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  • is PHP itself transforming into a framework?

    - by Elzo Valugi
    At the beginning PHP was a scripting language. But after the introduction and improvement of OOP I see more and more objects added to the core. They started with SPL which grew a lot, now we have DOMDocument family, DateTime family which should be part of PECL, Pear or Zend Framework or implemented by each one of us. Shouldn't be php only for build-in functions and all these objects passed to something else? Example. DateTime class is part of the core and I see it very similar with Zend_Date.

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  • PC is randomly shutting off

    - by Bobby
    I have a PC which is randomly shutting off (the hard way, like someone pulled the plug). It's no heat problem, because this can happen after 2 minutes of operation or after 4 hours and I checked the temperature. It's also no problem of the operation system, because it will also do that while in BIOS. If it happens once, you can be sure that it will happen within the next hour another two or three times, and then it works again for over a week or even longer. Possible causes I've thought about so far are: Voltage Fluctuation Loose contact (already replugged all cables within the PC, no luck) Faulty PSU Maybe someone has more ideas to this? P.s.: I don't have the hardware specs with me right now, I'll post them as soon as I get them.

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  • How to declare string to be equal on textbox.text after that

    - by Nikola Obretenov
    where is the mistake here: static int count = 0; string s; private void SetClock_Click(object sender, EventArgs e) { txtSend.Text = s; count++; label5.Text = count.ToString("X2"); DateTime time = DateTime.Now; s = "4D-" + "1A-" + "2B-" + "3C-" + (label5.Text.ToString()); } on first click i get a click value 01, but dont get the txtsend.text ... on second click i get value 02 but in txtsend.text i get the 4D-1A-2B-3C-01

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  • Oracle Logical Standby redo generation

    - by DCookie
    Oracle 10.2.0.4 database with a logical standby on Win2K3. Recently a rather large delete operation was carried out on the production instance. I'm experiencing difficulty with the logical standby, in that it gets a couple of hundred (58M size) archive logs into the operation and the apply process fails with an out-of-memory error. Unfortunately, every time it fails it has to restart the apply from the beginning of the transaction. This is taking a couple of days each time. Anyway, in trying to resolve this problem, I've noticed that each archive log from the production system generates 5 or 6 log switches on the standby. I don't understand why this should be. Anyone have any ideas? A related question that I've not found the answer for: does anyone know if the logical standby must be running in archivelog mode? I really don't have a need to keep the logs.

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  • How much Stored Procedures created everyday ?

    - by Space Cracker
    I make a query that return to me the count of Stored Procedure that created everyday as follow SELECT convert(varchar, crdate, 103) as Date,Count(*) as Counter FROM sysobjects WHERE (xtype = 'p') AND (name NOT LIKE 'dt%') Group by convert(varchar, crdate, 103) and its already work but dates appear in string format that i can't order it such as below 01/03/2010 3 01/04/2008 4 01/05/2010 5 01/11/2008 1 01/12/2008 4 02/03/2008 1 02/03/2010 2 02/04/2008 4 02/05/2010 2 02/11/2008 2 02/11/2009 2 02/12/2008 4 03/01/2010 1 03/02/2010 2 03/03/2010 2 03/04/2008 2 03/04/2010 2 03/05/2008 1 03/05/2010 2 I want to make that in which date is in datetime format that i can make order by successfully, i tried convert(datetime, crdate, 103) but it show Full date any idea of how to do ?

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  • IsAuthenticated is false!

    - by Naor
    This is how I login ('user' holds the data of the user): HttpResponse Response = HttpContext.Current.Response; HttpRequest Request = HttpContext.Current.Request; FormsAuthenticationTicket ticket = new FormsAuthenticationTicket(1, user.UserId.ToString(), DateTime.Now, DateTime.Now.AddHours(12), false, UserResolver.Serialize(user)); HttpCookie cookie = new HttpCookie(FormsAuthentication.FormsCookieName, FormsAuthentication.Encrypt(ticket)); cookie.Path = FormsAuthentication.FormsCookiePath; Response.Cookies.Add(cookie); string redirectUrl = user.HomePage; Response.Redirect(redirectUrl); After this login I get IsAuthenticated == false. Why?? It worked for me before an hour but I don't know what is wrong now.

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  • SQL error C# - Parameter already defined

    - by jakesankey
    Hey there. I have a c# application that parses txt files and imports the data from them into a sql db. I was using sqlite and am now working on porting it to sql server. It was working fine with sqlite but now with sql i am getting an error when it is processing the files. It added the first row of data to the db and then says "parameter @PartNumber has already been declared. Variable names must be unique within a batch or stored procedure". Here is my whole code and SQL table layout ... the error comes at the last insertCommand.ExecuteNonQuery() instance at the end of the code... SQL TABLE: CREATE TABLE Import ( RowId int PRIMARY KEY IDENTITY, PartNumber text, CMMNumber text, Date text, FeatType text, FeatName text, Value text, Actual text, Nominal text, Dev text, TolMin text, TolPlus text, OutOfTol text, FileName text ); CODE: using System; using System.Data; using System.Data.SQLite; using System.IO; using System.Text.RegularExpressions; using System.Threading; using System.Collections.Generic; using System.Linq; using System.Data.SqlClient; namespace JohnDeereCMMDataParser { internal class Program { public static List<string> GetImportedFileList() { List<string> ImportedFiles = new List<string>(); using (SqlConnection connect = new SqlConnection(@"Server=FRXSQLDEV;Database=RX_CMMData;Integrated Security=YES")) { connect.Open(); using (SqlCommand fmd = connect.CreateCommand()) { fmd.CommandText = @"IF (EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = 'RX_CMMData' AND TABLE_NAME = 'Import')) BEGIN SELECT DISTINCT FileName FROM Import; END"; fmd.CommandType = CommandType.Text; SqlDataReader r = fmd.ExecuteReader(); while (r.Read()) { ImportedFiles.Add(Convert.ToString(r["FileName"])); } } } return ImportedFiles; } private static void Main(string[] args) { Console.Title = "John Deere CMM Data Parser"; Console.WriteLine("Preparing CMM Data Parser... done"); Console.WriteLine("Scanning for new CMM data... done"); Console.ForegroundColor = ConsoleColor.Gray; using (SqlConnection con = new SqlConnection(@"Server=FRXSQLDEV;Database=RX_CMMData;Integrated Security=YES")) { con.Open(); using (SqlCommand insertCommand = con.CreateCommand()) { SqlCommand cmdd = con.CreateCommand(); string[] files = Directory.GetFiles(@"C:\Documents and Settings\js91162\Desktop\", "R303717*.txt*", SearchOption.AllDirectories); List<string> ImportedFiles = GetImportedFileList(); foreach (string file in files.Except(ImportedFiles)) { string FileNameExt1 = Path.GetFileName(file); cmdd.CommandText = @" IF (EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = 'RX_CMMData' AND TABLE_NAME = 'Import')) BEGIN SELECT COUNT(*) FROM Import WHERE FileName = @FileExt; END"; cmdd.Parameters.Add(new SqlParameter("@FileExt", FileNameExt1)); int count = Convert.ToInt32(cmdd.ExecuteScalar()); con.Close(); con.Open(); if (count == 0) { Console.WriteLine("Parsing CMM data for SQL database... Please wait."); insertCommand.CommandText = @" INSERT INTO Import (FeatType, FeatName, Value, Actual, Nominal, Dev, TolMin, TolPlus, OutOfTol, PartNumber, CMMNumber, Date, FileName) VALUES (@FeatType, @FeatName, @Value, @Actual, @Nominal, @Dev, @TolMin, @TolPlus, @OutOfTol, @PartNumber, @CMMNumber, @Date, @FileName);"; insertCommand.Parameters.Add(new SqlParameter("@FeatType", DbType.Decimal)); insertCommand.Parameters.Add(new SqlParameter("@FeatName", DbType.Decimal)); insertCommand.Parameters.Add(new SqlParameter("@Value", DbType.Decimal)); insertCommand.Parameters.Add(new SqlParameter("@Actual", DbType.Decimal)); insertCommand.Parameters.Add(new SqlParameter("@Nominal", DbType.Decimal)); insertCommand.Parameters.Add(new SqlParameter("@Dev", DbType.Decimal)); insertCommand.Parameters.Add(new SqlParameter("@TolMin", DbType.Decimal)); insertCommand.Parameters.Add(new SqlParameter("@TolPlus", DbType.Decimal)); insertCommand.Parameters.Add(new SqlParameter("@OutOfTol", DbType.Decimal)); string FileNameExt = Path.GetFullPath(file); string RNumber = Path.GetFileNameWithoutExtension(file); string RNumberE = RNumber.Split('_')[0]; string RNumberD = RNumber.Split('_')[1]; string RNumberDate = RNumber.Split('_')[2]; DateTime dateTime = DateTime.ParseExact(RNumberDate, "yyyyMMdd", Thread.CurrentThread.CurrentCulture); string cmmDate = dateTime.ToString("dd-MMM-yyyy"); string[] lines = File.ReadAllLines(file); bool parse = false; foreach (string tmpLine in lines) { string line = tmpLine.Trim(); if (!parse && line.StartsWith("Feat. Type,")) { parse = true; continue; } if (!parse || string.IsNullOrEmpty(line)) { continue; } Console.WriteLine(tmpLine); foreach (SqlParameter parameter in insertCommand.Parameters) { parameter.Value = null; } string[] values = line.Split(new[] { ',' }); for (int i = 0; i < values.Length - 1; i++) { SqlParameter param = insertCommand.Parameters[i]; if (param.DbType == DbType.Decimal) { decimal value; param.Value = decimal.TryParse(values[i], out value) ? value : 0; } else { param.Value = values[i]; } } insertCommand.Parameters.Add(new SqlParameter("@PartNumber", RNumberE)); insertCommand.Parameters.Add(new SqlParameter("@CMMNumber", RNumberD)); insertCommand.Parameters.Add(new SqlParameter("@Date", cmmDate)); insertCommand.Parameters.Add(new SqlParameter("@FileName", FileNameExt)); // insertCommand.ExecuteNonQuery(); } } } Console.WriteLine("CMM data successfully imported to SQL database..."); } con.Close(); } } } }

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  • insert into several inheritance tables with OUTPUT - sql servr 2005

    - by csetzkorn
    Hi, I have a bunch of items – for simplicity reasons – a flat table with unique names seeded via bulk insert: create table #items ( ItemName NVARCHAR(255) ) The database has this structure: create table Statements ( Id INT IDENTITY NOT NULL, Version INT not null, FurtherDetails varchar(max) null, ProposalDateTime DATETIME null, UpdateDateTime DATETIME null, ProposerFk INT null, UpdaterFk INT null, primary key (Id) ) create table Item ( StatementFk INT not null, ItemName NVARCHAR(255) null, primary key (StatementFk) ) Here Item is a child of Statement (inheritance). I would like to insert items in #items using a set based approach (avoiding triggers and loops). Can this be achieved with OUTPUT in my scenario. A ‘loop based’ approach is just too slow where I use something like this: insert into Statements (Version, FurtherDetails, ProposalDateTime, UpdateDateTime, ProposerFk, UpdaterFk) VALUES (1, null, getdate(), getdate(), @user_id, @user_id) etc. This is a start for the OUTPUT based approach – but I am not sure whether this would work in my case as ItemName is only inserted into Item: insert into Statements ( Version, FurtherDetails, ProposalDateTime, UpdateDateTime, ProposerFk, UpdaterFk ) output inserted.Id ... ??? Thanks. Best wishes, Christian

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  • How do i have optional parameter but still validate them in asp.net mvc routing ?

    - by ooo
    I have this route that i just added routes.MapRoute( "MyRoute", "MyController/{action}/{orgId}/{startDate}/{endDate}", new { controller = "MyController", action = "MyAction", orgId = 0, startDate = DateTime.Today.AddMonths(-1), endDate = DateTime.Today }, new { action = new FromValuesListConstraint(new string[] { "MyAction", "MyActionEx" }), orgId = new IntegerRouteConstraint(), startDate = new DateTimeRouteConstraint(), endDate = new DateTimeRouteConstraint() } when i put in this url, it resolves down to the default route (controller, action,id) and the above rout does not catch this url: http://localhost:1713/MyController/MyAction/16 But this below works fine. http://localhost:1713/MyController/MyAction/16/11-May-10/11-May-10 my question is that i thought both would work as i am giving default values to the startDate and enddate fields i tested this using the RouteDebugger and this route turned up false how can i have these last two parameter as optional but still have the validation ?

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  • Linq to NHibernate - How to include parent object and only certain child objects

    - by vakman
    Given a simplified model like the following: public class Enquiry { public virtual DateTime Created { get; set; } public virtual Sender Sender { get; set; } } public class Sender { public virtual IList<Enquiry> Enquiries { get; set; } } How can you construct a Linq to Nhibernate query such that it gives you back a list of senders and their enquiries where the enquiries meet some criteria. I have tried something like this: return session.Linq<Enquiry>() .Where(enquiry => enquiry.Created < DateTime.Now) .Select(enquiry => enquiry.Sender) In this case I get an InvalidCastException saying you can't cast type Sender to type Enquiry. Any pointers on how I can do this without using HQL?

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  • Binning into timeslots - Is there a better way than using list comp?

    - by flyingcrab
    I have a dataset of events (tweets to be specific) that I am trying to bin / discretize. The following code seems to work fine so far (assuming 100 bins): HOUR = timedelta(hours=1) start = datetime.datetime(2009,01,01) z = [dt + x*HOUR for x in xrange(1, 100)] But then, I came across this fateful line at python docs 'This makes possible an idiom for clustering a data series into n-length groups using zip(*[iter(s)]*n)'. The zip idiom does indeed work - but I can't understand how (what is the * operator for instance?). How could I use to make my code prettier? I'm guessing this means I should make a generator / iterable for time that yields the time in graduations of an HOUR?

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  • How do I group a SSRS report by month?

    - by Anthony K
    I have a set of data that includes a field with the datetime that events happen. i want to group the events by month. I haven't come across a simple and elegant expression to achieve this. So far all I can come up with is to convert the field to a date, then take the year and month as integers and then convert this back to a string with the day set to 1. In Crystal Reports I would group on the datetime field and then set the period to month, very easy. I am sure there is an easy answer to this that I haven't been able to find.

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  • Data in column not changed

    - by shanks
    I have sql 2005 and when i run below query, data from RealTimeLog table transfer to History but when new data come in RealTimeLog table old data not changed by new one means OutTime data is not changed with new data from RealTimeLog. insert into History (UserID,UserName,LogDate, [InTime], [OutTime]) SELECT UserID,UserName,[LogDate],CONVERT(nvarchar,MIN(CONVERT(datetime, [LogTime], 108)), 108), CONVERT(nvarchar, MAX(CONVERT(datetime, [LogTime], 108)), 108) From RealTimeLog where not Exists (select * from History H Where H.UserID = RealTimeLog.UserID AND H.UserName=RealTimeLog.UserName AND H.LogDate=RealTimeLog.LogDate) GROUP BY UserID,UserName,[LogDate] ORDER BY UserID,[LogDate] for ex. 1 Shanks 02/05/2010 9:00 10:00 if new Max time generated suppose 11:00 in RealtimeLog then it is not inserted in History table and output remain same as above.

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  • Linq query: append column to query results

    - by jrubengb
    I am trying to figure out how to append a column to Linq query results based on the max value of the query. Essentially, I want to create an EnumerableRowCollection of DataRows that would include a max value record with the same value for each record. So if i have a hundred records returned through the query, I want to next calculate the max value of one of the fields, then append that max value to the original query table: DataTable dt = new DataTable(); dt = myDataSet.myDataTable; EnumerableRowCollection<DataRow> qrySelectRecords = (from d in dt.AsEnumerable() where d.Field<DateTime>("readingDate") >= startDate && g.Field<DateTime>("readingDate") <= endDate select d); Here's where I need help: double maxValue = qrySelectRecords.Field<double>("field1").Max(); foreach (DataRow dr in qrySelectRecords) { qrySelectRecords.Column.Append(maxValue) }

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  • Model Django Poll

    - by MacPython
    I followed the django tutorial here: http://docs.djangoproject.com/en/dev/intro/tutorial01/ and now I am at creating a poll. The code below works fine until I want to create choices, where for some reason I always get this error message: line 22, in unicode return self.question AttributeError: 'Choice' object has no attribute 'question' Unfortunatley, I dont understand where I made an error. Any help would be greatly appreciated. Thanks for the time! CODE: import datetime from django.db import models class Poll(models.Model): question = models.CharField(max_length=200) pub_date = models.DateTimeField('date published') def __unicode__(self): return self.question def was_published_today(self): return self.pub_date.date() == datetime.date.today() class Choice(models.Model): poll = models.ForeignKey(Poll) choice = models.CharField(max_length=200) votes = models.IntegerField() def __unicode__(self): return self.question

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  • i need to use string variable in the Proc in sql server database 2005

    - by bassam
    I have this procedure CREATE Proc [dbo].Salse_Ditail -- Add the parameters for the stored procedure here @Report_Form varchar(1) , @DateFrom datetime , @DateTo datetime , @COMPANYID varchar(3), @All varchar(1) , @All1 varchar(1) , @All2 varchar(1) , @All3 varchar(1) , @All4 varchar(1) , @All5 varchar(1) , @Sector varchar(10), @Report_Parameter nvarchar(max) as BEGIN -- SET NOCOUNT ON added to prevent extra result sets from -- interfering with SELECT statements. DECLARE @STRWhere nvarchar(max) IF @All5=0 AND @All4=0 AND @All3=0 AND @All2=0 AND @All1=0 and @All=1 set @STRWhere= N'and Sector_id = @Sector' if @Report_Form =1 or @Report_Form =3 or @Report_Form =4 SELECT RETURNREASONCODEID, SITE,SITE_NAME,Factory_id,Factory_Name,Sector_id,sector_name,Customer_name, Customer_id,ITEMID,ITEMNAME,SALESMANID,SALESMAN_NAME,Net_Qty,Net_Salse,Gross_Sales,Gross_Qty, NETWEIGHT_Gross,NETWEIGHT_salse_Gross,NETWEIGHT_NET,NETWEIGHT_salse_NET,Return_Sales,Free_Good, CollectionAmount FROM hal_bas_new_rep WHERE DATAAREAID =@COMPANYID AND INVOICEDATE >= @DateFrom AND INVOICEDATE <= @DateTo and Report_Activti = @Report_Form if @Report_Form =2 SELECT RETURNREASONCODEID , RETURNREASONDESC, SITE , SITE_NAME , Factory_id , Factory_Name , Sector_id , sector_name , Customer_name , Customer_id , ITEMID , ITEMNAME , SALESMANID , SALESMAN_NAME , Return_Sales FROM dbo.hal_bas_new_rep WHERE DATAAREAID =@COMPANYID AND INVOICEDATE >= @DateFrom AND INVOICEDATE <= @DateTo and Report_Activti = @Report_Form and RETURNREASONCODEID in ( SELECT Val FROM dbo.fn_String_To_Table(@Report_Parameter,',',1) ) /* @STRWhere // question: how can I use the variable here? */ end GO As you see I'm constructing a condition for the WHERE clause in a variable, but I don't know how to use it.

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  • EntityFramework: Access dabase-column using user defined Type

    - by Nils
    I "inherited" an old Database where dates are stored as Int32 values (times too, but dates shall suffice for this example) i.e. 20090101 for Jan. 1st 2009. I can not change the schema of this database because it is still accessed by the old programs. However I want to write a new program using EF as the O/R-M. Now I'd love to have DateTime-Values in my Model. Is there a way to write a custom type and use this as a Type in the EF-Model. Something like a Type "OldDate" with properties: DatabaseValue : Int23 Value : DateTime (specifying the date-part whereas the time-part is always 0:00:00) Is something like this possible with the EF-Model ?

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  • Find Date From Non Contiguous Ranges

    - by AGoodDisplayName
    I am looking to find an best way to find a date from date ranges that may or may not be contiguous (I am trying to avoid a cursor, or a heavy function if possible). Lets say I have hotel guests that come and go (check in, check out). I want to find the date that a certain guest stayed their 45th night with us. The database we use records the data as so: Create Table #GuestLog( ClientId int, StartDate DateTime, EndDate DateTime) Here is some data Insert Into #GuestLog Values(1, '01/01/2010', '01/10/2010') Insert Into #GuestLog Values(1, '01/16/2010', '01/29/2010') Insert Into #GuestLog Values(1, '02/13/2010', '02/26/2010') Insert Into #GuestLog Values(1, '04/05/2010', '06/01/2010') Insert Into #GuestLog Values(1, '07/01/2010', '07/21/2010') So far I can only think of solutions that involve functions with temp tables and crazy stuff like that, I feel like I'm over thinking it. Thanks ahead of time.

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  • Can I create a transaction using ADO NET Entity Data Model?

    - by Junior Mayhé
    Hi is it possible on the following try-catch to execute a set of statements as a transaction using ADO NET Entity Data Model? [ValidateInput(false)] [AcceptVerbs(HttpVerbs.Post)] public ActionResult Create(Customer c) { try { c.Created = DateTime.Now; c.Active = true; c.FullName = Request.Form["FirstName"]; db.AddToCustomer(c); db.SaveChanges(); Log log = new Log();//another entity model object log.Created = DateTime.Now; log.Message = string.Format(@"A new customer was created with customerID {0}", c.CustomerID); db.AddToLog(log); db.SaveChanges(); return RedirectToAction("CreateSuccess", "Customer"); } catch { return View(); } } Any thoughts would be very appreciated.

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  • Dynamic order by without using dynamic sql ?

    - by Rohit
    I have the following stored procedure which can be sorted ascending and descending on TemplateName,CreatedOn and UploadedBy. The following SP when runs doesnot sort records.if i replace 2,3,4 by columnname, i got an error message "Conversion failed when converting the nvarchar value 'Test Template' to data type int.".Please suggest how to achieve sorting. CREATE PROCEDURE [dbo].[usp_SEL_GetRenderingTemplate] ( @facilityID INT, @sortOrder VARCHAR(5), @sortExpression VARCHAR(100), @errorCode INT OUTPUT ) AS BEGIN SET NOCOUNT ON ; BEGIN TRY SET @sortOrder = CASE @sortOrder WHEN 'Ascending' THEN 'ASC' WHEN 'Descending' THEN 'DESC' ELSE 'ASC' END SELECT TemplateID, TemplateName, CreatedOn, ( [user].LastName + ' ' + [user].FirstName ) AS UploadedBy FROM Templates INNER JOIN [user] ON [user].UserID = Templates.CreatedBy WHERE facilityid = @facilityID ORDER BY CASE WHEN @sortExpression = 'TemplateName' AND @sortOrder = 'ASC' THEN 2 WHEN @sortExpression = 'CreatedOn' AND @sortOrder = 'ASC' THEN 3 WHEN @sortExpression = 'UploadedBy' AND @sortOrder = 'ASC' THEN 4 END ASC, CASE WHEN @sortExpression = 'TemplateName' AND @sortOrder = 'DESC' THEN 2 WHEN @sortExpression = 'CreatedOn' AND @sortOrder = 'DESC' THEN 3 WHEN @sortExpression = 'UploadedBy' AND @sortOrder = 'DESC' THEN 4 END DESC SET @errorCode = 0 END TRY BEGIN CATCH SET @errorCode = -1 DECLARE @errorMsg AS VARCHAR(MAX) DECLARE @utcDate AS DATETIME SET @errorMsg = CAST(ERROR_MESSAGE() AS VARCHAR(MAX)) SET @utcDate = CAST(GETUTCDATE() AS DATETIME) EXEC usp_INS_LogException 'usp_SEL_GetFacilityWorkTypeList', @errorMsg, @utcDate END CATCH END

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  • How to format TimeSpan in xaml

    - by biju
    I am trying to format a textblock which is bound to a TimeSpan property.It works if the property is of type DateTime but it fails if it is a TimeSpan .I can get it done using a converter.But i am trying to find out if there is any alternatives. Sample Code public TimeSpan MyTime { get; set; } public Window2() { InitializeComponent(); MyTime = DateTime.Now.TimeOfDay; DataContext = this; } Xaml <TextBlock Text="{Binding MyTime,StringFormat=HH:mm}"/> I am expecting the textblock to show only hours and mintes.But it is showing like 19:10:46.8048860

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  • B-trees, databases, sequential inputs, and speed.

    - by IanC
    I know from experience that b-trees have awful performance when data is added to them sequentially (regardless of the direction). However, when data is added randomly, best performance is obtained. This is easy to demonstrate with the likes of an RB-Tree. Sequential writes cause a maximum number of tree balances to be performed. I know very few databases use binary trees, but rather used n-order balanced trees. I logically assume they suffer a similar fate to binary trees when it comes to sequential inputs. This sparked my curiosity. If this is so, then one could deduce that writing sequential IDs (such as in IDENTITY(1,1)) would cause multiple re-balances of the tree to occur. I have seen many posts argue against GUIDs as "these will cause random writes". I never use GUIDs, but it struck me that this "bad" point was in fact a good point. So I decided to test it. Here is my code: SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[T1]( [ID] [int] NOT NULL CONSTRAINT [T1_1] PRIMARY KEY CLUSTERED ([ID] ASC) ) GO CREATE TABLE [dbo].[T2]( [ID] [uniqueidentifier] NOT NULL CONSTRAINT [T2_1] PRIMARY KEY CLUSTERED ([ID] ASC) ) GO declare @i int, @t1 datetime, @t2 datetime, @t3 datetime, @c char(300) set @t1 = GETDATE() set @i = 1 while @i < 2000 begin insert into T2 values (NEWID(), @c) set @i = @i + 1 end set @t2 = GETDATE() WAITFOR delay '0:0:10' set @t3 = GETDATE() set @i = 1 while @i < 2000 begin insert into T1 values (@i, @c) set @i = @i + 1 end select DATEDIFF(ms, @t1, @t2) AS [Int], DATEDIFF(ms, @t3, getdate()) AS [GUID] drop table T1 drop table T2 Note that I am not subtracting any time for the creation of the GUID nor for the considerably extra size of the row. The results on my machine were as follows: Int: 17,340 ms GUID: 6,746 ms This means that in this test, random inserts of 16 bytes was almost 3 times faster than sequential inserts of 4 bytes. Would anyone like to comment on this? Ps. I get that this isn't a question. It's an invite to discussion, and that is relevant to learning optimum programming.

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  • CMD file time not always matching windows explorer file time

    - by skyrail
    I have a set of file I need to set the created, modified and last access date to exif date taken value, after a copy between 2 folders (might be fat32 on memory card or ntfs on fixed or usb disk). When I copy a file, the date and time switch to the current date. Then I change all 3 dates manually, either with change attributes in windows explorer or far manager on the command line. To make it faster I wrote a batch script getting original file dates (with php and function stat), building a batch script that invoke nircmd setfiletime for each file. Then I apply this batch to the copied version. The operation is relatively fast and reliable. Unfortunately, a bunch of files have last access and created time different in cmd and windows explorer (1H difference). Very strangely, it happens with dates between november and february, which make the operation unreliable. Why is this happening, and how can I fix it?

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  • How can I get windows to release an IPv6 address

    - by Mark Robinson
    I have a windows system with an IPv4 address and an IPv6 address and I'm trying to figure out how to release my IPv6 address. I've tried ipconfig /release6 and I get this error An error occurred while releasing interface Local Area Connection : The system cannot find the file specified. An error occurred while releasing interface Loopback Pseudo-Interface 1 : The system cannot find the file specified. No operation can be performed on isatap.{6B874193-B28A-4446-B6E6-8ADAC22E5090} while it has its media disconnected. No operation can be performed on IP6Tunnel while it has its media disconnected. I still have my IPv6 address at the end. I can release IPv4 address using ipconfig /release

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