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Problem in reteriving data from database

While retreiving data from database , i'm checking 3 conditions together, but the data is not getting displayed in gridview...

 protected void Page_Load(object sender, EventArgs e)
        {
            GetResults();
        }

        private void GetResults()
        {

            SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["HousingConnectionString"].ConnectionString);
            conn.Open();
            string query;
            SqlCommand com;
            SqlDataReader reader;

            SqlDataAdapter adapter = new SqlDataAdapter();



            query = "SELECT Flat ,First_Name , Middle_Name , Last_Name , Mobile_No , Email, DOB , Age , Education ,  Office_Add , Native_Add , PAN_Card , Aadhar_Card , Religion , Business_Job , Married_Unmarried ,  No_Of_Members , Joining_Date ,Leaving_Date from Ex_Primary_Member where Flat='" + Request.QueryString["fnum"] + "' and Joining_Date='" + Request.QueryString["jdate"] + "'  and Leaving_Date='" + Request.QueryString["ldate"] + "'";

            com = new SqlCommand(query, conn);
            adapter.SelectCommand = new SqlCommand(query, conn);

            reader = com.ExecuteReader();

            GridView1.DataSource = reader;


            GridView1.DataBind();

        }

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PortletPaul

You are selecting by date(s) is it possible that the precision of the stored data is higher then the precision of the parameters?

e.g.
if a stored date includes time like this 2015:10:10 12:13:14.12345
then
2015-10-10 12:13:14.12345 <> 2015-10-10

What happens if you omit the 2 date filters?

just for reference:

SELECT
      Flat
    , First_Name
    , Middle_Name
    , Last_Name
    , Mobile_No
    , Email
    , DOB
    , Age
    , Education
    , Office_Add
    , Native_Add
    , PAN_Card
    , Aadhar_Card
    , Religion
    , Business_Job
    , Married_Unmarried
    , No_Of_Members
    , Joining_Date
    , Leaving_Date
FROM Ex_Primary_Member
--where Flat='" + Request.QueryString["fnum"] + "' 
--and Joining_Date='" + Request.QueryString["jdate"] + "'  
--and Leaving_Date='" + Request.QueryString["ldate"] + "'";

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Paul Jackson

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DcpKing

Pick 3 common values that you expect to give a result and run the query straight on the database (in a query window in SSMS). Do you get the expected results? (yes, I _know_ that seems a silly question, but you wouldn't believe how often one writes code and testing fails ... because the right data isn't present!)

Try putting the query into a stored procedure and invoking that from your ASP instead of a direct query.

In T-SQL that would be

create procedure MyTest
(
    @intFlatNum   int,
    @daJoiningDate   date,
    @daLeavingDate    date
)
as
Begin
    set nocount on
    SELECT Flat ,First_Name , Middle_Name , Last_Name , Mobile_No , Email, DOB , Age , Education ,  
                  Office_Add , Native_Add , PAN_Card , Aadhar_Card , Religion , Business_Job , 
                  Married_Unmarried ,  No_Of_Members , Joining_Date ,Leaving_Date 
    from     dbo.Ex_Primary_Member 
    where   Flat = @intFlatNum
       and     Joining_Date = @daJoiningDate
       and     Leaving_Date = @daLeavingDate
End

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It'll be more secure (look up "SQL Code Injection") and also you'll be able to test it very easily with all sorts of edge cases (e.g. null for all three input parameters!) before you attach it to your front-end code. This should make it much easier for you to see where your problem is.

hth

Mike

Jacques Bourgeois (James Burger)

It might not be that the data is not displayed, it can simply be that there is no data. First thing is to make sure that you are retrieving something.

Check the DataReader HasRows property is True. If not, then the problem is with your SQL. Try what was suggested by previous experts.