What's The Fastest Method To Retrieve 1 Row From Database - ExecuteReader()?
Nov 16, 2010
I am trying to complete my function below but got lost in the different methods out there. It will always return 1 row and I need to get the values of the record and ADD into a new row. The function returns a DataTable.
I have one main doubt for long perioad, If we access the DB using SqlDataSource and ObjectDataSource, Can i know which is the fastest accessing the DB.
I'm using Webservice which will return the data from the database through datatable and I'll convert the datatable into byte array. In front end, I'll reconvert the bytearray to datatable and used ajaxloader to display it in the form.. It is dynamic loading. So, for each click, it is taking 10 seconds to retreive the data regardless of the size of the data. So, I used static datatable and I've loaded all data in that datatable in page load event. But, no reaction. It is taking only same time. Even, there is no data to retreive, the ajax loader is going on loading for 10 seconds. Problem is with Ajax or my webservice?? Plz, tell me some other idea??!!
I've an arraylist having 30000 items in it, what's the best way of creating a text file on the fly from an ASP.NEt page? Currently I'm using the code below but it times out with large data,
Using fileStr As New FileStream(sFileName, FileMode.Create, FileAccess.Write) Using writer As New StreamWriter(fileStr) writer.WriteLine("Error Messages") [code].....
I'm trying to optimize my ASP.NET thumbnailing script, so it doesn't resize all the images all the time, and one part of the problem is choosing the hash function for the thumbnail naming/checking procedure.Is crc32 up to the task - I'm asking cause the input data is small(only relative path, size and date)?
I have a bytes of data. Eg : 1024 bytes. And in that, say "Name Age Occupation" etc. All are only values. I have another skeleton xml which will have the <Name/><Age/> etc.
I need to loop through the bytes, say first 5 bytes is Name, Next 2 bytes is Age etc and fill up in this XML. I'll have 1000s of records and so need to know which way is the fastest.
Will the code be fastest or is there any way i can do by XSLT or similar component?
Is there any method by which we can retrieve random data from a dataset or rather directly from a table.
For example, I have around 30 questions in my table, I just wanted to display 20 among them and that too in a random order without the same item repeating. Can we achieve this using SP or through some Dataset manipulation?
I am a .NET / C# back end guy. I am working on a app that will have about 200 different data entry screens. For me exposing DTO as a collection for CRUD (IUpdatable and IQueryable) is the easy part, I can do it in my sleep :-). What I am trying to decide is what type of front end technology will allow me to develop these data entry screens fast. They don't have to be fancy but they are not just plain grid either and on average they have about 15 form fields and some client side data validation (no db look up) Options I am looking at are
Use ExtJS on the front and REST / JSON on the back. ASP.NET RIA but I do not know SL (Well XAML) Plain ASP.NET / MVC One idea I had was the DTO will contain the meta data about the form (As Attributes) and the form can be dynamically generated, but I do not want to reinvent the wheel if there is an easier way. I have looked at RAD software but all of them look at the DB and generate screens. I'd rather want something that can look at my DTO and generate screens.
I am trying to run a linq query but I need the result as a datatable as I am using that to store records from different queries in the same viewstate object.The 2 versions below compile, but return an empty set. The exact error is "Value cannot be null.Parameter name: source". (and yes I have checked there is data):
MyDatabaseDataContext db = new MyDatabaseDataContext(conn); IEnumerable<DataRow> queryProjects = (from DataRow p in db.STREAM_PROJECTs.AsEnumerable()
What I want to do is Pass data with GET/POST method from WinForm to WebForm and retrieve it. I know how to send the Datads using Winform. How can I capture those data using webform so that after i get the submitted data from the winform I can perform my querys .
i have created a table in sql server 2005 with two fields ImgId and ImageURL,where ImgId holds the serial number and Image URL holds the URL of the image file about where it is located in my hard disk.
Now i want to retrieve images from the database using its filepath.
I think i had done everything right,I tried to retrieve images in a gridview but dont know why it doesnt shows anything when i build the code.
I'm using data access block [URL] in asp.net 3.5. Back end is sql server 2005. It's working fine and returns result instantly for all DB calls. But, I've a problem with one SP. When I call it, executereader is taking too much time. In few cases, it is executed. And sometimes I get the Time out error. I run the same SP in sql server. It returns 9000 rows in 3 seconds.
Dim reader As SqlDataReader reader = cmd.ExecuteReader Dim XML As String = reader("records").ToString
I've executed the command in SQL server and I get a result string with length of 54781But when I execute it via .NET and assign it to the XML variable, the length of XML is always 2033...so now Im thinking that the result column "records" cannot exceed this length for some reason...
using (SqlDataReader sqlDataReader = ExecuteReader(CommandType.StoredProcedure, StoredProcedures.AuthenticateUser, sqlParameter)) { isAuthenticated = Convert.ToBoolean(sqlParameter[2].Value); if (isAuthenticated) { if (sqlDataReader.Read()) { User = new UserEntity(); DbHelper.GetEntity(sqlDataReader, User); } } }
I always get isAuthenticated as false because sqlParameter[2].Value is null all the time but when I execute my query with ExecuteNonQuery it gives me the value but in that case I can not fill the entity.
After trying many solutions listed on the internet I am very confused now. I have a C#/SQL web application for which I am simply trying to bind an ExecuteReader command to a Dropdownlist so the user can select a value. This is a VS2008 project on an XP OS.
How it works is after the user selects a table, I use this selection as an input parameter to a method from my Datamatch.aspx.cs file. Then this Datamatch.aspx.cs file calls a method from my ADONET.cs class file. Finally this method executes a SQL procedure to return the list of columns from that table. (These are all tables in Adventureworks DB). I know that this method returns successfully the list of columns if I execute this SP in SSMS. However, I'm not sure how to tell if it works in VS or not.This should be simple. How can I do this? Here is some of my code. The T-sQL stored proc:
CREATE PROCEDURE [dbo].[getColumnNames] @TableName VarChar(50) AS BEGIN SET NOCOUNT ON;
[code]...
The CreateLabels method above correctly shows me the labels. But the CreateDropDownLists method just shows me one dropdownlist with nothing in it. In other words, it is not selectable. So how can I verify that the datareader is returning all 4 columns and inspect their values? I was able to find from datareader "COLUMN_NAME" but I don't know what properties to search to verify the column names.
I am having problems with the following. On debugging I find that when strKeywords = '', reader = "System.Data.SqlClient.SqlDataReader". However, as soon as strKeywords takes the value of anything else, reader = nothing. But the stored procedure handles the arguments fine, so I am very confused!
Note: You may not need to read the whole thing to know what's wrong... skip down to the part about the 3 scenarios if you'd like. Only read the begin if you'd like some background info on how I've tried implementing this and where the errors occurred.To begin with, I'm trying to retrieve a list of Clients stored in the CRM_Clients table for a given callerId.I retrieve the clients from my Controller with the SelectLiveClientsForCaller method. The message is then passed on to the DAL through the static Instance method in the DataProvider class:
public List<Client> SelectLiveClientsForCaller(int callerID) { List<Client> results = new List<Client>();
I have a FormView through which I set up the default new, update and delete commands for communicating with an SQL Server database. When the CREATE command is executed the data is added to the database and some images are uploaded to a server and linked to the database.
When I press the Visual Studio's default FormView DELETE command I obviously only delete the selected row in the database and not the images on the server. I marked the uploaded images with images ID + "name" , so I could delete them if I could only retrieve the ID of the row being deleted by the DELETE command. How do I do retrieve the ID of the deleted row in C#?
I have a question regarding how to retrieve an mp3 file stored as a byte[] array from the database and display it in a form and let the user to download/play it?