private object ExecuteScalarInternal(bool needCLStype, bool needRowid, out OciRowidDescriptor rowidDescriptor)
{
OciStatementHandle statementHandle = null;
object oracleValue = null;
int rc = 0;
try
{
statementHandle = this.GetStatementHandle();
ArrayList resultParameterOrdinals = new ArrayList();
this.Execute(statementHandle, CommandBehavior.Default, needRowid, out rowidDescriptor, out resultParameterOrdinals);
if (OCI.STMT.OCI_STMT_SELECT != this._statementType)
{
return(oracleValue);
}
OracleColumn column = new OracleColumn(statementHandle, 0, this.ErrorHandle, this._connection);
int offset = 0;
bool success = false;
bool mustRelease = false;
SafeHandle handleToBind = null;
column.Describe(ref offset, this._connection, this.ErrorHandle);
NativeBuffer_RowBuffer buffer = new NativeBuffer_RowBuffer(offset, 1);
RuntimeHelpers.PrepareConstrainedRegions();
try
{
buffer.DangerousAddRef(ref success);
column.Bind(statementHandle, buffer, this.ErrorHandle, 0);
column.Rebind(this._connection, ref mustRelease, ref handleToBind);
rc = TracedNativeMethods.OCIStmtFetch(statementHandle, this.ErrorHandle, 1, OCI.FETCH.OCI_FETCH_NEXT, OCI.MODE.OCI_DEFAULT);
if (100 != rc)
{
if (rc != 0)
{
this.Connection.CheckError(this.ErrorHandle, rc);
}
if (needCLStype)
{
oracleValue = column.GetValue(buffer);
}
else
{
oracleValue = column.GetOracleValue(buffer);
}
}
}
finally
{
if (mustRelease)
{
handleToBind.DangerousRelease();
}
if (success)
{
buffer.DangerousRelease();
}
}
GC.KeepAlive(column);
}
finally
{
if (statementHandle != null)
{
this.ReleaseStatementHandle(statementHandle);
}
}
return(oracleValue);
}