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What is the error you are getting? Just telling us you have an error won't help.
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I forgot to display the error message, here it is:
Error while connecting SQL Server. There is already an open DataRedaer associate with this command which must be close first!
However, since I have to update that row before scan the next row (while loop), I can't close it ... may I need another cmd2.ExecuteNonQuery()? But then I need to connect database again?
Is there better command to avoid the abobe problems?
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When you use a reader, the connection is not closed while the reading is going on. Therefore you cannot use a different command associated with that connection to do the update.
Try to create a different connection and command to do the update.
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You are right, however my database is already open & connect ... now I have open & connect anothe one with the same database?
con.ConnectionString = strOpenSQLDatabase
con.Open()
con2.ConnectionString = strOpenSQLDatabase
con2.Open()
Is there other way around?
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Dim ra As Integer
Dim cmd As New SqlCommand
Dim cnt_del As Integer
Dim room_N As Integer
Dim str As String
con.ConnectionString = strOpen
con.Open()
cmd.Connection = con
cmd.CommandText = "SELECT * FROM Info"
'con2 should be declared somewhere
con2.ConnectionString = strOpen
con2.Open()
'cmd2 should be declared somewhere
cmd2.Connection = con2
Dim lrd As SqlDataReader = cmd.ExecuteReader()
If lrd.HasRows Then
Try
'Dim lwr As SqlDataReader
While lrd.Read()
ListBox1.Items.Clear()
str = lrd.GetValue(0).ToString() + ","
str = str + lrd.GetValue(1).ToString() + ","
str = str + lrd.GetValue(2).ToString() + ","
str = str + lrd.GetValue(3).ToString() + ","
str = str + lrd.GetValue(4).ToString() + ","
str = str + lrd.GetValue(5).ToString()+ ","
str = str + lrd.GetValue(6).ToString()
ListBox1.Items.Insert(cnt_del, str)
cnt_del = cnt_del + 1
ListBox_Available.Items.Clear()
room_N = SearchAvailableRooms(lrd.GetValue(2), lrd.GetValue(3), lrd.GetValue(4), lrd.GetValue(0), lrd.GetValue(1))
If room_N > 0 Then
cmd.CommandText = "UPDATE Reservations SET AvailRoomsRates = 'Trials'"
cmd.ExecuteNonQuery()
cmd2.CommandText = "UPDATE Reservations SET AvailRoomsRates = 'Trials'"
cmd2.ExecuteNonQuery()
End If
End While
lrd.Close()
Catch ex As Exception
cnt_error = cnt_error + 1
TextBox_Error.Text = cnt_error.ToString()
End Try
End If
con.Close() 'Whether there is error or not. Close the connection.
con2.Close()
I really don't know if there is an alternative to this. Sorry!
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I will use your update codes
There is an alternative, but I don't know which one is better regarding of process speed (considering there are many rows existed)
1. I move the update If room_N > 0 Then outside the while loop, in the loop I will put LOOP's str values into a string array, when Loop done ---> lrd.Close()
2. Then I use a While Loop to Update all rows from the array
*) This will avoid Open/Connect twice & Close twice ... but might it be a clumsy programming?
Thanks for help 
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If you use transactions on the second connection, the performance will be improved. I don't know how much improvement you will get. On a different database engine, I once improved the performance of a bunch of updates by over 100 times just by putting them into transactions.
Your solution of saving the stuff into an array and updating after the loop is also good.
Good luck!
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Then I will try both methods, the latter is just for curiously
Thanks & 
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Hi experts,
I have read that using a datasource with ADODC1 you can use text boxes to display the database.
I read that all you have to do is on the text box you just change the properties, datafiled and data source
so it would like
Data field = ID
and
DataSource = Adodc1
however the textbox doesn't display anything? THe database works fine, can anybody help?
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txtFirstName.DataField = "FirstName"
Set txtFirstName.DataSource = Adodc1
...
Set txtFirstName.DataSource = Nothing
Copied from an article[^] on databinding
I are Troll 
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Hi,
Can Anyone guide me with scenario below:
I have two applications A and B with its respective database. One table is the same by both applications. For example Officer Profile table. In application A, Officer Profile table get updated very often.
So I have a Connection button in application B to get the updated records from Application A ..
Once connected, I want to show all available tables. and I want to import a selected table.
I want to have a restriction whereas if table is not resided on both databases it cannot be imported..
Steps are:
Connection->select tables(ex.Officer Profile table)->Import table(ex.Officer Profile table)
Now Officer Profile table for database in application B get updated.
Hope I'm clear with my explaination..
Thanks in advance
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You want to synchronize tables that reside in different databases? What database are you using?
SQL Server[^] has good support for replication
I are Troll
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Hi,
Thanks for replying..
Visual Studio 2005 and Sql Express
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waner michaud wrote: Visual Studio 2005 and Sql Express
SQL Express cannot serve as a Publisher or Distributer, only as a Subscriber[^]. There's also the Microsoft Sync Framework to consider, but I couldn't find much examples on Sql Express[^].
The alternative would be to synchronize the data manually. There's a CodeProject article here[^] that explains how this could be done.
I are Troll
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Hi,
thanks again for the information you provided me..
Ok.for my purpose I only need to work with one table..
one table from the source and one table to destination..
destination table has no foreign key constraint..
OfficerTable on the destination database is solely there for searching..
I can do basecally anything on it such(del, alter, modify and so forth) since no constraint..
I think using a stored procedure will be ideal situation in my case..
The article is bit convoluted, with my very litle experience in sp..
can you lead me a bit so I don't get lost in a carbweb.. I do not like to waste valuable in something I am not good at..
Briefly, my cenario is as such, Open a connection, select OfficerTable from the source, send it to destination database which was the original point of initiating the connection to modify OfficerTable in destination.
Once again, I thank you..
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waner michaud wrote: The article is bit convoluted, with my very litle experience in sp..
No worries, experience comes from doing
waner michaud wrote: I do not like to waste valuable in something I am not good at..
If the client wants it, then somebody has to build it. Building yields experience and valuable knowledge.
waner michaud wrote: Briefly, my cenario is as such, Open a connection, select OfficerTable from the source, send it to destination database which was the original point of initiating the connection to modify OfficerTable in destination.
Let's make three scenario's out of that;
0) Records to be deleted from Destination database table
1) Records to be inserted into Destination database table
2) Records to be updated in the Destination database table
The link to the CodeProject[^]-article contains example sourcecode on performing those three steps using stored procedures.
I are Troll
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Hi,
Must I create a sp for delete, insert, and update that reside in the database for the destination table and as well in the source database?
Thanks
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waner michaud wrote: Must I create a sp for delete, insert, and update that reside in the database for the destination table and as well in the source database?
According to the article, you'd only have to create stored procedures for the destination database
I are Troll
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Hi,
Ok. since I need the destination table for search only. Can I just simply alter the destiantion table?
thanks..
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waner michaud wrote: Ok. since I need the destination table for search only. Can I just simply alter the destiantion table?
Would it be OK to overwrite the destination-table with the source-data? If that's the case, then DROP the destination table and do a SELECT INTO. That would create a new table, based on the data that the query returns.
If you want readonly remote access to a table in a different database from the same server, then a view could be another alternative;
CREATE VIEW [destinationDb].[dbo].[RemoteOrders]
AS
SELECT *
FROM [sourceDb].[dbo].[Orders]
I are Troll
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hi,
I am getting the concept of stored procedure a bit..I am going to create a sp to do DROP AND INSERT INTO.
which the following Should I do?
I am using dataset.
I will have a Connect_to_HNP_button. Once I establish a connection, I want to show all the tables. Select OfficerProfile_table, and then call the sp to import table.
Or on the Connect_to_HNP_button_click event call the stored procedure. Inside the sp, establish the connection, and then do DROP DESTINATION OfficerProfile_table, and INSERT INTO DESTINATION OfficerProfile_table FROM THE SOURCE..
Which way to go and how?
Thanks
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waner michaud wrote: Which way to go and how?
The second option: create a form, drop a button on it, and make it call a stored procedure. Create a table and see if you can drop it from code
I are Troll
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Hi,
Ok..I'll keep you posted..
Thanks
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hey experts
when i deploy my application on user system after that if i copy the installed application from program files and paste it on another system it runs without running setup. i want to make my application secure. how can i do this, waiting for help
i also want to use trial version and full version facility.
Regards
Narendra Singh
(Jindal Tech Ventures)
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Hi NarendraSinghJTV,
to make secure your Windows application you can use Windows registry editor. Code your application to check some values in registry to check whether the application is installed or cop-paste.
You can also use some temp files for the same.
For trial and full version application, you need to keep installed date of application in a secure file and check everytime current date when the application is launched. If current date is more then trial time then it should ask to enter key or something like that.
I hope you got what you wanted!
Gagan
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