Am I doin this right? SELECT / ExecuteNonQuery statement

I am working on a web service method that will return weather or not a page url is stored in the database but the ExecuteNonQuery keeps returning -1. I was just wondering if i was doing anything wrong or why the ExecuteNonQuery method does not return a value of 1 or more indicating that the pageurl exists in the database? I have tried using the SQLDataReader as well to no effect and I have verified that SELECT statement refers to valid table and field names. Any help or pointers would be appreciated. I'm still kind of a newb when it comes to db programming.

1 <WebMethod()> _
2Public Function IsPageStored(ByVal pageurlAs String)As Boolean
3 If String.IsNullOrEmpty(pageurl)Then Return False
45 Dim connAs New SqlConnection()
6 conn.ConnectionString = ConfigurationManager.ConnectionStrings("dbStoredList").ConnectionString
78Dim cmdAs String9 cmd ="SELECT [" & Constants.SourceFieldName &"] "10 cmd &="FROM [" & Constants.StoredCopyTableName &"] "11 cmd &="WHERE ([" & Constants.SourceFieldName &"] ='@.Source')"12 Dim C As New SqlCommand(cmd, conn)
13 C.Parameters.AddWithValue("@.Source", New SqlTypes.SqlString(pageurl))
14 C.Parameters.Item("@.Source").CompareInfo = SqlTypes.SqlCompareOptions.IgnoreCase
1516 conn.Open()
1718Dim existsAs Boolean =False19 exists = (C.ExecuteNonQuery > 0)
2021 conn.Close()
22 C.Dispose()
23 C =Nothing24 conn.Dispose()
25 conn =Nothing
2627 Return exists
28End Function29

ExecuteNonQuery:Runs theAdomdCommand without returning any results.

For the purpose I understand, you can use ExecuteReader or ExecuteScalar if you required only one column value is return.

I think you have to use. ExecuteScalar.

Please make sure you click the Answer button if this is true answer.

Regards.

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In addition to what the prior person mentioned, if all you want to know is that the record exists then query for a count. SELECT COUNT(primaryKey) FROM tblName WHERE .....<add all your where conditions here>. Then you can use ExecuteScalar - much more efficient.

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<WebMethod()> _
2 Public Function IsPageStored(ByVal pageurlAs String)As Boolean
3 If String.IsNullOrEmpty(pageurl)Then Return False
4
5 Dim connAs New SqlConnection()
6 conn.ConnectionString = ConfigurationManager.ConnectionStrings("dbStoredList").ConnectionString
7
8 Dim cmdAs String

cmd="IF EXISTS("
9 cmd &="SELECT [" & Constants.SourceFieldName &"] "
10 cmd &="FROM [" & Constants.StoredCopyTableName &"] "
11 cmd &="WHERE ([" & Constants.SourceFieldName &"] ='@.Source')"

cmd &= ") SET @.RETVAL=1 ELSE SET @.RETVAL=0"
12 Dim C As New SqlCommand(cmd, conn)
13 C.Parameters.AddWithValue("@.Source", New SqlTypes.SqlString(pageurl))
14 C.Parameters.Item("@.Source").CompareInfo = SqlTypes.SqlCompareOptions.IgnoreCase

c.Parameters.Add("@.RETVAL", SqlDbType.Int).Direction = ParameterDirection.Output

15
16 conn.Open()
17
18 Dim existsAs Boolean =False

c.ExecuteNonQuery
19 exists = c.Parameter("@.RETVAL").Value
20
21 conn.Close()
22 C.Dispose()
23 C =Nothing
24 conn.Dispose()
25 conn =Nothing
26
27 Return exists
28 End Function

Using the EXISTS allows SQL Server to stop retrieving records when it finds the very first record that matches, instead of having to find them all. This also should force SQL Server to optimize it's query plan.

I've also changed the code from the above examples to use an output parameter instead of returning a value as a resultset. This is a more efficient way to return a simple result as well.

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Thanks for the tips every one, they helped me greatly!