Slow performance of SqlDataReader

Question

I\'ve query executing ~2 secs in MSSMS (returning 25K of rows)

Same query used in .NET (sqlReader) exetuting few minutes!

I\'ve also tried to execute only re

Answer 1

I would check to see how long the actual retrieval is taking.

for instance:

  Private Sub timeCheck()
    'NOTE: Assuming you have a sqlconnection object named conn

    'Create stopwatch
    Dim sw As New System.Diagnostics.Stopwatch

    'Setup query
    Dim com As New SqlClient.SqlCommand("QUERY GOES HERE", conn)

    sw.Start()

    'Run query
    Dim dr As SqlClient.SqlDataReader = com.ExecuteReader()

    sw.Stop()

    'Check the time
    Dim sql_query_time As String = CStr((sw.ElapsedMilliseconds / 1000)) & " seconds"
  End Sub

This will allow you to see whether the hold-up is in the retrieval, or in the execution of the reader.