I have a program in where I need to loop though the entire dataset.datatable. I takes a long time. What is the alternative I can use to do the some job but faster?
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In my winform application, I have 2 datatables, both contains 37000 rows. Table 1 has 171 columns and Table 2 has 4 columns. A While loop runs to update values in Table 1 from Table 2 for 4 columns. A For loop runs inside While twice to update values. It takes more than 5 min to do so. which i think should be a task of 5 seconds.
Columns being updated are:
Int64 - 1 Columns
String - 1 Columns
[Code]....
from a performance point of view is it faster to work with linq to sql or dataset.datatable?
View 6 RepliesI've got a DataGridView control that is bound to a datatable. The first cell of each row in the DataGrid is a checkbox. When the screen loads all of the checkboxes are unchecked by default. I have a "Select All" button to check all of the boxes. This is performing very slowly when I have a large number of rows in the grid. If I have 1,000 rows it takes over 30 seconds for them all to be checked. When I had 5,000 rows I gave up after 5+ minutes with no result. To check all of the boxes I am looping through each row of the datatable and setting the first item to True:
[code]...
Since that yielded such slow results I changed the logic to loop through each row of the datagrid and set the cell to True but that took three times as long.
Is there a way to quickly "check all" on a large set of data?
while using VS 2008 SP1 for VB WinForm apps (on Win 7 Ultimate machine),I find that while the performance of VS 2008 is on the slow side, it is generally tolerable except for one thing: when selecting an image for a button, the "Select Resource" dialog will come up, and I choose "local resource", then Import. After navigating to the appropriate folder and selecting the desired image,I will almost always get the "hourglass" (now the blue whirly thing),and only after several seconds will the operation complete(i.e. the "Select Resource" dialog will show the image I selected,and then I can close it and be on my merry way). Typically while the whirly thing is going, the dialog box title will say "Select Resource (Not Responding)". Also on some occasions during the wait period, the Select Resource dialog will hide, and I will have to click the VS icon in the taskbar to make it reappear so the operation can complete.
View 8 RepliesI have built an application using VB 2005 express edition with backend Ms Access 2000. In main form(which is loaded on startup), I am having 9 datagridviews, each bound with databindingsources. I am refreshing this data every 15 seconds by refilling the table adapters and updating the datagridviews.Now, this access database is shared in the network and is accessed by about 5-6 users concurrently. There are other forms which are used to edit the data.My problem is poor performance of the application. Its very slow in opening up forms, not responding sometimes and using the network resources fully.
View 5 Repliesi have a datagridview which have 3 columns, two button columns increase or decrease, 3rd displays the value increased or decreased from button. i have datagridview_CellContentClik behind button columns. The problem is increase in value on pressing button is very slow. i mean if i press button quickly the value should increase quickly but its the same slow pace for increasing or decreasing value on pressing button.
View 2 RepliesWe have a project for a client that is written in VB.NET. In one of the projects, we have about 100 modules, which are all VERY simple. They're extension methods that convert between object types. Here is a small snippet:
Public Module ScheduleExtensions
<System.Runtime.CompilerServices.Extension()> _
Public Function ToServicesData(ByVal source As Schedule) As ScheduleServicesData
[code].....
I am new to the world of VB.NET and have been tasked to put together a little program to search a directory of about 2000 Excel spreadsheets and put together a list to display based on the value of a Custom Document Property within that spreadsheet file. Given that I am far from a computer programmer by education or trade, this has been an adventure.
I've gotten it to work, the results are fine. The problem is, it takes well over a minute to run. It is being run over a LAN connection. When I run it locally (using a 'test' directory of about 300 files) it executes in about 4 seconds.I'm not sure even what to expect as a reasonable execution speed, so I thought I would ask here.The code is below, if anyone thinks changes there might be of use in speeding things up.
Private Sub listByPt()
Dim di As New IO.DirectoryInfo(dir_loc)
Dim aryFiles As IO.FileInfo() = di.GetFiles("*" & ext_to_check)[code]....
DataTable1“ About 16 000 entries“ coming from SQL[code]...
I have tried using a NOT IN clause in my SQL query with all the entity numbers from table 2 in that query but it takes over 10 minutes to execute.
Using a For Each loop and comparing each row takes about 3 minutes
i have a datatable with about 10000 rows and few columns (4)I have noticed that the process of reading a big table its quite slow..is there a way to improve performance in reading a datatable?
View 15 RepliesI have a dataset in a Visual Studio 2010 Web App project which accesses the DB with a complex SQL statement. If I run the statement in SQL Management Studio directly, it loads in a less than a second. If however, I run it using the "Preview Data" button in the dataset designer, or I try to access it on a page (with a gridview for example), it takes over 40 seconds!
View 2 RepliesI am calculating the average of an array(double) using a known (smaller) array of integers, which contains the indices for the larger array to give the values for the average. Below is the function:
'
'NumLoops = Ubound(LookupList)+1 !
' i always >0
Function Mean(ByRef Y() As Double, ByRef LookupList() As Integer, ByVal NumLoops As Integer) As Double
Dim res As Double
[Code] .....
Stand alone performance (through a win32 project) form is very good for my project. e.g. a Y() = 50000 entries, LookupList=1000 entries, calculating the mean 1000 times take about 5 ms.
That beats a c++ function accessed through a rcw quite easily (takes >300ms). However, when I plumb this function into a larger project the performance drops off significantly, taking (typically) 50ms for the same test. Also if (say) I make Y bigger (say, 100 000 elements) with everything else the same I see a tiny overhead in the stand alone test (of order 1 ms), yet I see a close to linear increase in the calculation time in the larger project. The larger project is not so big (a few MB) as to make we worry about resource constraints.
I have a simple code that looks up a text file, reads the line of text, splits the string by semi-colons and then posts the results.
After it has done this, I have created a really simple while loop to waste 10 seconds before going for it again.... here is the code:
Private Sub checkTemps()
While Abort = False
Try
[Code]....
I am trying to display value of the field ("UserID") for every row exists in datatable to checkboxlist(make the checkboxlist item selected).
I used for loop, but only the field value from last row of RoleUsers table is selected in the checkboxlist.
Here is my code
Private Sub DisplayRoleUser()
Dim conn As SqlConnection
Dim cmd As SqlCommand
[Code].....
The project is a web app in ASP/VB.net. The issue is that some pages are mind-boggingly slow. After trying to track down the bottleneck, it was discovered to be the load method when filling a datatable with query results.
We are using an Oracle database and queries are executed in stored procedures. As an example, we have a relatively simple select statement within a procedure which returns 2 columns with 6 rows which was determined to take about 0.015 seconds to execute. However it takes on average 7 seconds to load the OracleDataReader into a datatable - a ridiculous amount of time for such a small record set. After messing around with the query, I found that a simple decode statement appeared to be causing the issue. The decode statement is used similar to as follows[code]...
The iBln variable is simply a number being passed in to act as a boolean variable for determining which column should be between two dates. If I comment this decode statement out and make it simply "column1 BETWEEN iDate1 and iDate2" then the load method takes no time at all as it should, signifying that it is indeed the decode statement causing issues.
When the user clicks an "Edit" button on my form, I want a box to come up which allows the user to edit a DataTable in a strongly-typed DataSet. What's the best way to do this?
View 2 RepliesI have code running in the Datatable.ColumnChanging event in my dataset. This dataset underlies a form and conventional drag/drop controls are in place for data entry.when the event triggers and runs, I am running code in the form that checks the dataset.HasChanges property. It is showing False. But this is immediately after the ColumnChanging event has been triggered.Okay, I see by others posts and MSDN that .HasChanges will only be true after moving off the row with the changed column. I have also noted lots of discussion about the advanced binding property of DataSourceUpdate Mode, but that does not address this issue.I guess I can do this by checking the state of the row for the binding source. Just seems odd that the event behind the dataset can be triggered and that does not change the dataset.HasChanges property.
View 3 RepliesI have a dataset with around 15 table adapters. Everytime I make a change, such as add a column, change a type, or just anything, it takes around 3-4 minutes before studio responds again. The processor and ram are in good shape, but there is a spike in network usage by devenv during this time. In fact, devenv has the higheset network usage all together, even with with IE open and browsing. Why would this be and is there any remedy?[code]...
View 3 RepliesI want to import data from excel and move that to Datatable in VB.NET 2008. I wrote and working but its taking too long time.. for 1500 records its taking 4.40 min.
[Code]...
Which one is more faster between DataTable and SqlDataReader while I'm trying to fill Data into FlexGrid with VB.NET?
View 3 RepliesI have a For/Next Loop that adds values to column in a DataGridView. I want to set up a timer to slow the For/NExt Loop down. So the DGV will load and then the user will click button on the form and the DGV will have numbers added into all the rows of a specific column. For simplicity, assume I want to load the numbers 1-100 into each cell and I want to see each number as its passed.
I am not sure how t set up the time to work with the For/Next Loop in the Button1_Click event. Do I have to use a Timer1_Tick event as well and somehow associate it with Button1_Click event?
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[Code].....
1. load gridview from an uploaded excel file (this would probably be about 300 records or so)
2. compare manufacturer, model and serial No to my MS SQL database (about 20K records) to see if there is a match.[code]is there a better way to find a match between the two?
how to copy data from datatable to table in dataset i ry this but its readonly property
ds.datatable1=newdt.copy
I'm currently working with a gridview that has a huge underlying dataset.I'm almost certain that I saw something about a new facility in Visual Studio 2010/.NET 4, which would improve the performance (e.g. doesn't download all the data on databind, but rather only what data required for current page). My guess would be that it was using AJAX.I didn't need it at the time I saw it, and now I can't find it, even though I've been hunting online for a while.
View 2 RepliesI am having dataset with 5000 records.I am reading them in the below 2 functions and writing to excel.
FillDataRows1(worksheet)
FillDataRows2(worksheet)
private sub FillDataRow1(byval ws as worksheet)
[code]....
When I create thread also it is taking same time .
I fill data in C1FLEXGRID from DataTable using for...each loop with DataRow and DataRowCollection but it gives output very slow. How can I solve it.
View 1 RepliesI have two Datagrids, One grid has all the customers garments on it with style number and contact length. The other grid has the users who have garment issued to them. the style number is in both grids. I need to loop through the users grid and say if the contract number is 1 from the first grid then the contract date on the second grid will be todays date + 365 days (year contract) I have looked at using a stored procedure and also a for each command but I am just getting stuck with it all. [Code]
View 1 RepliesI just converted my project from VS 2005 to 2008 and started getting really bad lag only when intellisense iterates my dataset objects. The cpu maxes out one of my cores for about 2-3 seconds each time the intellisense list pops up. Is this a new feature of the 2008 ide?
View 19 RepliesAn in-line table valued function in SSMS takes about 6 seconds to return 11088 records. The same function in VB .Net 4.0 using TableAdapters.InputTableAdapter.GetData (Created with data set designer) takes about 15 minutes complete.Both are executed from the same workstation.Why does this discrepancy exist?
Workstation:
Windows XP SP3, 2GB
VS2010 Ultimate
.Net 4.0 Framework
Server:
SQL Server 2008
