Getting "OleDbCommand.Prepare method requires all parameters to have an explicitly set type." error while updating a dataset
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Hi, I am using dataset to update/insert the data in the database. Whenever its about to update the dataset, it gives me the following error: "OleDbCommand.Prepare method requires all parameters to have an explicitly set type." Can somebody please help me with this problem? Here is my code:
using (OleDbConnection conn = new OleDbConnection(ConnectionString))
{
try
{
conn.Open();
OleDbCommand selectCmd = new OleDbCommand("select * from tableA where col1=? and col2=?", conn);
selectCmd.Parameters.AddWithValue("@col1", val1);
selectCmd.Parameters.AddWithValue("@col2", val2);OleDbDataAdapter adapter = new OleDbDataAdapter(selectCmd);
OleDbCommandBuilder builder = new OleDbCommandBuilder(adapter);DataSet selectDS = new DataSet();
adapter.Fill(selectDS, "TableA");DataTable table = selectDS.Tables["TableA"];
DataRow row = null;int mode = 0; //0 = create, 1 = edit
if (table.Rows.Count > 0)
{
row = table.Rows[0];
mode = 1;
}
else
{
row = table.NewRow();
}row["col1"] = val1;
row["col2"] = val2;
row["col3"] = val3;if (mode == 0)
{
table.Rows.Add(row);
}adapter.Update(selectDS, "TableA"); // this is where the problem occurs
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
finally
{
conn.Close();
}
}Thank you, Prateek
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Hi, I am using dataset to update/insert the data in the database. Whenever its about to update the dataset, it gives me the following error: "OleDbCommand.Prepare method requires all parameters to have an explicitly set type." Can somebody please help me with this problem? Here is my code:
using (OleDbConnection conn = new OleDbConnection(ConnectionString))
{
try
{
conn.Open();
OleDbCommand selectCmd = new OleDbCommand("select * from tableA where col1=? and col2=?", conn);
selectCmd.Parameters.AddWithValue("@col1", val1);
selectCmd.Parameters.AddWithValue("@col2", val2);OleDbDataAdapter adapter = new OleDbDataAdapter(selectCmd);
OleDbCommandBuilder builder = new OleDbCommandBuilder(adapter);DataSet selectDS = new DataSet();
adapter.Fill(selectDS, "TableA");DataTable table = selectDS.Tables["TableA"];
DataRow row = null;int mode = 0; //0 = create, 1 = edit
if (table.Rows.Count > 0)
{
row = table.Rows[0];
mode = 1;
}
else
{
row = table.NewRow();
}row["col1"] = val1;
row["col2"] = val2;
row["col3"] = val3;if (mode == 0)
{
table.Rows.Add(row);
}adapter.Update(selectDS, "TableA"); // this is where the problem occurs
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
finally
{
conn.Close();
}
}Thank you, Prateek
Explicitly and fully define each parameter. Personally, I think it is poor practice to allow a DB to infer such information when it is known ahead of time. It is fairly simple and will reflect well on the continued maintenance of your system. And as a bonus it will eliminate errors such as this from your code.
Need custom software developed? I do C# development and consulting all over the United States. A man said to the universe: "Sir I exist!" "However," replied the universe, "The fact has not created in me A sense of obligation." --Stephen Crane
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Explicitly and fully define each parameter. Personally, I think it is poor practice to allow a DB to infer such information when it is known ahead of time. It is fairly simple and will reflect well on the continued maintenance of your system. And as a bonus it will eliminate errors such as this from your code.
Need custom software developed? I do C# development and consulting all over the United States. A man said to the universe: "Sir I exist!" "However," replied the universe, "The fact has not created in me A sense of obligation." --Stephen Crane
Thanks, I'll keep that in mind.
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Hi, I am using dataset to update/insert the data in the database. Whenever its about to update the dataset, it gives me the following error: "OleDbCommand.Prepare method requires all parameters to have an explicitly set type." Can somebody please help me with this problem? Here is my code:
using (OleDbConnection conn = new OleDbConnection(ConnectionString))
{
try
{
conn.Open();
OleDbCommand selectCmd = new OleDbCommand("select * from tableA where col1=? and col2=?", conn);
selectCmd.Parameters.AddWithValue("@col1", val1);
selectCmd.Parameters.AddWithValue("@col2", val2);OleDbDataAdapter adapter = new OleDbDataAdapter(selectCmd);
OleDbCommandBuilder builder = new OleDbCommandBuilder(adapter);DataSet selectDS = new DataSet();
adapter.Fill(selectDS, "TableA");DataTable table = selectDS.Tables["TableA"];
DataRow row = null;int mode = 0; //0 = create, 1 = edit
if (table.Rows.Count > 0)
{
row = table.Rows[0];
mode = 1;
}
else
{
row = table.NewRow();
}row["col1"] = val1;
row["col2"] = val2;
row["col3"] = val3;if (mode == 0)
{
table.Rows.Add(row);
}adapter.Update(selectDS, "TableA"); // this is where the problem occurs
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
finally
{
conn.Close();
}
}Thank you, Prateek
I agree with Ennis that it's a 'bad' practice to let the autogeneration to create the statements. But if you want to use it, there are two conditions you must meet: - you must use command builder when select statement is created - there must be a key column present in the dataset I think it's the later that may be causing problems. Another possible cause may be column names that contain illegal characters or reserved words. So you should check if for example UpådateCommand is generated correctly. More info: Generating Commands with CommandBuilders (ADO.NET)[^]
The need to optimize rises from a bad design.My articles[^]