Fastest way to move records from an Oracle database into SQL Server
Posted
by user347748
on Stack Overflow
See other posts from Stack Overflow
or by user347748
Published on 2010-05-22T11:03:37Z
Indexed on
2010/05/22
12:00 UTC
Read the original article
Hit count: 165
Ok this is the scenario... I have a table in Oracle that acts like a queue... A VB.net program reads the queue and calls a stored proc in SQL Server that processes and then inserts the message into another SQL Server table and then deletes the record from the oracle table.
We use a DataReader to read the records from Oracle and then call the stored proc for each of the records. The program seems to be a little slow. The stored procedure itself isn't slow. The SP by itself when called in a loop can process about 2000 records in 20 seconds. But when called from the .Net program, the execution time is about 5 records per second. I have seen that most of the time consumed is in calling the stored procedure and waiting for it to return. Is there a better way of doing this?
Here is a snippet of the actual code
Function StartDataXfer() As Boolean
Dim status As Boolean = False
Try
SqlConn.Open()
OraConn.Open()
c.ErrorLog(Now.ToString & "--Going to Get the messages from oracle", 1)
If GetMsgsFromOracle() Then
c.ErrorLog(Now.ToString & "--Got messages from oracle", 1)
If ProcessMessages() Then
c.ErrorLog(Now.ToString & "--Finished Processing all messages in the queue", 0)
status = True
Else
c.ErrorLog(Now.ToString & "--Failed to Process all messages in the queue", 0)
status = False
End If
Else
status = True
End If
StartDataXfer = status
Catch ex As Exception
Finally
SqlConn.Close()
OraConn.Close()
End Try
End Function
Private Function GetMsgsFromOracle() As Boolean
Try
OraDataAdapter = New OleDb.OleDbDataAdapter
OraDataTable = New System.Data.DataTable
OraSelCmd = New OleDb.OleDbCommand
GetMsgsFromOracle = False
With OraSelCmd
.CommandType = CommandType.Text
.Connection = OraConn
.CommandText = GetMsgSql
End With
OraDataAdapter.SelectCommand = OraSelCmd
OraDataAdapter.Fill(OraDataTable)
If OraDataTable.Rows.Count > 0 Then
GetMsgsFromOracle = True
End If
Catch ex As Exception
GetMsgsFromOracle = False
End Try
End Function
Private Function ProcessMessages() As Boolean
Try
ProcessMessages = False
PrepareSQLInsert()
PrepOraDel()
i = 0
Dim Method As Integer
Dim OraDataRow As DataRow
c.ErrorLog(Now.ToString & "--Going to call message sending procedure", 2)
For Each OraDataRow In OraDataTable.Rows
With OraDataRow
Method = GetMethod(.Item(0))
SQLInsCmd.Parameters("RelLifeTime").Value = c.RelLifetime
SQLInsCmd.Parameters("Param1").Value = Nothing
SQLInsCmd.Parameters("ID").Value = GenerateTransactionID() ' Nothing
SQLInsCmd.Parameters("UID").Value = Nothing
SQLInsCmd.Parameters("Param").Value = Nothing
SQLInsCmd.Parameters("Credit").Value = 0
SQLInsCmd.ExecuteNonQuery()
'check the return value
If SQLInsCmd.Parameters("ReturnValue").Value = 1 And SQLInsCmd.Parameters("OutPutParam").Value = 0 Then 'success
'delete the input record from the source table once it is logged
c.ErrorLog(Now.ToString & "--Moved record successfully", 2)
OraDataAdapter.DeleteCommand.Parameters("P(0)").Value = OraDataRow.Item(6)
OraDataAdapter.DeleteCommand.ExecuteNonQuery()
c.ErrorLog(Now.ToString & "--Deleted record successfully", 2)
OraDataAdapter.Update(OraDataTable)
c.ErrorLog(Now.ToString & "--Committed record successfully", 2)
i = i + 1
Else 'failure
c.ErrorLog(Now.ToString & "--Failed to exec: " & c.DestIns & "Status: " & SQLInsCmd.Parameters("OutPutParam").Value & " and TrackId: " & SQLInsCmd.Parameters("TrackID").Value.ToString, 0)
End If
If File.Exists("stop.txt") Then
c.ErrorLog(Now.ToString & "--Stop File Found", 1)
'ProcessMessages = True
'Exit Function
Exit For
End If
End With
Next
OraDataAdapter.Update(OraDataTable)
c.ErrorLog(Now.ToString & "--Updated Oracle Table", 1)
c.ErrorLog(Now.ToString & "--Moved " & i & " records from Oracle to SQL Table", 1)
ProcessMessages = True
Catch ex As Exception
ProcessMessages = False
c.ErrorLog(Now.ToString & "--MoveMsgsToSQL: " & ex.Message, 0)
Finally
OraDataTable.Clear()
OraDataTable.Dispose()
OraDataAdapter.Dispose()
OraDelCmd.Dispose()
OraDelCmd = Nothing
OraSelCmd = Nothing
OraDataTable = Nothing
OraDataAdapter = Nothing
End Try
End Function
Public Function GenerateTransactionID() As Int64
Dim SeqNo As Int64
Dim qry As String
Dim SqlTransCmd As New OleDb.OleDbCommand
qry = " select seqno from StoreSeqNo"
SqlTransCmd.CommandType = CommandType.Text
SqlTransCmd.Connection = SqlConn
SqlTransCmd.CommandText = qry
SeqNo = SqlTransCmd.ExecuteScalar
If SeqNo > 2147483647 Then
qry = "update StoreSeqNo set seqno=1"
SqlTransCmd.CommandText = qry
SqlTransCmd.ExecuteNonQuery()
GenerateTransactionID = 1
Else
qry = "update StoreSeqNo set seqno=" & SeqNo + 1
SqlTransCmd.CommandText = qry
SqlTransCmd.ExecuteNonQuery()
GenerateTransactionID = SeqNo
End If
End Function
Private Function PrepareSQLInsert() As Boolean
'function to prepare the insert statement for the insert into the SQL stmt using
'the sql procedure SMSProcessAndDispatch
Try
Dim dr As DataRow
SQLInsCmd = New OleDb.OleDbCommand
With SQLInsCmd
.CommandType = CommandType.StoredProcedure
.Connection = SqlConn
.CommandText = SQLInsProc
.Parameters.Add("ReturnValue", OleDb.OleDbType.Integer)
.Parameters("ReturnValue").Direction = ParameterDirection.ReturnValue
.Parameters.Add("OutPutParam", OleDb.OleDbType.Integer)
.Parameters("OutPutParam").Direction = ParameterDirection.Output
.Parameters.Add("TrackID", OleDb.OleDbType.VarChar, 70)
.Parameters.Add("RelLifeTime", OleDb.OleDbType.TinyInt)
.Parameters("RelLifeTime").Direction = ParameterDirection.Input
.Parameters.Add("Param1", OleDb.OleDbType.VarChar, 160)
.Parameters("Param1").Direction = ParameterDirection.Input
.Parameters.Add("TransID", OleDb.OleDbType.VarChar, 70)
.Parameters("TransID").Direction = ParameterDirection.Input
.Parameters.Add("UID", OleDb.OleDbType.VarChar, 20)
.Parameters("UID").Direction = ParameterDirection.Input
.Parameters.Add("Param", OleDb.OleDbType.VarChar, 160)
.Parameters("Param").Direction = ParameterDirection.Input
.Parameters.Add("CheckCredit", OleDb.OleDbType.Integer)
.Parameters("CheckCredit").Direction = ParameterDirection.Input
.Prepare()
End With
Catch ex As Exception
c.ErrorLog(Now.ToString & "--PrepareSQLInsert: " & ex.Message)
End Try
End Function
Private Function PrepOraDel() As Boolean
OraDelCmd = New OleDb.OleDbCommand
Try
PrepOraDel = False
With OraDelCmd
.CommandType = CommandType.Text
.Connection = OraConn
.CommandText = DelSrcSQL
.Parameters.Add("P(0)", OleDb.OleDbType.VarChar, 160) 'RowID
.Parameters("P(0)").Direction = ParameterDirection.Input
.Prepare()
End With
OraDataAdapter.DeleteCommand = OraDelCmd
PrepOraDel = True
Catch ex As Exception
PrepOraDel = False
End Try
End Function
WHat i would like to know is, if there is anyway to speed up this program? Any ideas/suggestions would be highly appreciated...
Regardss, Chetan
© Stack Overflow or respective owner