VMs) are reading that file at about 20Mbs/Sec. Which at that rate is way to slow for the backups. The other server which only has 1 NIC to the SAN is reading at around 100Mbs/Sec. I spent a few hours on the phone with Dell today about this . We went through all kind of tests and he was pretty dumb founded. He really has no idea why that server with only 1 NIC is reading about 5 times as fast as the servers with 4 NICS and MPIO. We looked at the network utilization of the NICs while the file copy was going on. The servers with the 4 NICs had a small increase of activity during the file copy but they only went up to around 8-10% on all 4 NICs. The other server with the 1 NIC jumped up to over 80% during the file copy. I plan on doing some more testing after hours and calling Dell back tomorrow but I really am confused (and so is Dell’s support rep) why I cannot get faster file copy access to the CSV on those servers. Anyone have any input on this? Any feedback would be greatly appreciated. Thanks in advance.

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  • How do I export a large table into 50 smaller csv files of 100,000 records each

    - by Eddie
    I am trying to export one field from a very large table - containing 5,000,000 records, for example - into a csv list - but not all together, rather, 100,000 records into each .csv file created - without duplication. How can I do this, please? I tried SELECT field_name FROM table_name WHERE certain_conditions_are_met INTO OUTFILE /tmp/name_of_export_file_for_first_100000_records.csv LINES TERMINATED BY '\n' LIMIT 0 , 100000 that gives the first 100000 records, but nothing I do has the other 4,900,000 records exported into 49 other files - and how do I specify the other 49 filenames? for example, I tried the following, but the SQL syntax is wrong: SELECT field_name FROM table_name WHERE certain_conditions_are_met INTO OUTFILE /home/user/Eddie/name_of_export_file_for_first_100000_records.csv LINES TERMINATED BY '\n' LIMIT 0 , 100000 INTO OUTFILE /home/user/Eddie/name_of_export_file_for_second_100000_records.csv LINES TERMINATED BY '\n' LIMIT 100001 , 200000 and that did not create the second file... what am I doing wrong, please, and is there a better way to do this? Should the LIMIT 0 , 100000 be put Before the first INTO OUTFILE statement, and then repeat the entire command from SELECT for the second 100,000 records, etc? Thanks for any help. Eddie

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  • LINQ to Twitter v2.1.09 Released

    - by Joe Mayo
    Originally posted on: http://geekswithblogs.net/WinAZ/archive/2013/10/15/linq-to-twitter-v2.1.09-released.aspxToday, I released LINQ to Twitter v2.1.09. Here are important new changes. Bug Fixes This is primarily a bug fix release. Most notably, there were authentication problems in WinRT apps. This is now fixed. New Features One new feature is the addition of ApplicationOnlyAuthentication for WinRT. It is fully async.  Here’s how it works: var auth = new WinRtApplicationOnlyAuthorizer { Credentials = new InMemoryCredentials { ConsumerKey = "", ConsumerSecret = "" } }; if (auth == null || !auth.IsAuthorized) { await auth.AuthorizeAsync(); } var twitterCtx = new TwitterContext(auth); (from search in twitterCtx.Search where search.Type == SearchType.Search && search.Query == SearchTextBox.Text select search) .MaterializedAsyncCallback( async response => await Dispatcher.RunAsync( CoreDispatcherPriority.Normal, async () => { Search searchResponse = response.State.Single(); string message = string.Format( "Search returned {0} statuses", searchResponse.Statuses.Count); await new MessageDialog(message, "Search Complete").ShowAsync(); })); It’s called the WinRtApplicationOnlyAuthorizer. You only need two tokens, ConsumerKey and ConsumerSecret, which come from your Twitter API application settings page. Note: You need a Twitter Application, which you can create at https://dev.twitter.com/. The MaterializedAsyncCallback materializes your query and handles the response. I put everything together in a lambda for demonstration purposes, but you can always replace the callback with a handler of type Action<TwitterAsyncResponse<IEnumerable<T>>>, where T is Search for this example. On the Horizon The next version of LINQ to Twitter is in development. I discussed it at LINQ to Twitter Async. This isn’t complete, but you can download the source code at the LINQ to Twitter site on CodePlex. I’ve competed all the spikes for what I thought would be the hard parts and now have prototypes of queries and commands working. This would be a good time to provide feedback if there are features in the current version that you think could be improved. The current driving forces for the next version will be async and PCL.   @JoeMayo

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  • Importing csv list of contacts into Exchange 2007 GAL and create Distribution Group

    - by Ken Ray
    Here's the situation: We have a list of about 1,000 contacts (Lawyers in the area our court serves) with name and email address. I've been asked to create an email distribution list that can be used to sent emails to all of the external users on that list. I've seen various articles using the Exchange Management Shell and the Import-csv command piped through a ForEach-Object to a New-MailContact to set up the contacts. However, Exchange Management Shell is rather unhelpful, and it isn't working. What I believe I need to do is: 1) Set up a new distribution group using the Exchange Management Console. Let's say this new distribution group (which appears in the list of Distribution Groups under Recipient Configuration) is called "FloridaBar". 2) Make sure I have a csv file of the information I want to import. 3) Open Exchange Management Shell, and enter the following command: Import-csv C:\filename.csv | ForEach-Object { New-MailContact -Name $."NameColumnName" -ExternalEmailAddress $."EmailAddressColumn" -org FloridaBar Now, creating 1,000+ contacts in active directory - I assume that shouldn't be an issue. Do I have the "-org" parm wrong? Do I need to spell out the complete organization unit name (my.domain.name/Users/FloridaBar)? Is there a better way of doing this? Thanks in advance Ken

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  • linux + create host file from CSV file by sed or awk or perl

    - by yael
    I have the following CSV file this file defined which Linux machine exist in the system and there ip's my target is to create host file from this file please advice how to create host file as example 1 from my CSV file ( I need to match the IP address from CSV file and put it on the first field of the host file , then match the LINUX name and locate this name in the sec field – as example 1 ) remark - should be performed by sed or awk or perl .. , I need to write the solution in my bash script CSV file , machine , VM-LINUX1 , SZ , Phy , 10.213.158.18 , PROXY , VM-LINUX2 , SZ , 10.213.158.19 , OLD HW , VM-LINUX3 , SZ , 10.213.158.20 , , VM-LINUX4 , SZ , Phy , 10.213.158.21 , , VM-LINUX5 , SZ , Phy , OUT , EXT , LAN3 , 10.213.158.22 , INTERNAL , VM-LINUX6 , SZ , Phy , 10.213.158.23 , , server , new HW , VM-LINUX7 , SZ , Phy , 10.213.158.24 , OUT, LAN3 , VM-LINUX8 , SZ , 10.213.158.25 , OLD HW , machine , VM-LINUX9 , SZ , Phy , INT , 10.213.158.26 , LAN2, AN45, , VM-LINUX10 , SZ , Phy , 10.213.158.27 , , VM-LINUX11 , SZ , Phy , LAN5 , 10.213.158.28 , example 1 ( host file ) 10.213.158.18 VM-LINUX1 10.213.158.19 VM-LINUX2 10.213.158.20 VM-LINUX3 10.213.158.21 VM-LINUX4 10.213.158.22 VM-LINUX5 10.213.158.23 VM-LINUX6 10.213.158.24 VM-LINUX7 10.213.158.25 VM-LINUX8 10.213.158.26 VM-LINUX9 10.213.158.27 VM-LINUX10 10.213.158.25 VM-MACHINE8 10.213.158.26 STAR9 10.213.158.27 TOP10 10.213.158.28 SERVER11

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  • excel truncating phone number

    - by user15586
    I have a csv file that contains cells such as "+1.8882789780". When viewed in Excel, it loses the last digit possibly due to excel truncation. Is there a way to either change the setting in Excel to prevent this from happening or change the csv file in some way? One way is to wrap single quotes around the cell contents in addition to the double quotes. "'+1.8882789780'" Is there a better way?

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  • Excel removing leading leading zeros when displaying CSV data

    - by Velika Kudac
    I have a CSV text file with the following content: "Col1","Col2" "01",A "2",B "10", C When I open it up with Excel, it displays as shown here: Note that Cell 2A attempts to display "01" as a number without a leading 0. When I format rows 2 through 4 as "Text", it changes the display to ...but still the leading "0" is gone. Is there a way to open up a CSV file in XLS and be able to see all of the leading zeros in the file by flipping some option? I do not want to have to retype '01 in every cell that should have a leading zero. Furthermore, using a leading apostrophe necessitates that the changes be saved to a XLS format when CSV is desired. My goal is simply to use Excel to view the actual content of the file as text without Excel trying to do me any formatting favors.

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  • Cannot view dates of emails(no date field), in my CSV file exported from MS Outlook

    - by barlop
    I am using Outlook 2010 - I have my emails showing in there. and exported my emails, into a csv file. (file..options..advanced...export..export to a file.. I have opened that csv file in excel Here is a list of the fields it shows. I see "Date" doesn't appear among them. Subject Body From: (Name) From: (Address) From: (Type) To: (Name) To: (Address) To: (Type) CC: (Name) CC: (Address) CC: (Type) BCC: (Name) BCC: (Address) BCC: (Type) Billing Information Categories Importance Mileage Sensitivity Any idea why "Date" isn't included, and how to include it? Also, (and less importantly, and as a very secondary issue) is there a convenient way to read the csv file? reading an email with a long body, in excel, is not convenient, I need to select all of the body from the cell and copy/paste it into notepad.

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  • Is there any way of preventing .csv files being converted into excel format

    - by Kevin Trainer
    I'm trying to work with an automated testing tool which can use .csv files as its data sourse. After saving a notepad file containing a number of fields and data seperated by commas as .csv it appears to have been converted to an excel file. When I run the test, only the first line of values is identified and can be run within the automated test. Not sure if this is expected with the testing product (www.badboy.co.au), but just wondered if there was a way of preventing excel from taking control of the .csv file? Any helpfull feedback would be great.

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  • A Trio of Presentations: Little Wonders, StyleCop, and LINQ/Lambdas

    - by James Michael Hare
    This week is a busy week for me.  First of all I’m giving another presentation on a LINQ/Lambda primer for the rest of the developers in my company.  Of Lambdas and LINQ View more presentations from BlackRabbitCoder Then this Saturday the 25th of June I’ll be reprising my Little Wonders presentation for the Kansas City Developers Camp.  If you are in the area I highly recommend attending and seeing the other great presentations as well.  Their link is here. Little Wonders View more presentations from BlackRabbitCoder Finally, this Monday the 27th I’ll be speaking at the Saint Louis .NET Users group, giving my Automating Code Standards Using StyleCop and FxCop presentation.  If you are in the Saint Louis area stop by!  There’s two other simultaneous presentations as well if they’re more suited to your interests.  The link for the SLDNUG is here. Automating C# Coding Standards using StyleCop and FxCop View more presentations from BlackRabbitCoder Tweet Technorati Tags: C#,.NET,LINQ,Lambda,StyleCop,FxCop,Little Wonders

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  • Macro to Add using System.Linq

    - by Aligned
    I have Visual Studio 2010 setup to remove and sort settings on save with the Power Commands extensions. This is great, but sometimes it removes the using System.Linq at the top. I also find myself scrolling to the top to add the using when I first add System.Linq. So I wrote a quick macro to do it for me. Sub AddUsingLinq()        DTE.ActiveDocument.Selection.StartOfDocument()        DTE.ActiveDocument.Selection.StartOfLine(vsStartOfLineOptions.vsStartOfLineOptionsFirstText)        DTE.ActiveDocument.Selection.Text = "using System.Linq;"        DTE.ActiveDocument.Selection.NewLine()        DTE.ExecuteCommand("Edit.FormatDocument")        DTE.ExecuteCommand("Edit.RemoveAndSort")        DTE.ActiveDocument.Save() DTE.ExecuteCommand("View.NavigateBackward")    End SubHook this up to a shortcut (tools -> options -> keyboard, I chose ctrl + x, c) and you'll be moving faster than ever.

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  • Entity Framework 4.0: Optimal and horrible SQL

    - by DigiMortal
    Lately I had Entity Framework 4.0 session where I introduced new features of Entity Framework. During session I found out with audience how Entity Framework 4.0 can generate optimized SQL. After session I also showed guys one horrible example about how awful SQL can be generated by Entity Framework. In this posting I will cover both examples. Optimal SQL Before going to code take a look at following model. There is class called Event and I will use this class in my query. Here is the LINQ To Entities query that uses small anonymous type. var query = from e in _context.Events             select new { Id = e.Id, Title = e.Title }; Debug.WriteLine(((ObjectQuery)query).ToTraceString()); Running this code gives us the following SQL. SELECT      [Extent1].[event_id] AS [event_id],      [Extent1].[title] AS [title]  FROM [dbo].[events] AS [Extent1] This is really small – no additional fields in SELECT clause. Nice, isn’t it? Horrible SQL Ayende Rahien blog shows us darker side of Entiry Framework 4.0 queries. You can find comparison betwenn NHibernate, LINQ To SQL and LINQ To Entities from posting What happens behind the scenes: NHibernate, Linq to SQL, Entity Framework scenario analysis. In this posting I will show you the resulting query and let you think how much better it can be done. Well, it is not something we want to see running in our servers. I hope that EF team improves generated SQL to acceptable level before Visual Studio 2010 is released. There is also morale of this example: you should always check out the queries that O/R-mapper generates. Behind the curtains it may silently generate queries that perform badly and in this case you need to optimize you data querying strategy. Conclusion Entity Framework 4.0 is new product with a lot of new features and it is clear that not everything is 100% super in its first release. But it still great step forward and I hope that on 12.04.2010 we have new promising O/R-mapper available to use in our projects. If you want to read more about Entity Framework 4.0 and Visual Studio 2010 then please feel free to follow this link to list of my Visual Studio 2010 and .NET Framework 4.0 postings.

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  • Getting the first result from a LINQ query - why does ElementAt<T>(0) fails when First<T>() succeeds

    - by Mr Roys
    I have a method AddStudent() which looks for a student with the same name and returns an existing student from the database if there is a student with the same name, otherwise it creates a new student and adds it to the database. I'm curious why se = students.First<StudentEntity>(); succeeds when se = students.ElementAt<StudentEntity>(0); fails when I try to get the first result from the LINQ query. Aren't the two methods the same? The full code for the method is shown below. public Student AddStudent(string name) { using (SchoolEntities db = new SchoolEntities()) { // find student with same name via LINQ var students = from s in db.StudentEntitySet where s.name == name select s; StudentEntity se = default(StudentEntity); // if student with the same name is already present, return // that student if (students.Count<StudentEntity>() > 0) { // if i use ElementAt, if fails with a "LINQ to Entities does not // recognize the method 'StudentEntity ElementAt[StudentEntity] // (System.Linq.IQueryable`1[StudentEntity], Int32)' method, // and this method cannot be translated into a store expression.", // but not when I use First. Why? // se = students.ElementAt<StudentEntity>(0); se = students.First<StudentEntity>(); } else { // passing 0 for first parameter (id) since it's represented by // a BigInt IDENTITY field in the database so any value // doesn't matter. se = StudentEntity.CreateStudentEntity(0, name); db.AddToStudentEntitySet(se); db.SaveChanges(); } // create a Student object from the Entity object return new Student(se); } } Thanks!

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  • 'LINQ query plan' horribly inefficient but 'Query Analyser query plan' is perfect for same SQL!

    - by Simon_Weaver
    I have a LINQ to SQL query that generates the following SQL : exec sp_executesql N'SELECT COUNT(*) AS [value] FROM [dbo].[SessionVisit] AS [t0] WHERE ([t0].[VisitedStore] = @p0) AND (NOT ([t0].[Bot] = 1)) AND ([t0].[SessionDate] > @p1)',N'@p0 int,@p1 datetime', @p0=1,@p1='2010-02-15 01:24:00' (This is the actual SQL taken from SQL Profiler on SQL Server 2008.) The query plan generated when I run this SQL from within Query Analyser is perfect. It uses an index containing VisitedStore, Bot, SessionDate. The query returns instantly. However when I run this from C# (with LINQ) a different query plan is used that is so inefficient it doesn't even return in 60 seconds. This query plan is trying to do a key lookup on the clustered primary key which contains a couple million rows. It has no chance of returning. What I just can't understand though is that the EXACT same SQL is being run - either from within LINQ or from within Query Analyser yet the query plan is different. I've ran the two queries many many times and they're now running in isolation from any other queries. The date is DateTime.Now.AddDays(-7), but I've even hardcoded that date to eliminate caching problems. Is there anything i can change in LINQ to SQL to affect the query plan or try to debug this further? I'm very very confused!

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  • How to use different providers for Linq to entities?

    - by Anders Svensson
    I'm trying to familiarize myself a bit more with database programming, and I'm looking at different ways of creating a data access layer for applications. I've tried out a few ways but there is such a jungle of different database technologies that I don't know what to learn. For instance I've tried using datasets with tableadapters. Using that I am able to switch data provider rather easily (by programming against the interfaces such as IDbConnection). This is one thing I would want to achieve. But I also know everyone's talking about LINQ, and I'm trying to get to know that a bit better too. So I have tried using Linq to Sql classes as the data access layer as well, but apparently this is not provider independent (works only for SQL Server). So then I read about the Entity Framework (which just as Linq to SQL apparently has gotten its share of bashing already...). It's supposed to be provider independent everybody says, but how? I tried out a tutorial to create an entity data model, but the only providers to choose from were SQL Server/Express. Just for learning purposes, I would like to know how to use the entity framework with MS Access/OleDb. Also, I would appreciate some input on what is the preferred database technology for data access. Is it LINQ still after all the bashing, or should you just use datasets because they are provider independent? Any pointers for what to learn would be great, because it's just too much to learn it all if I'm not going to use it in the end...!

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  • Defaults for Exporting Data in Oracle SQL Developer

    - by thatjeffsmith
    I was testing a reported bug in SQL Developer today – so the bug I was looking for wasn’t there (YES!) but I found a different one (NO!) – and I was getting frustrated by having to check the same boxes over and over again. What I wanted was INSERT STATEMENTS to the CLIPBOARD. Not what I want! I’m always doing the same thing, over and over again. And I never go to FILE – that’s too permanent for my type of work. I either want stuff to the clipboard or to the worksheet. Surely there’s a way to tell SQL Developer how to behave? Oh yeah, check the preferences So you can set the defaults for this dialog. Go to: Tools – Preferences – Database – Utilities – Export Now I will always start with ‘INSERT’ and ‘Clipboard’ – woohoo! Now, I can also go INTO the preferences for each of the different formats to save me a few more clicks. I prefer pointy hats (^) for my delimiters, don’t you? So, spend a few minutes and set each of these to what you’re normally doing and save yourself a bunch of time going forward.

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  • Limit of 88 bytes on response.write?

    - by Chris
    I am trying to serve a csv file from a wcf service, as a string response. It looks like this: HttpContext.Current.Response.AddHeader("Content-disposition", "attachment; filename=ImportErrors.csv"); HttpContext.Current.Response.ContentType = "text/csv"; HttpContext.Current.Response.Write(myCsvContent); The response StatusCode is set to (int)HttpStatusCode.OK (200) It works, but I am only getting 88 bytes of my csv and the rest is cut off (not shown). Any suggestions on where to look? I don't see any custom entries in my web.config that are setting a limit.

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  • Why will this for loop not return one field from list rather than the list?

    - by Dick Eshelman
    import csv """sample row = 10/6/2010,73.42,74.43,72.9,74.15,2993500""" filename_in = 'c:/python27/scripts/fiverows.csv' reader = csv.reader(open(filename_in, "rb"), dialect="excel", delimiter="\t", quoting =csv.QUOTE_MINIMAL) for row in reader: for item in row: print 'row = ',row print 'item = ', item When you run this script and print the row you get the sample row returned in [] as a list. When you print the item you get the sample row as an unquoted string. Why do I not get each field ie, (10/6/2010), (73.42), etc. returned as an item? How do I return a single item?

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  • How to get the number of columns from a JDBC Resultset?

    - by Sanoj
    I am using CsvJdbc (it is a JDBC-driver for csv-files) to access a csv-file. I don't know how many columns the csv-file contains. How can I get the number of columns? Is there any JDBC-function for this? I can not find any methods for this in java.sql.Resultset. For acessing the file, I use code similar to the example on the CsvJdbc website.

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  • Python/Numpy - Save Array with Column AND Row Titles

    - by Scott B
    I want to save a 2D array to a CSV file with row and column "header" information (like a table). I know that I could use the header argument to numpy.savetxt to save the column names, but is there any easy way to also include some other array (or list) as the first column of data (like row titles)? Below is an example of how I currently do it. Is there a better way to include those row titles, perhaps some trick with savetxt I'm unaware of? import csv import numpy as np data = np.arange(12).reshape(3,4) # Add a '' for the first column because the row titles go there... cols = ['', 'col1', 'col2', 'col3', 'col4'] rows = ['row1', 'row2', 'row3'] with open('test.csv', 'wb') as f: writer = csv.writer(f) writer.writerow(cols) for row_title, data_row in zip(rows, data): writer.writerow([row_title] + data_row.tolist())

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  • Allow users to pull temporary data then delete table?

    - by JM4
    I don't know the best way to title this question but am trying to accomplish the following goal: When a client logs into their profile, they are presented with a link to download data from an existing database in CSV format. The process works, however, I would like for this data to be 'fresh' each time they click the link so my plan was - once a user has clicked the link and downloaded the CSV file, the database table would 'erase' all of its data and start fresh (be empty) until the next set of data populated it. My EXISTING CSV creation code: <?php $host = 'localhost'; $user = 'username'; $pass = 'password'; $db = 'database'; $table = 'tablename'; $file = 'export'; $link = mysql_connect($host, $user, $pass) or die("Can not connect." . mysql_error()); mysql_select_db($db) or die("Can not connect."); $result = mysql_query("SHOW COLUMNS FROM ".$table.""); $i = 0; if (mysql_num_rows($result) > 0) { while ($row = mysql_fetch_assoc($result)) { $csv_output .= $row['Field'].", "; $i++; } } $csv_output .= "\n"; $values = mysql_query("SELECT * FROM ".$table.""); while ($rowr = mysql_fetch_row($values)) { for ($j=0;$j<$i;$j++) { $csv_output .= '"'.$rowr[$j].'",'; } $csv_output .= "\n"; } $filename = $file."_".date("Y-m-d",time()); header("Content-type: application/vnd.ms-excel"); header("Content-disposition: csv" . date("Y-m-d") . ".csv"); header( "Content-disposition: filename=".$filename.".csv"); print $csv_output; exit; ?> any ideas?

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