I a 开发者_开发技巧function that used a mySQL Data Adapter and inserts a new row.
I want the function to return the value of the auto-incremented column of the updated row.
Please help.
Public Function addRow(ByVal colA as String, ByVal colB as String) As Integer
Dim dbConnection As New MySqlConnection("server=xxx; user id=xxx; password=xxx; database=xxx; pooling=false;")
Dim dbDataAdapter As New MySqlDataAdapter("SELECT * FROM table", dbConnection)
Dim dbDataSet As DataSet = New DataSet
dbDataAdapter.Fill(dbDataSet, "table")
Dim dbNewRow As DataRow = dbDataSet.Tables("table").NewRow
dbNewRow("colA") = colA
dbNewRow("colB") = colB
dbDataSet.Tables("table").Rows.Add(dbNewRow)
dbDataAdapter.InsertCommand = New MySqlCommand("INSERT into table(colA, colB) VALUES (@colA, @colB)", dbConnection)
dbDataAdapter.InsertCommand.Parameters.Add("colA", MySqlDbType.VarChar, 256, "colA")
dbDataAdapter.InsertCommand.Parameters.Add("colB", MySqlDbType.VarChar, 256, "colB")
Dim dbParm As MySqlParameter = dbDataAdapter.InsertCommand.Parameters.Add("@colID", MySqlDbType.Int16, 16, "colID")
dbParm.Direction = ParameterDirection.ReturnValue
dbDataAdapter.Update(dbDataSet, "table")
Return dbDataAdapter.InsertCommand.Parameters("@colID").Value
End Function
The "Return..." line doesn't work and don't know what the correct code would be.
Assuming the insert stored procedure is doing something like
RETURN @@IDENTITY
You will need the equivalent of this:
oDatabase.AddParameter(oDbCommand, "@RETURN_VALUE", System.Data.DbType.Int32, System.Data.ParameterDirection.ReturnValue, "", System.Data.DataRowVersion.Current, null);
...
oDbCommand.ExecuteNonQuery();
returnStatusCode = (int)oDbCommand.Parameters[0].Value;
Try this:
Dim result As Integer = 0
Integer.TryParse(dbDataAdapter.InsertCommand.Parameters("@colID").Value, result)
Return result
I did it myself again.
Public Function addRow(ByVal colA as String, ByVal colB as String) As Integer
Dim dbConnection As New MySqlConnection("server=xxx; user id=xxx; password=xxx; database=xxx; pooling=false;")
Dim dbDataAdapter As New MySqlDataAdapter("SELECT * FROM table where colID = 0", dbConnection)
Dim dbDataSet As DataSet = New DataSet
dbDataAdapter.Fill(dbDataSet, "table")
Dim dbNewRow As DataRow = dbDataSet.Tables("table").NewRow
dbNewRow("colA") = colA
dbNewRow("colB") = colB
dbDataSet.Tables("table").Rows.Add(dbNewRow)
dbDataAdapter.InsertCommand = New MySqlCommand("INSERT into table(colA, colB) VALUES (@colA, @colB); Select * from table where colID = LAST_INSERT_ID()", dbConnection)
dbDataAdapter.InsertCommand.Parameters.Add("colA", MySqlDbType.VarChar, 256, "colA")
dbDataAdapter.InsertCommand.Parameters.Add("colB", MySqlDbType.VarChar, 256, "colB")
dbDataAdapter.Update(dbDataSet, "table")
Return dbDataSet.Tables("table").Rows(0).Item(0)
End Function
Seems all I needed to do was add a Select statement on the end of the Insert statement and use the LAST_INSERT_ID function to just get the last Inserted row. Then just read from that one rows ID and return it.
I am quite disappointed that DataAdapters work this way. I'm sure classic ASP was easier than this! Thanks to all who responded.
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