I have a problem with the SQL SUM function
The error I got:
Index was outside the bounds of the array.
My code:
SQLcmd = New SqlCommand("SELECT SUM(CAST(distance AS Numeric(10, 1))) FROM route WHERE id BETWEEN '" & op.departure_id & "'AND '" & op.arrival_id & "'", SQLCon)
Dim r As SqlDataReader = SQLcmd.ExecuteReader
While r.Read()
distance = r(3).ToString()
End While
The error is on the distance = r(3).ToString()
This query selects a single column - SUM(CAST(distance AS Numeric(10, 1)))
. You should access it with index 0
, not 3
:
While r.Read()
distance = r(0).ToString()
' Use distance somehow...
End While
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