Store 2 Or More Resultsets In A Datareader?
Oct 5, 2009Is it possible to store 2 or more resultsets in a Datareader? I have different methods which each return a DataReader. Can I store resultsets of them in the same DataReader?
View 1 RepliesIs it possible to store 2 or more resultsets in a Datareader? I have different methods which each return a DataReader. Can I store resultsets of them in the same DataReader?
View 1 RepliesWe have an item cull that retrieves items and their appropriate data from one server. Their Primary Keys need to be INNER JOINed with another table. However, the second table is on another server. We can retrieve that data using a separate select statement and accompanying VB objects.
How would one go about this programmatically in VB? Is a loop the best practice available? Although we are in a Microsoft Ecosystem, Server Linking is not possible.
I have an SQL statement like:
SELECT FNAME, LNAME, CITY from EMPLOYEE
How do I create a multi-dimensional array from a datareader which should store values like:
John, Doe, LA
Mike, Johnson, PASADENA
Freddy, Kruger, Long Beach
Stackoverflowers,I have a resultset from a SQL query in the form of:
Category Column2 Column3
A 2 3.50
A 3 2
[code].....
I have a problem with my project. here is the problem:
My code for login is as follows:
dim conn as SqlConnection = New SqlConnection("Data Source.................)
dim cmd as SqlCommand = New SqlCommand("Loguser",conn)
cmd.CammandType = CommandType.StoredProcedure
[CODE]...
Now the error i get is that "there is a datareader associate with this connection that need to be closed"
I am coding a program that will allow the user to input 5 payrolls for Store 1, Store 2, and Store 3. The total of the 5 payrolls are then added together and shown in the respective Store's labels. A total label is also there to add up all the totals into one number. The numbers in the label must be in currency form. My problem is the numbers don't add correctly when I hit calculate. The first two numbers add together, but then after that the number just seems to subtract a random amount.
So far I have this --
Public Class Form1
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Me.Close()
End Sub
[CODE[...
i know that integer is a variable to store whole numbers and that a string is a varialbe used to store any text, but what variable type would you use to store a number that has decimals?
View 7 Replies"Create a class called Invoice that a hardware store might use to represent an invoice for an item sold at the store. An Invoice should include four pieces of information as instance variables--a part number (type String), a part description (type String), a quantity of the item being purchased (type Integer) and a price per item (Type Integer). Your class should have a constructor that initialize for each of the four instance variables. Provide a property for each instance variable. If the quantity is not positive it should be set to zero. If the price per item is not positive it should be set to zero."
I attached the code I have. obj is underlined and says "Argument not specified for parameter 'Invoice4' of the 'Public Sub New (Invoice1 As Object, Invoice2 As Object, Invoice3 As Object, Invoice4 As Object)' and so the program won't run. What am I doing wrong?
Public Class Form1
Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
Dim obj1 As New Invoice(Val(TextBox1.Text))
TextBox1.Text &= obj1.Invoice1 & vbNewLine
TextBox1.Text &= obj1.Invoice2 & vbNewLine
TextBox1.Text &= obj1.Invoice3 & vbNewLine
TextBox1.Text &= obj1.Invoice4 & vbNewLine
[CODE]...
i am working on a search feature for a program i am working on and i found a tutorial online that provides some insight but the actual code, after being modified to fit my aplication, does not work. i get two different errors as of right now, one that tells me "the value of type 'System.data.sqlclient.sqldatareader' cannot be converted to '1-dimensional array of system.data.sqlclient.sqldatareader" and the other that says"argument not specified for parameter 'array' of 'Public shared function... anyway i am kinda new to this and here is what i have so far. any advice?
Private Sub SearchOKButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SearchOKButton.Click
[Code]...
I have the following code which does what it's supposed to do:
objSQLCommand = New SqlCommand("select * from table1", objSQLConnection)
objSQLCommand.Connection.Open()
objSQLDataReader = objSQLCommand.ExecuteReader()
While objSQLDataReader.Read()
[Code]....
But I need to loop through the objSQLDataReader 1 more time. How would I do that?
I got the error message There is an open data reader associated with this command which needs to be closed first by using the following code:
myCommand = New SqlCommand("SELECT BookCode FROM tblBook",myConnection)
myReader = myCommand.ExceuteReader
While myReader.Read
[Code]...
I am copying sample.csv file's content into the new.csv file. But I need to add additional column in new.csv file which holds the default value as "Yes" for each row that exists in old file. Here is the code I have written.
Dim ioFile As New System.IO.StreamReader("C:sample.csv")
Dim ioLine As String
Dim ioLines As String[code].....
The first four columns ID,Name,Number,Amount are present in sample.csv.I am adding additional column Copied which should be "Yes" for each row.
If my Select statement finds data that matches the criteria, how do I get myReader (DataReader) to read each record when there are more then one record found?
Dim myReader As MySql.Data.MySqlClient.MySqlDataReader
myReader = myCommand.ExecuteReader()
If myReader.Read() Then
[code]....
I am trying to tag of some words.There are 5 tag word in my database. but only the first record is coming.i want to
my codes
Public Function tags(ByVal ID As Integer) As String
[code].....
my html code in gridview <%#tags(Container.DataItem("ID"))%>
Hey Friend i am using a form with a *combobox*in which the items i have taken from the
sqldatabase named as balance and that sqldatabase have two columns one is customername and the
another is obbalance now .
In the form i had binded all the customer names from the table and now i have a textbox i want to do is
when the user selects the combobox.selected item any one customer name i need to display the obbalance of the selected customer in tat textbox
[Code]...
two DataReader in one TreeView ?
I am working on a project which requires me to connect to a MySQL database. From there I query the database and need to do work on the returned values.
I can query the database just fine. However, now I need to do work on the results. The two columns returned are user_name and user_password. The rows are the user accounts. I would like to take my query results and put each column into its own arrary().
[code..]
Instead of writing the results to the console, I would like to write each column to an individual array. Is there an easier way to accomplish this task? Or, what is the code I must place within the loop to do this.
i want to fill a Datatable with a Datareader row by row but get an exception because the reader's columns have a different order than the Datatable's columns.
Why and how does a Datatable loads itself with a Datareader correctly, even so it has a column collection with different order?
I need to calculate values for every row so i dont want to load the Datatable completely but row for row. It has 25 columns so i dont want to set it all manually.
There must be a chance to load/fill/add a new row from a datareader without having the same column order(reader.GetSchemaTable?).
Following is what i have but what doesnt work:
Using reader As System.Data.SqlClient.SqlDataReader = command.ExecuteReader
'next line works(configInfo.DataSource is a Datatable)but is inappropriate
configInfo.DataSource.Load(reader)
[Code].....
I have this sub as part of my login / logout system. When this sub is called to login users it works perfectly, but on logout it throws an error that doesn't make any sense to me.
[Code]...
This sets a nonsense email address so that when validate_session searches for a valid email/session combo in the db it trips the destruction of the sensitive session data.
The question boils down to this: Why is the error being thrown when the logout sub calls validate_session?
Is there an easy way to reset or clear a DataReader so it can be read through more than one time? I found a Close method but not an open method.
View 1 RepliesI have a few Oracle procedures that generate/return a large amount of data that I need to write out to a file.I'm currently trying to accomplish with a data-reader. It seems to be working, I've successfully generated a 479mb file without any trouble.It took less than 4 minutes from the time I retrieved the dataReader to complete the file.But the dataReader I get for a particular procedure is crawling.It's unbelievably slow.I modified my code to try and get a better idea of what is going on[code]I'm writing a PL/SQL block that will open that cursor to see if the performance issue exists when I remove the .Net code..
View 3 RepliesAgain I have problem with checking whether DataReader object has data or not?
Dim cmd as SqlCommand
Dim drd as SqlDataReader
cmd = New SqlCommand ("SELECT * FROM Stock", conx)
drd = cmd.ExecuteReader()
[Code]...
This may perhaps be a stupid question but I just can't get it to work.
I have an if clause where I compare a textfield with the value of a datareader.
It looks a little like this if me.txtfield1.text <> reader("field1") OR me.txtfield2.text <> reader("field2") ETC... I do this for a lot of field.
But now I want to check if field2.text is string.empty and if it is I want to skip the comparison for that field.
i want to compare two data values in my database.These two dates belong to two different columns.What i want to compare is if the date of one column greater by 6 months from the date of other column then it should give error.I want to pass this query to database and check,and later on depending on the result want to insert my other functionality?
View 1 RepliesI have a form in where I work with some data readers. One of my readers only gets the information from the first row. When ever I try to get something from the second row onwards I get an error saying that "no data found in row". I am using "ExecuteReader" not "ExecuteScalar". I cannot understand why I get this behaviour. Here is the The reader that gets me this error is reader2.
Dim reader As OleDbDataReader
Dim reader1 As OleDbDataReader
Dim sql5 As String
Dim SQL As String
sql5 = "SELECT * FROM Services WHERE ServiceID = " & Me.ServiceIDTextBox1.Text & ""
[Code].....
I have a sql query that sometimes returns nothing...not null, just nothing.
This is causing my datareader to error out.
Is there a function, like isDbNull, but is for empty recordsets?
I try to create a funtion to return a datareader from CSV file as below but got a error said that
ERROR [IM002] [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified(at cn.open())
Public Shared Function GetCSVAsDataReader(ByVal csvPath As String) As Odbc.OdbcDataReader
Dim fi As New FileInfo(csvPath)
[Code]....
I want to load all of the LOCATIONS in the Location table to a Combobox and then for any found locations (in another table) to be deleted from that combobox. Im using a Array list, but can't get the Data reader to write to the Array list.
Dim SQL As String = ""
Dim Reader As OleDbDataReader
Dim i As Integer = 0
Dim LocationArray As ArrayList = Nothing
[Code]...
im converting my classic vb class into vb.net class and im having some problems with my object.Query function
here is my obj.Query Function
Code:
Public Function Query(ByVal sqlStatement As String, Optional ByRef e As String = "") As SqlDataReader
Try
[Code].....
There is already an open DataReader associated with this Connection which must be closed first.
the error fails when it trying to read this [code]...
Is there is a connection between the Datareader and in initializing the transaction?