DataSource Controls :: Passing Null To Storedprocedure Using Linq
Mar 31, 2010
I have a SP db.sp_GetProfitMatrix , it takes nullable integer parameters, for which I have a default . It refuses me when I try to pass a null value (the two date parameters are nullable in the Linq designer) I get {"Nullable object must have a value."} error. here is my code:
int? nlDt = null;
var pms =
from p
in db.sp_GetProfitMatrix( nlDt.Value, nlDt.Value)
select
new
{
p.Volume,
p.GrossSales,
p.NetSales,
p.COGS
};
I have req where i have to pass null value,if value coming from db is null.Problem here is the field datatype is 'Decimal' so all the time even though value is null ,its passing as zero.How can I pass a null value to decimal field in C#.
I have req where i have to check the value coming from db is null or not and assign value according to that.Problem here is the field datatype is 'Datetime' so all the time when I tried to use the below line of code its giving me error.How can I pass a null value to datetimefield if value coming from db is null.
im new to linq and im having lots of trouble creating complex queries.. My problem mainly is that i am using Linq as a BLL.
i created a dbml (with namespace called DAL) file with 2 tables with a one to many relation. Pop and City. There is a forgien key in pop that points to a city. I also created a class called Pop that inhertis DAL.Pop. Now in my ASPX page, i want to call a function in the Pop class that would retrieve some Pop according to its ID, but i need the city name as well.. Ive been going around this in circles for days. I dont know how to write the Linq syntax and i dont understandd how my function's signature should be like.. I want to recieve a table that i can bind to a Gridview and preferable, specify which coloumns to bind.
I am using ASP.NET 2.0 and C#, SQL Server 2005. I am passing parameter to a stored procedure. The parameter is the ProductId. I have 3 types of productId. ProductId 11,0,12.
If the ProductId is zero, I want to pass the productId as 11 to the parameter.
need a Stored Procedure with a where with 23 where items.But if a item is 0 then i should skip that selection.So i need something like the code below, but sadly that doesnt work... And 23x23=529 selections isn't a option for me.
I am going to insert Multiple record IN sql using storedProcedure from gridview...
for this purpose i am using cell concatinating method and send whole gridview cell data in string variable.
i have tried xml document method or sending data in table through looping as well but didn't satisfy from both of them... b/c concatinating method required a delimeter for seperation(for which i have restrict the user from that sepereator ) and xml method required an extra file which is not a efficient approach .
I have a CheckBoxList that I need to get the values from, concatenate, and pass into a stored procedure in SQL Server 2005 utilizing Visual Basic. Due to the way our data layer is I cannot use a SqlCommand object at this level.
I have no problem getting to the selected values in the CheckBoxList:
Dim selectedValue As New StringBuilder For i = 0 To cblMethods.Items.Count -1 If cblMethods.Items(i).Selected Then selectedValue.Append(cblMethods.Items(i).Text) End If Next
The problem is that I do not know how to list the values in such a way that my stored procedure will pull data:
SET @MethodNames ='GetWords','GetLetters' SELECT * FROM TABLE WHERE method IN ( @MethodNames ) I've tried experimenting with apostraphes but cannot make it work: selectedValue.Append("'''" + cblMethods.Items(i).Text + "''', "
This is an ASP.NET 3.5 web app written in C# using VS2008 and connecting to an MS SQL backend. It is using ad hoc queries in a strongly typed dataset to pull from the database. This query (shortened for clarity) is designed to allow optional input of parameters (a requirement) or pull all records if no parameters are input. It works normally in SQL Server Management Studio with the addition of Declare and Set statements and it works normally in the TableAdapter's Query Builder:
[Code]....
The markup contains this ObjectDataSource, which is tied to the TableAdapter with the above query:
[Code]....
The problem I'm having is in passing null values to the ODS to feed to the query. Tying the ODS parameters directly to the dropdownlists and textboxes didn't work. Got an error message that there was a mismatched data type. Tried several combinations of code to feed the right values to the ODS parameters but couldn't find one that worked. Is the problem in the query or am I setting up the code-behind wrong? Here's the code:
I am writing a plugin to help with a current ERP system we have that I am not allowed to modify the data structure at all. The table I am dealing with has over 100 columns and I am wanting to set my linq object propertychanged event and submitchanges or do I really have list out each property and set it equal to the new one?Below is an example of what I am trying to do:
Like that I have large number of controls on my form. I have dought, if I assigned like this, db.usp_ATI_FetchPatientDetails(iPatientID).ElementAt(0).Last_Name.ToString(); to every control, then I have set of controls like,
My question is that, for each control the Stored Procedure called or not? If it is yes then it is time consuming and I need to use LINQ to DataSet or LINQ to Object rather than to call SP for each control. What is difference between LINQ to DataSet and LINQ to Object?
here is my code for selectiong some records from db table
string strSql = "select * from mtblNBD where SentTo=@SentTo and InternalStatus Is NULL order by DeadLine desc"; SqlCommand com = new SqlCommand(strSql, con); com.Parameters.Add("@SentTo", SqlDbType.NVarChar, 50).Value = (string)Session["uname"];
here I am using parameters for SenTo field but not for NULL so it is ok... or should I use parameters for this field where value is NULL , if yes then how can I use parameter for this
I have page that has a datasource. The datasource executes a stored procedure and returns results. If the result is NULL, I'd like to forward the user to an error page. How would I accomplish this with ASP.NET and C#?
public IEnumerable<Customer> GetCustomers() { Table<Customer> custObject = context.Customers; IEnumerable<Customer> filteredCustList = from customer in custObject select customer; filteredCustList; } GridView2.DataSource = utilLinqClass.GetCustomers(); GridView2.DataBind();
(no errors at build time or at compile time) Error I am getting is: An attempt to attach an auto-named database for file App_Dataaspnetdb.mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share.
Passing onto a stored procedure a value from a GridView. The particular fields are a date type, and numeric type. Problem is, its plausible and conceivable in this case one or both could be null or empty.
Through searching I've seen suggested such ideas as Convert.ToDate(value), CDate(value), and so on. None of these work. You cannot convert an empty string or null value to a date. I don't know about the numeric value.
So, barring any non-working examples already given. What is standard. Its not like I've stumbled across some never afore seen problem.
Here is my code, but its quite typical.
Dim txtctlHireDate As TextBox = CType(gvEvaluatees.Rows(e.RowIndex).FindControl("txtHireDate"), TextBox) Dim txtctlGradYear As TextBox = CType(gvEvaluatees.Rows(e.RowIndex).FindControl("txtGradYear"), TextBox) Dim txtctlBU As TextBox = CType(gvEvaluatees.Rows(e.RowIndex).FindControl("txtBU"), TextBox) Dim ddlctlEvalGroups As DropDownList = CType(gvEvaluatees.Rows(e.RowIndex).FindControl("ddlEvalGroupSelection"), DropDownList) Dim chkctlActive As CheckBox = CType(gvEvaluatees.Rows(e.RowIndex).FindControl("chkActive"), CheckBox) UpdateEvaluatees.MGEvalUpdateEvaluatee(gvEvaluatees.DataKeys(0).Value, txtctlHireDate.Text, txtctlGradYear.Text, txtctlBU.Text,ddlctlEvalGroups.SelectedValue, chkctlActive.Checked) gvEvaluatees.EditIndex = -1 gvEvaluatees.DataSource = EvaluateesForDataGrid.GetData gvEvaluatees.DataBind()
I've bolded the parameters in question. A date value and numeric value are expected.
