.net - Update Students Table Record Using LINQ To SQL?
Aug 22, 2011
I´m trying to update my Students table record using LINQ to SQL. The problem is when one of the Properties of the object changed and 'PropertyChanging' Event is fired using 'SendPropertyChanging()' method.
student_id is a PK
data types are matched
Here is the full ArgumentException:
GenericArguments[2], 'System.String', on
'System.Data.Linq.Mapping.PropertyAccessor+Accessor`3[T,V,V2]'
violates the constraint of type 'V2'.
am having a query regarding updating a table A records from table b on a button click...have created connection sting and commandtext to exexute d query am tryn ds query bt it seems to throw some syntax error
cmd.CommandText = "UPDATE stockno_table SET(product_id,Sold,Rec_No) =(SELECT product_id,Sold,Rec_No from stockno_temp_copy where stockno_temp_copy.stock_no=stockno_table.stock_no) where(exists)(stockno_table.stock_no=stockno_temp_copy.stock_no)"
basically the fields are same bt the stockno_temp_copy is a temporary table which i want to empty always while it updates all the table records to stockno_table...all the records except the Sold which is YES/NO field changes...NB: Access DB is used?
I have 2 tables Table1 with columns [BId,Name,Amount] Table2 with columns [CId,BId, ExpenseType,Expense]. BId Is the foreign key in Table2. The Amount field in Table1 is always higher than Expense in Table2. I need to update the values of Amount (increase or decrease) based on value of Expense and I want to do it in single query in LINQ. Eg If the Expense has to be updated with 200, I would decrease(negate) Amount value with 200. If Expense is reduce to 100 then the Amount is increased by a value of 100.
I have a process that is a detail/Master issue. I read (into a dataset) my detail record based on several keys. Then I have to read each master record..check some fields/update some fields and then update that master. Detail is not changed. First.. How do I not lock the detail table during my select?
I want to update a date field in my table when a record is updated to reflect when the last update was made. I have this for the parameter: objEXTCommand.Parameters.AddWithValue("@entryDate", Now.Date)
However, this inserts the Date and a time of "12:00:00". I want the date and current system time. I've gone about several ways, but none seem to work. I try this: [Code]
how to edit and update in relational table's record in visual basic 2010?
have two tables with Relationship
1, Orders
2, Order_Details
"Orders" Related with "Order_Details" ( OrderID )
now i want to Edit and update. Record in "Order_Details" ( "Pencil" to "Pencils" ) Then Update changes
my code is below
Dim CurOrder_DetailsRow As OrdersDataSet.Order_DetailsRow CurOrder_DetailsRow = CType(CType(Me.Order_DetailsBindingSource.Current, DataRowView).Row, OrdersDataSet.Order_DetailsRow)
I am working on an application for Point of Sale system in .Net 2008,vb with MsAccess as database and now i am on the final part of this application which is inventory module. Where in that module i have created Stock table and I have two tables related to stock.
I am leaning VB and have created a basic inventory app for work that consist of 4 tables, CurrentInventory, Surplus, Staff and Category. Each of these tables have a corresponding form. My question is with the CurrentInventory and Surplus form/tables. I want a button on the CurrentInventory Form that when clicked the current record would be transferred to the Surplus table and deleted from the CurrentInventory table.I am assuming that I could somehow use the INSERT command to copy the current record to the surplus table but I am not sure how to accomplish this.
I am handling many of the BindingNavigator tasks (MoveFirst, MoveNext, etc.)in code to ensure that I always ask the User to save his changes.
The one area I am have a problem is PositionItem. I would like to sense that the User has changed the Record Number in the BindingNavigatorPositionItem, handle my record Update, and move to the Record Number the User entered I have looked all over and have not found any way to do this.
I have two tables Products and Categories with a many to many relationship. I am trying to copy the categories linked to one product (OriginalProduct) to another product (newProduct). The problem is when I execute the SaveChanges() method, I not only get the records in my linking table, but it also creates another copy of the categories in the categories table. I've tried this in many ways but here are the last couple that I've attempted:
' Copy Product/Categories For Each oneProdCategory In OriginalProduct.Categories Dim relatedCategory = _productContext.GetObjectByKey(New EntityKey ("ProductInfoEntities.Categories", "RecordId", oneProdCategory.RecordId))
i have gridview 1 and textbox1 and button1 i want when pages load the gridview displays the all records from table1 and also ...i i wanna search record for firstname by typing sumit in textbox1 and click on button1 then in gridview the record of sumit will be shown ..by default gridview display alll records from table1 How to do this My Selct Query is below : but it doesnot display all record ...but it can display record if you search for a particular record .
I'm receiving the following error:"You cannot add or change a record because a related record is required in table 'FORN_NIB'."
I cannot understand this error fr the related record really existe on the FORN_NIB table. It is even picked up from there. Here's the code where the error occurs at the .Update instruction:
HTML With rst .Open("DADOS_RECIBOS", conn, ADODB.CursorTypeEnum.adOpenDynamic, ADODB.LockTypeEnum.adLockOptimistic) .AddNew() .Fields("NUM_FORN").Value = Me.TextBox1.Text
Public Sub UpdateStaff(ByVal sr As StaffRecord) Dim oldSr As StaffRecord Dim q = From staff In db.StaffRecords Where staff.Employee_Number = sr.Employee_Number Select staff oldSr = q.First oldSr.Address_Line1 = sr.Address_Line1
[Code]...
The helper function I have written seems to do everything I want apart from update the db. Stepping through the code, the oldSr is updated by the new sr parameter but no update on submit changes.
I have two tables Employees and CafeLogs. Some employees can be cashiers and also customers at the Cafe shop.
Table structures:
Employees: EmployeeId(PK) , FirstName, LastName CafeLogs: LogId (PK), CashierId, EmployeeId, Value, => CashierId and EmployeeId are the data from column EmployeeId of Empoyee table
Table relationship:
Employees 1:N CafeLogs (CashierId (FK))
[code]....
Right now I know how to select only LogId, Employee's name, and , Value, not with Cashier name yet.
Dim query = From log In db.CafeLogs _ Join emp In db.Employees On emp.EmployeeId Equals log.EmployeeId _ Select log.LogId, emp.FirsName, emp.LastName, log.Value
I have this code to edit the datarow of my table adapter but t doesnt update the table. I think i have a missing code that's why but i cant figured it out. by the way im using vb2008 and SQL as my database. [code]
I have a project which contains a large number of lookup tables, and I have all of these lookup tables represented in a single typed DataSet, which contains TableAdapters for each lookup. I've designed an editor for these lookup tables, which should allow editing of one of these at a time. My front-end is written in VB and WinForms, the back-end is a SOAP web service; I can successfully pass the changes to the DataSet back to the web service, but can't find a way to use a TableAdapter to update the single table that has been changed.
What I'm trying to do is instantiate the appropriate TableAdapter for the updated DataTable by sending the name of the table back to the web service along with the DataSet, then referring to the TableAdapter with a dynamic name. The normal way to instantiate a TableAdapter is this:
Dim ta As New dsLookupsTableAdapters.tlkpMyTableTableAdapter
What I'd like to do is this, but of course it doesn't work:
strTableName = "tlkpMyTable" Dim ta As New dsLookupsTableAdapters(strTableName & "TableAdapter")
Is there any way to achieve this, or am I taking the wrong approach altogether? My other alternative is to write separate code for each table, which I'd prefer to avoid!
An unhandled exception of type 'System.InvalidOperationException' occurred in system.windows.forms.dllerror in line: dbAdp.Update(dbDset) in btnSave_Click, (elseif editflag = true) blockdescription: Update unable to find TableMapping['Table'] or DataTable 'Table'I was also wondering if I could simply use the ExecuteNonQuery for the delete statement, but since I've placed my data in a datarow, I'm not sure if i can actually use it. Any thoughts on this? Btw, this is my first time using a datarow, and I've recently been studying how to use ADO.net.
dr = dbDset.Tables(0).Rows(CurIndex) dr.Delete() dbAdp.Update(dbDset.Tables("addresses"))
I have been utilizing Scott Gu's tutorials on LINQ to SQL to try to learn some LINQ. I have been able to view, retrieve, and update records but I am unable to write new records into the database (MSSQL). Scott starts getting into inserting rows in the fourth section of the set of tutorials. As you can see on that page (or may already know), in order to add a record you must do the following (VB.NET)[code]...
I am trying to insert a new record though linq. I am able to update and read data with out any problem, but how to just inset a new record. Here is a start of my function.
Public Function AddAddressInfo(ByVal objdeptGUID As String, ByVal objGEOCode As String, ByVal objArressCommonName As String, ByVal objStreetAddress As String, ByVal objAddressNotes As String, ByVal objIsPublic As Boolean, ByVal objSesionToken As String) ''#Check of Token is good If CheckToken(objSesionToken, objdeptGUID) = False Then Return "Error" End If [Code] .....
How can I update local dataset with mysql database without making duplicates. Assuming I set some column in mysql as primary key, which has unique string.
adapter.fill will just add duplicates, but adapter.clear before that is not an option.
So I want to update if the key column is the same with mysql data and if there is option for ignore adding new row.
i have some sample code on inserting a record from one table to another new table? Making the record on the first table to be deleted and been transfered to another table ..