Retrieve Last Row On Database To Be Able To Automate Primary Key Code That Been A Varchar(10)
Nov 10, 2011
i need a functionality that adodb.recordset have on ado.net right now im developing my project in school but seem to difficult for me to handle give me an idea what should im going to use here can i hindrance that made me stock.i what to retrieve the last row on the database to be able to automate my primary key code that been a varchar(10).i know some basic stuff on connecting thru ado.net,inserting,updating,deleting could you have some advice or post some example that might use of it..
Im trying to develop a frontend for a database project I have been working on, I am using a combobox to select a meal_name and need the primary key to update another table for orders, How can I retreive the primary key using the meal name selected.below is the code I am using to add meal names to the combobox
Private Sub ComboBox1_MouseEnter(ByVal sender As Object, ByVal e As System.EventArgs) Handles ComboBox1.MouseEnter Dim myRow As DataRow Dim CmdStr As String[code].........
when i will enter form no. in the text box this should check the on the lost focus event either this form no. is already exsist or not.if exist show msgbox?
I have seen several threads about automating several aspects of html elements (buttons, textboxes, checkboxes, radio buttons etc...) but I didn't see any specific codes to auto-click "Hyperlinks". How would I invoke a click on any hyperlink located on any given webpage if I needed to?
I have a report made in Crystal Reports XI. The report is generated and exported to PDF in visual basic script using COM interface. Generally everything is running smoothly, but in one case generation breaks with error: Failed to retrieve data from the database. Details: [Database Vendor Code 9421]
Database used is MSSQL 2005 connected over ODBC to CR XI. When I am opening report with exactly the same parameters in Designer, everything works fine.It looks like it is data related, but it is hard to trace since the whole report is pretty sophisticated. Anyway I spent half a day on crawling over Dr. Google and it seems that he has no clue what might be an issue.
My address from my router (primary address) is 192.168.1.25, or also it would be Dns.GetHostAddress(Dns.GetHostName).GetValue(4) which is the 5th element in the array If I'm obtaining a users local IP address on various machines with various amounts of network adapters, my program will break. I must know the IP of the primary Windows Ethernet/Wireless adapter in use.
I tried using the following codes but it's not working,
Dim Con As oledbconnection = new oledbconnection() con.connectionstring = "Provider = Microsof.jet.OLEDB.4.0; Source=c:\program file\database.mdb" dim sqlcmd as oledbcommand = new system.data.oledb.oledbcommand() sqlcmd.commandtype=commandtype.storedprocedure sqlcmd.commandtext = "query"
how do i search a varchar field in a sql database and get rid of the char unless it is an number 0 thru 9 and then add that number to the monthly calendar todays date to determine a due date?
I'm pulling records from a db table (sybase) where I have run into a problem with a long varchar field. Using the OLEdb class I convert the field into a string variable which works fine in most cases, but there are problem with a few records. Examining the field in the database it shows that the value is not null, but the length of the field is 0.(SELECT field, length(field) FROM table). When I try to convert this into a string the result is rubbish.strContent = objReader.Item(i). I can't figure out what's the problem here, so I have avoided the issue by doing a table update before I start the process of getting data (I set the field value to null if field.length = 0
I am new to vb 2008, but I know how to automate some html elements. The issuse that I running into is that I cannot get my webbrowser1 to auto-click the "Gmail" button at the top left of the page or the "Show me my account" button on the righthand side of the webpage. Here is the webpage that I'm trying to auto click: url...Can someone please view the html source and give a code sample to click either button so that the page can then go on to the following page?
On a client i have an anonymous list containing a multi-column primary key previously selected from the DB.Then i need to select all the records from the DB that equals the primary key list i have stored in the memory.[code]
where projectName is a String, and DbDataSet is my dataset. The variable projectId is the ID of the row I want to extract the data from, but every time I run my code I get a NullReferenceException.
I know that the row with the primary key value of projectId exists because I can see it when I view through server explorer.
So Im making a program with 2 different data tables where different columns from those tables are used in different tabs in the same form. This all works good and well so far, but I have one issue which just drives me mad, and a couple minor ones.
1. I have an ID column in each data table marked as Primary Key, Unique and Identity. Problem is that even if I choose to hide this column it just randomly decides if it actually is visible or not. Most often its visible. I dont get it, doesnt this function work? Do I use it wrong? Im not using any code for this, just right click on the data grid, press Edit Columns... And change the Visible to False. It works for all other columns all the time as far as I can tell, but for my ID column its just random.
2. Im wondering if its possible to align the text in some of the columns of my data table to the right, note I only want some of them, not all of them.
3. Is it possible to do maths with the values from the columns in a table on the same row? Like for example having column 3 = column1 + column2?
I'm creating a form that will be used to update fields in a table. I don't want the user to be able to update primary keys though, so I'm trying to disable the textbox so it can't be edited.
The textboxes are created during runtime, so I'm trying to create an If loop that will see if it is on the primary key column, but i'm unsure of how to do this. I tried doing this:
If dt.Columns(i).Unique = True Then t(i).Enabled = False End If
But this didn't work. I found an option called PrimaryKey which would go dt.PrimaryKey... something (I'm guessing) but just unsure of how to use it.
I'm using vb2005express for forms (front-end) and ms access database. I have a form with a master-detail setup. The problem I'm having is that when I set the primary key column to autonumber, I don't get the pk value generated in ms access database into my master datatable in forms when a new record is created. Then I tried setting the AutoIncreament to True in the pk column of the datatable in my dataset (forms). This generates a number in my pk column but its not the number generated in the database (since I think because the pk column is still set to AutoNumber). So I change the field property of my pk to Number in the access database and on my dataset (forms), i still have AutoIncrement to True.
This works okay since what it seems to be doing is getting the max value for the pk column when the datatable is filled upon form load. The problem now is that I normally don't do tableadapter.fill(datatable) at form load since I think there would be a performance issue if record counts around millions. What happens now is that when I create a new record, the pk generated is still 1 which will cause duplicate violation when saving to database. I'm not quite familiar with access features but in oracle, what I do is I create a sequence in database then I create a function that gets the next value of the sequence. Then at form load I set the datatable.column.default_value = get_sequence. How do I do this in ms access?
i am wondering if it is possible to get the source code for the following:
1. use vb.net code to set on/off primary key when connected to Access database
2. update a particular data.
for e.g: hostname: AES-19 *use source code to check data in Microsoft Access database if hostname is new, insert into Access. if hostname already exist, update into Access *so that i will not have duplicate data in Access.
How do I fetch the loginID and display the student data on the textbox?E.g. I login with loginID of 18 but it only display the data of 12
Private Sub frmLibrary_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load 'TODO: This line of code loads data into the 'LibraryDataSet.Student' table. You can move, or remove it, as needed. Me.StudentTableAdapter.Fill(Me.LibraryDataSet.Student) End Sub
I have managed to successfully create a logon page and have created a form to insert data into one of my tables using text boxes and a "Save" button, however the first field in the table is the named "CustomerID" and is set to Autonumber, this is the primary key of the table. If I enter a record into the table in Access it automatically enters the next valid ID however when I can't seem to make this happen when entering data via my VB form!
I am trying to append multiple rows in a SQL Server.I have connected to the MS SQL Server and with a DataAdapter, I have downloaded the Table into a DataTable and displayed it in DataGridView.I now want to programatically enter multiple rows into the DataTable and later to update the SQL Table.
I am trying to build an application to do this generically.The problem I have is that the Table and DataTable has an 'ID' Field. In the SQL DB, i is an Auto-incrementing field.When the code loops through creating new rows and entering field values, how do I handle the ID Field that is the Primary Key?
When I add a new row to an access database, I would like the primary key to be automatically incremented and entered. I've got this to work using a sql database, but it doesn't work with access for some reason. The following code works if I give the code a value for "@key" which is my primary key column. If I leave it out I get the error "Number of query values and destination fields are not the same". I don't want to have to supply the primary key, I want it to generate automatically.
[Code]...
In the database the primary key is type "AutoNumber". Does anyone know what I'm doing wrong?
How do I increment a primary key that is in integer digit format to a record when adding or pressing an "Add New" button that I have on my form. In other words, I have a 'Add New' Button that has the code following:
[code]...
As you can see from the above code, that most of the textboxes are cleared so that a enduser can insert his or her values and information. Currently, I do have the OrderNumber which is the primary key cleared, however, I would rather have this field auto incremented to the next digit. For some reason, at the moment, I just do not know where to begin to set this field so that a digit canbe inserted and incremented rather than cleared.
The first problem I have now is how to add all the data to the combobox from access 2007? [I have solved this myself accidentally.]
The second problem I have is I cannot save the primary key.
Assume that I have these: Table name: tCustomer Fields: ID Datatype [Text]
[Code]....
Now, the user fills in the form. The ID cannot be edited by them where it's automatically counts the number of customer in database and give the id. For example, I already have 3 customers in the database so when I add new Customer, it will be 4 for the ID.
When I click save, it shows me the message of "Index or primary key cannot contain a Null value." I have set an input mask for my Customer. So, can I make it to save in a format like CT001, CT002, CT003 automatically?
Lets say we have an Access file in a well known path (i.e. "C:MyFolderMyFile.mdb"). That file does not have a primary key set on the table we are interested in . Is it possible to set one of the fields as a primary key (for example the "ID" field , which is also an AutoNumber data) ? And one more thing : I'd like to change the name of a field on that table . For example , lets say there is a field called "My Field 1" (note the space characters) and we want it to be renamed as "My_Field_1" . If it's possible , I'd like both these changes to be permanent in the data base file itself , not just in the imported DataSet ,
(using VB2008) I am trying to automate Access from VB.Net. To do this, I added two libraries to my project, Microsoft.Office Interop.Access v12.0.0.0, and dao v10.0.4504.0. This seems to give me all the necessary commands, yet when I tried to open up an Access database via the following code:
