Datareader And Empty Records?
Jan 26, 2009I 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?
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How To Identify Empty Records In A Database
Aug 27, 2011I am a newbie using Visual Basic 10 (Visual Studio 2010) and I am having a hard time working with my database. I have a table, let's say, TableEmployee with Fields Name and Position. On the Position Field, some of the records there were empty.My table is displayed in a datagrid and what I want to do is to insert a code that will identify whether the record under the position field is blank/empty and if that condition is true then display a messagebox that says "the particular record is empty"
View 7 RepliesVS 2010 : Create Multi-dimensional Array From Datareader From Datareader?
Feb 20, 2012I 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
Datareader - Error - "there Is A Datareader Associate With This Connection That Need To Be Closed"
Aug 17, 2009I 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"
DataGridView - Convert Nulls To Empty Strings And Display It In The Grid As Empty Strings
May 14, 2009I have a DataGridView that has some columns with dates. It binds to an in-memory Datatable which gets loaded from an string array of data passed back from the backend Some of the rows returned have nulls for the date columns. Solution 1: If I define the Date column in the DataTable as "string" I can easily convert those nulls to empty strings and display it in the grid as empty strings (desired results). However, if the user clicks on the date column header to sort by date, it doesn't order the rows as you want. You get a purely string sort order. Not acceptable
[Code]...
Can Retrieve Records From Database Fine / Having Trouble Updating Records
May 17, 2006I can retrieve records from my Database fine, but I'm having trouble updating records. I am getting a syntax error on [code] I get this error when I change the Last Name (Row 0, Column 1). [code]
View 4 RepliesGet Records Into Oracle Database Delete From DB And Update The Records?
Oct 27, 2009how to get records into oracle database delete from db & update the records i have successfully connected my vb 2008 win form with oracle 10g.
View 1 RepliesUpdate Records In A Dataset With Records In A Transaction File?
Dec 29, 2011How do I update records in a dataset with records in a transaction file?
View 3 RepliesNothing Equals String.Empty, Null Does Not Equal String.Empty?
Jun 28, 2010This must've have been asked before but I couldn't locate it. In a mixed code project (VB and C#) we were debugging some old Visual Basic code where a statement as follows could be found:
If Request.Params("xxx") <> "" Then
'do something
I considered this a bug as Request.Params could be null, in which case the statement would've become false which wasn't the idea. So I thought. I just found out, -- probably for the tenth time and I will keep forgetting -- that the following two statements are not equal, while Nothing in VB should be equal to null in C# (thought I):
if(String.Empty == null) // always false
If String.Empty = Nothing Then ' always true
Should I dismiss this as a typical Microsoft backward compatibility effort, or should I consider this a huge error in the VB.NET compiler? Does anybody know the Microsoftean opinion on this oddity?
Access - Search The Records And Display The Records?
Feb 9, 2010I want to search the records from the textbox and display the records to the datagridview, if there are no records, just display empty on the datagridview.
this is not working:
Dim sqlsearch As String
sqlsearch = "SELECT * FROM setting WHERE mname LIKE '%" & TextBox.Text
[code].....
Insert Records Into One Table Using Records From Other 3 Tables?
Mar 27, 2012I have this piece of code wich works perfectly when inserting records into one table using records from another table. My question is that now i need to create another table by using records from 3 other tables (tables are related). Can i use aliases on the column names, like on Oracle SqlPlus? How will be the syntax of the 'INSERT INTO SQL statement?
Dim MyConn As ADODB.Connection
Dim MyRecSet As ADODB.Recordset
Dim tmpSQL As String
MyConn = New ADODB.Connection
[code]....
VS 2008 Duplicate Records/Deleting Records?
Apr 17, 2010I am working on creating a program that records animal data (wombats) and stores it into a database, using vb.net. I am trying to add new records into a database but every time I click add, to execute that, there are duplicate records that gets added. How do i write the code so itonly adds it one time. I am using a data reader. Here is the
[Code]...
.net - Datareader In VB And SQL?
Jun 22, 2010i 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]...
.net - Going Through A DataReader Twice
Mar 30, 2011I 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?
Using DataReader In .NET
Jul 6, 2011I 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]...
Search Records And Display Records
Mar 11, 2010I want to search the records from the textbox and display the records to the datagridview, if there are no records, just display empty on the datagridview.[code]
View 8 RepliesArrays - If Not String.Empty Ignoring Empty String
Aug 11, 2010I have a array of strings and I am looping through them, but the string might be empty so I am trying this:
[Code]...
Add A Value Manually To DataReader ?
Jun 10, 2011I 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.
How To Loop A DataReader
Mar 18, 2009If 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]....
Only The First Record To Come In Datareader?
Sep 21, 2009I 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"))%>
Sql - Use Datareader While Getting A Value To The Textbox?
Apr 26, 2011Hey 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 ?
Dec 12, 2009two DataReader in one TreeView ?
VS 2008 Using A DataReader
Jan 27, 2010I 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.
.net - Fill DataTable From DataReader Row By Row
Aug 25, 2010i 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].....
.net Datareader Already Open Error When Not Used Before
Jun 22, 2011I 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?
Any Way To Reset Or Clear DataReader?
Mar 6, 2012Is 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 RepliesBig Performance With Oracle DataReader In .Net
Nov 10, 2010I 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 RepliesCheck Whether DataReader Has Data Or Not?
Nov 28, 2009Again 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]...
Compare A Textfield With The Value Of A Datareader?
Aug 1, 2011This 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.
Compare Date In .net Using Datareader?
Aug 8, 2011i 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 Replies