I'm trying to define a computed column that will contain an auto-incremented number. In other words, I want it to work exactly like identity, but since I can have only one identity column per table, I wanted to make a computed column that reads its latest value and increment it by 1.
View 5 RepliesHow do add read-only computed column in LinqToSql designer (dbml)? My existing table structure:
Name: ID, Type: int, AutoGenerate: true, AutoSync: OnInsert, PrimaryKey:
true, ServerDataType: int not null identity, Source: IDName: Name, Type: string, ServerDataType: nvarchar(100) not null, Source:
NameName: Value, Type: byte[], ServerDataType: VarBinary(max), Source:
Value, UpdateCheck: Never
I want add the 4th colum name: Name: HasValue, Type: bool --> [Value] != null
How do i generate another computed column that will contail the result of GrandTotal/Total,
where GrandTotal is another value comes from computed column and the Total would be the sum of the Total within SchedularID.
And thats what i have done so far: [Code]....
I have a simple list of data in my database that I call to my page. I have used the asp.net 'reorder list' ajax control to provide a drag and drop way of managing the sort order of my data. It uses a 'position' column in the database to do this.
How do I go about making sure that when inserting data to this table, the new item gets assigned the correct 'position' value? For example if I have 9 items already in my table, I want this newly inserted list item to get assigned a value of 10 in the position column.
How do I select a column with the latest "datetime" data type, in Visual Web Developer 2008, ASP.NET 3.5 ?
In the config data source WHERE option my options are greater than cookie, control, etc... but I would like to select where the datetime is the latest in the table.
I have a datatable in MS SQL that has FirstName and LastName. In MS SQL I created a computed field called FullName that was ((rtrim([LastName])+', ')+rtrim([FirstName])) I created a DataSet and a Business Logic Layer. In my typed DataSet I saw FullName in the listing when I created it. I am able to use FullName in my webpage. I use it to populate a dropdownlist. However, now when I make changes to the Customer Table I am getting this error message (seen below)
Question: Should I have created the field FullName in my MS SQL Table or should I have left it alone and somehow just added a column to the DataSet and placed an expression in the FullName column? The column "FullName" cannot be modified because it is either a computed column or is the result of a UNION operator. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Data.SqlClient.SqlException: The column "FullName" cannot be modified because it is either a computed column or is the result of a UNION operator. Source Error:
[Code]....
Source File: c:Users ottfarmsAppDataLocalTempTemporary ASP.NET Filesinternalauburnriverside98ea0e1f2a7f0720App_Code.lbdcba1v.2.cs Line: 1240 Stack Trace:
[Code]....
I have stumbled into a problem in which Im having a hard time solving. I have a linq data setup(based on a mssql) where a Purchase Order contains a number Equipments - each equipment has a price. I have a gridview that shows the summed price of the equipments that are included in a Purchase Order. This sum is currently being calculated on RowDataBound through a "listOfEq.Sum(Eq => Eq.PurchaseOrderPrice);" expression which works without any problems. My problem is that I want to be able to sort the gridview based on this summed value, which I cannot do with a normal sortexpression. My next thought was to create a function in my database to calculate the sum instead and then use this is my data basis for the summed column. I have created a function like this:
[Code]....
I want to create a sortable column based on this data. My thought is something like this:
[Code]....
Displaying the correct information is not a problem, however creating the sorting is. Im not sure what to put in the SortExpression. Anybody got an idea of what to do? Perhaps I am forced to use a computed column for this however I dont know to create this column when its based on another table. If this is the case, any idea about how to do create a computed column thats based on data from another table?
I have couple of DDL's which let user choose couple of different values from it. Once the user has made his selection he clicks on the "Submit" buttion which redirects the user to the other page, which then displays table from backend SQL DB. The pages are named Page1.aspx and Page2.aspx resp. I am using Querystring to carry forward the values of the DDL's to Page2.aspx.
How can i modify the query in such a way that even if one of the DDL's is left blank the Query would ignore that and shall produce the table considering value of DDL2 in the where clause. In case both the DDL's are empty then the query will not have a where clause and shall showcase the complete table as such. I've written a query for this but it's not working the way it shoul.Here is my code for the SQLDataSource: [Code]....
I have the following GridView:
<asp:GridView ID="gv" AutoGenerateColumns="false" runat="server">
<Columns>
<asp:BoundField DataField="productName" HeaderText="Item" />
<asp:BoundField DataField="unitCost" HeaderText="Cost" DataFormatString="{0:c}" />
<asp:BoundField DataField="originalCount" ItemStyle-HorizontalAlign="Center" HeaderText="Old Count" />
<asp:TemplateField HeaderText="New Count" ItemStyle-HorizontalAlign="Center" >
<ItemTemplate>
<asp:TextBox ID="NewCount" Width="20" runat="server" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
And I want to add a final 'Total' column that calculates (originalCount - NewCount) * unitCost and updates it as the user enters a number in the NewCount text box. Can I do this just with .net, or do I need to use Java? If the latter, how do I tell which Gridview cell to update?
I have a column that contain date (of type datetime), i also want to add another column that will contain 1 Or 0 depends if the value of date has passed the current date or not.
View 4 RepliesAfter looking for a driver to open legacy dbf drivers to connect, the next level trouble a have is this one: first, i can retrieve the data but when trying to filter by a parameter (somesc columns) i get an error. The error says about the database can't determine. The error is a columm tha is formated ( 1234 ) about 8 space, fixed. The values in the query appears like that. I resolve this by Trimming Ltrim(ColumnName) and i get this (1234). Now in SqlExpress, how can i filter by the new Trimmed Expression? (This is a primary key that the DBF use)
Sample:
SELECT column1, column2, column3
TABLE FoxProDB
Now
SELECT Ltrim(column1) as NewExp, column2, column3
TABLE FoxProDB
Where NewExpre = @NewExpres -Error-
Using vs2008 I have a SQL Server database attached to my web app. I want to use a computed time column in the database, along the lines of :
timenow is 1 column
hoursleft is another column
timeend would be another column.
I want timeend to = timenow + hoursleft. Is it possible to do that, and if so what would the formula be that I would enter into the computed column field, and, what datatype would the columns be, timenow and timeend I would expect to be time(7) and hoursleft an int. But is that correct?
i have a ListView of items like this:
[Label] [Increment Button][Label] [Increment Button][Label] [Increment Button]... my question is how can increment the label when the button is clicked? i need to know, that the first button is clicked so i increment the first label. but how?
I have a table of people with columns holding bits of info about them. I also need a variety of computed columns such as FileAs (lastname + ", " + firstname) and CityStateZip (you get the idea). I am wondering where best to put these definitions. It's worthwhile to note that the user will want to search for things as seen on the page, not the little atoms in the table. For example, searching on ", e" finds everyone whose first name begins with E. Typing ", az" to get everyone who lives in Arizona.
I noticed that linq-to-sql queries only recognize the fields in the table definitions, not any that are added in the partial class associated with the dbml. Linq-to-sql does work against computed columns in the database; however, the column definitions--especially for international address formats--will become very complex and much better handled in code.
I want to create a computed column in SQL SERVER and set the formula to this
([Category] + '.aspx?ID=' + [Post_ID])
Not working though......what am i missing? Category and Post_ID are current columns in the table
i have designed a database into the vs 2008 mobile database. my batabase has three column column1(int),column2(int),column3(int) and i want to set the value of val(column3)=val(column1)+val(column2); how and where to set the computed column value.
View 2 RepliesI receive lists from a web service and then I convert the lists to datatable and then I add the datatables to a dataset and from there I get the xml from the dataset where I can save it into a sql database. But the problem is that the xml has /r/n between all attributes and elements. I dont know how to get this out of the xml. Can this be because of my converter. If so can anyone give me a better way to get multiple lists into a dataset.
View 2 Repliesi have a question, suppose i have a table 'tblImage' which have 3 rows of data and my auto increment is not +1.
imageId imageName
1 a.gif
2 b.gif
4 c.gif
i want to query '2' using LINQ C# to the table in MS SQL and show the record which i have done easily BUT now i want to get the next auto incremented value to make Next button on the sane web form, which is in this case is '4' and i also want the previous imageId as well.
I'm still relatively new to asp.net I'm trying to figure out the best way to write and implement this.
I have a cell that needs to autoincrement by 1 for every new database row in my table, Unfortunately I have to have the autoincrement restart at 1 at the beginning of each year so I can't use SQL Server identity increment. Maybe i'm wrong about the last statement and I just don't know how to do it.
The code i have is something like this:
If thereadedyear <> Now.Year then
theReadedYear = Now.Year
SomehowWrite readedYear
StartNumber = 1
Else
StartNumber =+ 1
End if
How do I implement this in a Insert Template?
i have a topic like this before and it has been resolved using dataread. But now, I want to ask on how to do it via dataset.
My code is:
[Code]....
What I want is to read the from the dataset the maximum value so there will be no need to open a connection from the database.
I'm trying to get an IDENTITY column to auto-increment with each new row inserted, so that the field (userid in this case) can be used as a unique identifier.
However, I'm getting this error:
[Code]....
My code looks like this:
[Code]....
I don't understand - if I have to explicitly insert something into my auto-increment column, how do I know what to insert? Isn't the point of an auto-increment column that it's... auto?
I am using LINQ to store and retrieve data from tables with a clustered index key. However, I also need to know how to obtain an inserted table row identity with an auto-increment Primary key. The "Go To Definition" feature for my data context of dataClassesDataContext provides the following information:
[System.Data.Linq.Mapping.DatabaseAttribute(Name="EFMDB")]
public partial class DataClassesDataContext : System.Data.Linq.DataContext
I am asking for the C# code that is needed in a button click event handler that will insert a row of data in a table named "Fields". It only consists of an auto-incrementing primary key column (FieldID), a string column (Phrase) and a null defaulted variable column.
show me what is the syntax to add an increment column to Select Query? There will be additional column which goes 1,2,3 ... n.
View 3 RepliesNo sense in showing a competely blank column. how to make a GridView column invisible if every cell in that column is empty?
View 3 RepliesHow do I select a column with the latest "datetime" data type, in Visual Web Developer 2008, ASP.NET 3.5? In the config data source dialog my WHERE options are greater than cookie, control, etc... but I would like to select where the datetime is the latest in the table. (Select row from table where datetime is last updated....)
EDIT - This will be for a specific user in the table, i.e. Select row in table from specific current userid WHERE the row was his latest updated entry.