I'm playing around with Linq and XML and came across a need to update an XML node. Below is my code to read the xml, my question is, can I edit the xml source that I have loaded in to memory (from file) and save it?[cod]e...
View 1 RepliesPublic 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.
Im trying to update the "value" Attribute of some xml file that have this structure:
<app-settings>
<setting name="codeBasePath" value="E:data" />
<setting name="server" value="LOCALHOST" />
[Code].....
discovered the compact mode of this instructions vs usual code. I found sample code for selecting, etc. from a datatable, transforming a column in a list or array - all operations are "Select"s - readonly.I need to make an simple update on a certain rows (using LINQ) from a DISCONNECTED datatable for which now I'm using this
for each dr as datarow in dtable.Rows
dr("MyField") = 77
next
[code].....
I need to update a datatable using LINQToSql. Option Strict is ON. Datatable name is Customer with fields customerID, customerName, SalesID. I need to update rows with SalesID = -1.
View 1 RepliesI'm editing XML element with the following XML:
<?xml version="1.0" encoding="utf-8"?>
<!--Test XML with LINQ to XML-->
<LabSerivceInfo><LabService>
<ServiceType>Copy</ServiceType>
<Price>1</Price></LabService>
[Code] .....
How to update the ServiceType and Price where ServiceType = varServiceType?
I am a bit new to linq, I am only using linq for filtering the data. [code]...
Con.Numbers is a dictionary, but now I converted it into a list, hence the above code wont work with list[code]....
I'm trying to update an element in the XML document below:
Here's the code:
Dim xmldoc As XDocument = XDocument.Load(theXMLSource1)
Dim ql As XElement = (From ls In xmldoc.Elements("LabService") _
Where CType(ls.Element("ServiceType"), String).Equals("Scan") _
[code]....
But, I got this error message:
Object reference not set to an instance of an object.Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.Error line:ql.SetValue("23")
In general I have a xml document that i need to update.The query looks like this:
Of course it gives me a "This attribute is readonly" error.[code]...
Very simple update. It simply fails, no error, no change gets made to the database.Dim db As New BarClassesDataContext Dim foo = (From a In db.articles Where a.id = 14 Select a).Single Response.Write("<h3>" & foo.title & "</h3>") foo.title = "This is my new, updated title for article ID #14"
db.SubmitChanges()
Here is the relevent portion of my article class. Also, this is a web form so I have no console. Is there another way to view the T-SQL output?
<Table(Name:="dbo.article")> _
Partial Public Class article
Private _id As Integer
Private _issueid As Integer
Private _dateadded As Date
[Code]...
im pretty much a beginner to using ASP.net and linq to sql but what im trying to do is update a column of a table based on a variable. at the momment i have
Dim db As New sqldcDataContext Dim update As tableName = (From i in db.tableNames _ Select i)
i think this selects everything, how could i have two variables, one to store what table to update and the other what column. is this possible?edit: sorry for being unclear im trying to make this as dynamic as possible so i dont have to type in the exact table/col names. something like this but in the linq to sql syntax.
mysql_query("SELECT * FROM ". $table ." WHERE `" . $column . "` = "" . $data ."");
I use the following statement to position which row to update;
Dim salonToUpdate = (From r In db.Salons _
Where r.StoreID = storeID _
Select r).Single()
If fileDate = #1/1/1900# OrElse fileDate = Nothing Then
SalonToUpdate.LastDownLoadDate = TableDate
[Code] .....
I've double checked to make sure none of the dates are invalid or null, but when the bolded statement executes, the following sql runs through the trace:
exec sp_executesql N'UPDATE [dbo].[Salons]
SET [LastDownLoadDate] = @p0
WHERE 0 = 1',N'@p0 datetime',@p0='2008-01-04 00:00:00:000'
Of course it's going to fail if LINQ is passing in where 0=1 every time. Shouldn't it be using some unique row identifier, (in my case, the salon id), to update the specific row?
I am using database compact and i loaded it on my form and i want to update a single field but I cannot, why:
what am doing is:
dim newrec as datatable=(studentdataset."TableName")
dim querie= from det in newrec.asnumerable() _
[code].....
I use this command to retrieve information from an Access database:
Try
Dim result = From row In Me.ChitaDataSet1.chita.AsEnumerable() _
Where row.Field(Of String)("askID") = x _
Select row[code]....
how to Update a cell in specified row-coloumn coordinates?
Im using linq and im able get get data ouf of it realy easy. but i seem to not be able to update the data. the program does not error on it and it looks likes it has updated but it does not save te changes.
Public Function UpdateAlarmsbyKey(ByVal objKey As Integer, ByVal IdNumber As String) As Boolean
[Code]...
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.
View 1 RepliesI´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'.
[code]....
I am pretty new to using LINQ and have been trying it out querying my strongly typed DataTable.
I have managed to perform a 'Select' ok but was wondering if someone can point me in the right direction to do Insert and Updates. I'm not sure if LINQ is best doing an insert at all?
My Select code is as follows:
Dim results = From myRow In _dt.AsEnumerable() _
Where myRow.Language_key = Lang And _
myRow.Section_key = SectionKey And _
[Code]....
[code]How do I update the ProdServiceID in the database using LINQ to entities?
View 1 RepliesHow to update columns in datatable using linq without conditions. I have an idea that I'm just gonna loop all the data in the datatable but don't know what comes in LINQ.
View 5 RepliesI have a page with a form on it and needs a range of dates. Thus I've placed a number of textboxes on the page into which users can type dates. When the user clicks the save button I want to trigger a LINQ update to the SQL Server...all the rows already exist, so I'm just updating existing data.
For example, lets say my table looks like this:
Column Names: Description dateValue
Column Values:
Birthdate 1/1/1990
Anniversary 1/10/1992
Death 1/1/1993
I want to do something like this:
hupdate.Description("Birthdate").dateValue = TextBox1.Text
hupdate.Description("Anniversary").dateValue = TextBox2.Text
hupdate.Description("Death").dateValue = TextBox3.Text
hconfig.SubmitChanges()
Is there a way to do this with LINQ?
I'm using visual basic 2008 express edition by linq to sql for my database operation such as edit records. I did not use any sql server but I'm just using the built-in sql server within the visual basic 2008 express. I tried to revised the codes, no error in syntax but there's an error at runtime and it pops-up a window message saying its error message. What I want is to edit the records which were retrieved from the database into the text-boxes and when you click the button5 whatever the new value on the text-boxes should replace the previous one.The Account field is the field in my Table1 in memrec.dbml which I set up for primary key is true and the rest of the fields are false in its primary key.[code]...
View 3 RepliesI'm using visual basic 2008 express edition by linq to sql for my database operation such as edit records. I did not use any sql server but I'm just using the built-in sql server within the visual basic 2008 express. I tried to revised the codes, no error in syntax but there's an error at runtime and it pops-up a window message saying its error message. What I want is to edit the records which were retrieved from the database into the text-boxes and when you click the button5 whatever the new value on the text-boxes should replace the previous one.The Account field is the field in my Table1 in memrec.dbml which I set up for primary key is true and the rest of the fields are false in its primary key.The code below still found an error when you run the program and it pops-up a window which says:
NotSupportedException was unhandled - Sql server does not handle comparison of NText, Text, Xml, or Image data types.It highlights a yellow background on the line:
db.SubmitChanges()
These are what I see on each field's property on Table1 in memrec.dbml property window:
Access - Public
Type - String(System.String)
Server Data Type - Text[code]........
I'm looking for a simple example in VB2008 code.I have the Northwind DB installed on one of our SQL servers.
I've worked with the Datagridview on serveral occasions but never used its update,delete or add functions. I've Googled around the web, but could not find a simple example.
Whats the best way to do this and implement it using LINQ?
I have the following LINQ-to-Entities query:[code]This will give me all the resident assignments for the current year/term. Then I have this LINQ-to-Entities query:[code]This will give me all the rooms. I want to iterate through the assignments and based on what room is assigned update the occupancy in reset_occupancy. I'm not 100% sure how to accomplish this. Here is my pseudo code of what I want to accomplish:[code]
View 1 RepliesI have the following LINQ-to-Entities query:
' Get all the residency assignments that match the term/year.
Dim assignments = From p In dbContext.Residents _
Where p.semester = term _
[code].....
This is the hardest part of LinqtoSql database handling operations in visual basic 2008 I ever encountered,w/c is the update operation cause Ive been posting this thread several times from the other forum site but noone yet was able to answer my question,examples were given but its not efficient cause it won't specify based on the codes i gave and i know its not easy but im still hoping that one of the answerers of this forum will be able to resolve this particular linqtosql operation codes. I used textboxes in manipulating all data into the database such as displaying records, adding records, & updating records, basically I used with textboxes in doing those database operations. I will give you 3 block of codes w/c corresponds those database operations I used and differentiate from each other inorder for us to determine why one of them has no progress or won't do its operation w/c is the update operation...
*************Block of Codes#1(Adding Records)*************
Private Sub Button1_Click(------------------) Handles Button1.Click
Dim db As New memrecDataContext()
[code]....
I would like you to identify,differentiate, or troubleshoot the block of codes#3, or anyhow, why it has no progress at all or it won't edit and change the records but it runs and no error in regards with its code, and the other 2 blocks of codes were able to successfully do its operations.I was just wandering why only the block of codes#3 is not doing its operation successfully when you change the record being displayed in the textbox.Is there a possible way to edit records in the textboxes?If there is.... Is it possible to debug the block of codes#3 to successsfully do its operation? If you could possibly give an example,can you based it on the block of codes#3?
just want to know if linq to sql auto updated the id column of a class (table row object) after SubmitChanges is called inserting a new row to that table, that would be fantastic, would anyone be able to confirm this?
View 2 Repliesgiven this function:
Public Function Search(ByVal StartIndex As Integer, _
ByVal MaxResults As Integer, _
ByVal AccountNumber As String, _
ByVal LastName As String, _
[Code]....
instead of what I expected:
Select count(*) from remitline where lastname = "smith"
What am I doing wrong building up the where clause? I'm using Castle ActiveRecord 2.1
if there is that much of a performance gain in running a LINQ stored procedure versus a LINQ query?
View 1 Replies