how to count a distinct of item from a database table?

King Umar

count item(exp: number of laptop,pc) from a database (microsoft sql server 2012) and display it in a textbox or richtextbox in a form in(visual studio 2013) vb.net . thank youuuu friendss...

5 Replies

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Jaipal Reddy11y ago

Accepted answer

The following query returns aDistinct count of laptops.

SELECT COUNT(DISTINCT LapTop) AS Count, 
FROM tbl_Laptop

oputput like : 10

To display it in TextBox

SqlCommand cmd = new SqlCommand("SELECT COUNT(DISTINCT LapTop) AS Count, FROM tbl_Laptop", con);
SqlDataAdapter adp = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
adp.Fill(ds);
txtBox.text = ds..Tables[0].Rows[1]["columnName"].ToString();

Upendra Pratap Shahi11y ago
SqlCommand cmd = new SqlCommand("SELECT COUNT(DISTINCT LapTop) AS LaptopCount FROM tbl_Laptop", "your connection varriable");
SqlDataAdapter da= new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
txtCount.Text = ds.Tables[0].Rows[1]["LaptopCount"].ToString();
King Umar11y ago
thanks jaipal , it help me a lott :)
King Umar11y ago
thank you Mr Thava :) I appreciate it a lot
Thavaselvan Palanivel11y ago
use linq,
var dt1 = _datatable.AsEnumerable().Select(p => new
{
_ID = p.Field<string>("ID"),
_Name = p.Field<string>("Name"),
_Paid = p.Field<string>("Paid"),
_Employed = p.Field<string>("Employed")
-----
------
});

var idr2 = (from xx in dt1
where xx._Employed == "Y"
orderby xx._Name
select xx._Name).Distinct();