Not a valid month error (ORA-1843) - Oracle "timestamp" column vs .NET DateTime

[C# Programming]

Not a valid month error (ORA-1843)
More fun with ODP.NET - Tried different format string none worked!! wasted couple of hours!!

My table column is defined as:
CreateDate timestamp default sysdate NOT NULL

This don't work ...
oParam.Value = DateTime.Now;

So I tried many things... no luck

oParam.Value = DateTime.Now.ToString("dd-MMM-yy"); // HH:m:ss
oParam.Value = DateTime.Now.ToString("dd-MM-yy");
oParam.Value = DateTime.Now.ToString("MM-dd-yy");
oParam.Value = DateTime.Now.ToString("MM/dd/yy");
oParam.Value = DateTime.Now.ToString("dd/MM/yy");


Also tried different combinations using MMM, NO LUCK!!

I then Checked db date format via:

select sysdate from dual;

SYSDATE
16-APR-09
1 row selected.


Last trick - use to_date function in my sql statement + string concatenation instead of parameter!!!
select to_date('16-4-09', 'dd-mm-yy') today from dual
Code:

// More special attention for Oracle provider

if (oContext.DefaultDBProvider == DBUtil.DataProvider.OracleODAC || oContext.DefaultDBProvider == DBUtil.DataProvider.OracleProvider)

{
// Resort to string concatenation!! Just for Oracle!!

strSQL_insert = strSQL_insert.Replace(ORACLE_CREATEDATE, "to_date('" + DateTime.Now.ToString("dd-MM-yy") + "', 'dd-MM-yy')");
}
// If NOT oracle (other providers), we can do it the proper way!!
else
{
oParam = oCmd.CreateParameter();
oParam.ParameterName = DBUtil.FixParameterNameForOracle(oContext.DefaultDBProvider, "@CreateDate");
oParam.Direction = ParameterDirection.Input;
oParam.DbType = DbType.DateTime;
oCmd.Parameters.Add(oParam);
}

Any suggestion? I've isolated the one offending parameter but need the right "format" and ora messages is not helpful at all.

REF:
http://forums.oracle.com/forums/thre...hreadID=631236
http://msdn.microsoft.com/en-us/library/8kb3ddd4.aspx

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