DataSource Controls :: Getting A Single Value From A Returned Dataset?
Feb 18, 2010
I've managed to connect to the database and return a record based upon a login name. I can itterate through the rows printing out the password but I know there's only 1 row (or can test for that) so how do I get the value of the password for the one row without the loop?
Dim supervisorAdapter As New SupervisorTableAdapters.SupervisorTableAdapter
Dim supervisors As Supervisor.SupervisorDataTable
supervisors = supervisorAdapter.GetSupervisorByLogin(login)
For Each count As Supervisor.SupervisorRow In supervisors
Response.Write(count.password)
Next
I want to run a SUM on a particular against the DataSet returned by a SqlDataSource. How can I access the DataSet stored in memory that is returned by the SqlDataSource to run this calculation?
I am having some difficulties with a particular task. I am creating a support desk intranet application and I am trying to write a method within a class within a namespace which will form a generic database connection which can be called from any of the aspx pages so that I have the dbconnection logic in one place; you know, going along with the 'DRY' (Don't Repeat Yourself) mantra.
The Namespace:
SUPPORTDESK.SQL.dbconnection.pullData()
Objective of the method:
To provide any aspx code behind file with an SQL Server 2005 Express Connection and if possible return the data from an SQL Query. This is where I need advice do I create the method such that it simply forms the connection and returns a DataSet or that it returns an SQLConnection object? If i've got things back to front and upside down don't worry I'm a beginner with ASP.NET. The Method so far:
[Code]....
If I'm on the right track how do I access the data returned in the DataSet?
This may not be the correct place to put this as it is both a stored procedure AND Visual Studio 2008 problem.
I have the following stored procedure:
[Code]....
I have been mokeying around with it because of what is happening. I have a dataset, call it dataset1. I drag this stored procedure onto the dataset. I EXPECT a datatable to appear, instead the data set adds this store procedure to the queries table adapter and sets the exec mode to 'NonQuery' which unless I am very mistaken, means "don't expect a dataset back from this' when in fact you DO expect a dataset back from this.
The SQL server is a Windows 2000 Server running SQL 2000. It has never caused us a moments grief since we set it up oh-so-many years ago.
If I connect to a different database and drag a query into the same dataset I get a datatable as I expect. I cannot see where / how this procedure could be wrong. The query when executed returns exactly the data I expect, in the format I expect (looks like a table, acts like a table in the Query analyzer).
I have a stored procedure that returns 3 tables within the single recordset it returns. If I set a SqlDataSource to get data from this procedure, it works, but it only returns the first table. I want to have a GridView display the data from the 2nd or 3rd table using a SqlDataSource, but I can't figure out how to specify a particular table.
While there are some posts discussing this out there, I can't get a definitive answer about whether or not this is even possible (?). In a worst-case scenario, I can create another SP that only returns the 3rd table - but that creates a little maintenance headache that I would prefer to avoid.
For context: First of all, I am new to LINQ, as I have been using SubSonic for quite some time now.
I have two tables, Users, and Affiliates. They both have a very typical schema. The FK that joins them is the UserId field, which is in the Affiliates table. I want to create a LINQ query that pulls the Username from the Users table using the AffiliateId value. The AffiliateId is a primary key of the Affiliates table.
I have tried to accomplish this using many variations of the following code:
[Code]....
In the above query, I expect to get a single row result set. However, I instead receive the entire table of results.
How can I make this work? I have yet to see an example or article out there to do what I am trying to do.
how do i copy required row in dataset to a new dataset. i have bind a xml into a dataset and i need to display say row 3 to 5 only so i do a for loop but i have encounter problem when trying to copy the rows to a new dataset.
do i have to write the xml to datatable and bind it to dataset and from there copy over ?
I get a single value from a stroed procedure of type float. Even if I change it into Int or decimal in the procedure when I call it from my asp.net appliction with ExecuteScalar I get this error:
Exception Details: System.InvalidCastException: Object must implement IConvertible.
I need to know how to display a single row(or particular row)from dataset and display into gridview... i tried by using some codes, like the following, If strCourseLevelId <> "" Then Dim ds2 As DataSet Dim currentbundlenid As Int16 Dim prevbundleid As Int16 = "0" Dim bundlenos As Int16 = "0" Dim bundlecontent As Bundledata = New Bundledata ds2 = bundlecontent.GetBundleData(strCourseLevelId) If ds2.Tables.Count = 1 Then If ds2.Tables(0).Rows.Count > 0 Then With ds2.Tables(0) Dim strCnt As Int16 For strCnt = 0 To .Rows.Count - 1 With .Rows(strCnt) currentbundlenid = .Item("Bundleid") If currentbundlenid <> prevbundleid Then bundlenos = bundlenos + 1 End If If bundlenos = "1" Then GridView1.DataSource = ds2 GridView1.DataBind() ElseIf bundlenos = "2" Then GridView2.DataSource = ds2 GridView2.DataBind() ElseIf bundlenos = "3" Then GridView3.DataSource = ds2 GridView3.DataBind() End If prevbundleid = .Item("Bundleid") 'next write the main page content End With Next End With End If End If.
I have recently converted all my applications to framework 4.0 and am very happy as a whole.
I have, however, run into a bit of a bind: i have exposed quite a few web services that have methods returning datasets.
Clients immediately started complaining that the order of the tables within the returned datasets were different. I investigated and can confirm that the webmethods are indeed shuffling the tables within the datasets. The order of tables in the method result are markedly different from the table order in the code before being returned.
My question is: is it possible to hard code the order of tables within the dataset being returned by a webmethod? I know that clients should, ideally, be referencing the tables via the table names, but that is - unfortunately - not the case in the really real world.
using vb.net 2005 and crystal reports. in the vb.net code I am querying the database, processing the results and then binding to the crystal report.
What I need to do now in the code is this: I need to create a new page to display the results so that there is one page for each row in the dataset that I'm binding to the report.
im working on visual Studio 2010, and i have an error on an update.
this is the code in VB.
[Code]....
Thats the code and the error is:
Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression.`
When a sql query returns NULL , I can use the following code to evaluate:
[Code]....
When a sql query returns nothing, neither IsDBNull nor is Nothing works. I don't know why some sql queries return null while some return nothing when there are no data returned. But anyway, can somebody tell me how to evaluate nothing value returned in sql datareader in vb.net? When I put the cursor over signInfo variable in debug mode, I can see Nothing show as its value. But the line does not work
I am viewing items returned from a dataset in an Infragistics chart control. My problem is that due to a weak point in the control, I am left looking for a way to manipulate the height of the chart based on the count/number of items returned by the ObjectDataSource(DataSet).
Does anyone one have an existing C# sample they could let me view of accessing the count of records returned within the code-behind of a page that I could then use within a case statement to set the hight of the control?
I'm developing a website using asp.net 2.0 . I have retrieved a record from database through the query.
SqlConnection con = new SqlConnection(connectionstring); con.Open(); String SQL = "SELECT * FROM Table where attribute1 = value"; SqlCommand cmd = new SqlCommand(SQL, con); SqlDataReader reader = cmd.ExecuteReader();
Sometimes, there is no record matching this query and so null value is retrieved. My question is how to find that the null value is returned. Since If (no record found i.e NULL) certain actions needs to be done and if (records found i.e NOT NULL) ceratin different actions needs to be carried out.
I have a stored procedure 'RoomIfExists' on my sql server (it does work). It takes a string variable for the Room_No and returns either '1' or '2' depending on the result of the query.
[Code]....
I need to know how to run the sp in c#, passing the variable Room_No and then pull the result from it.I am using a data reader.
I'm attempting to further reduce a dataset/table by various user input. Part of this process is grouping the data by a timestamp prior to a summation. I'm trying to use LINQ and cannot get the data returned that I need.
string strConString = ConfigurationSettings.AppSettings[ "conString" ]; myConnection = new OdbcConnection(strConString); myConnection.Open(); // open connection string strSelect= "select * from tbl_howells_product_data where title like" + "'" + strsearch + "%" +"'" + "order by product_id asc"; OdbcCommand myCommand = new OdbcCommand(strSelect, myConnection); dtrReader=myCommand.ExecuteReader();
The problem is I need to check to see if any data has been returned from the SQL query, if there are no rows/ data returned by the query then I need to display a message to say that there aren't. I know that there isn't a 'number of rows method' for the dtrReader, so does anybody know how I could do this?
I now want to count the number of returned rows so that I can say:IF rows_returned = 1 then login else deny I think you get the idea.P.S. I know this is not the most secure method of login but I do not want to use the ASP.NET configuration manager as I like to understand what is happening. I am starting off very simple and I shall work up from there.
