TODBCResult.cxx

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// @(#)root/odbc:$Id$
// Author: Sergey Linev   6/02/2006
 
/*************************************************************************
 * Copyright (C) 1995-2006, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/
 
#include "TODBCResult.h"
#include "TODBCRow.h"
 
 
ClassImp(TODBCResult);
 
////////////////////////////////////////////////////////////////////////////////
/// Constructor
 
TODBCResult::TODBCResult(SQLHSTMT stmt)
{
   fHstmt = stmt;
   fFieldCount = 0;
 
   SQLSMALLINT   columnCount;
 
   SQLRETURN retcode = SQLNumResultCols(fHstmt, &columnCount);
 
   if (retcode == SQL_SUCCESS || retcode == SQL_SUCCESS_WITH_INFO)
      fFieldCount = columnCount;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Cleanup ODBC query result.
 
TODBCResult::~TODBCResult()
{
   Close();
}
 
////////////////////////////////////////////////////////////////////////////////
/// Close (cleanup) ODBC result object. Deletes statement
 
void TODBCResult::Close(Option_t *)
{
   SQLFreeHandle(SQL_HANDLE_STMT, fHstmt);
   fHstmt = nullptr;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Get name of specified field.
 
const char *TODBCResult::GetFieldName(Int_t field)
{
   SQLCHAR columnName[1024];
 
   SQLSMALLINT nameLength;
   SQLSMALLINT dataType;
   SQLULEN     columnSize;
   SQLSMALLINT decimalDigits;
   SQLSMALLINT nullable;
 
   SQLRETURN retcode =
      SQLDescribeCol(fHstmt, field+1, columnName, 1024,
                     &nameLength, &dataType,
                     &columnSize, &decimalDigits, &nullable);
 
   if (retcode != SQL_SUCCESS && retcode != SQL_SUCCESS_WITH_INFO) return nullptr;
 
   fNameBuffer = (const char*) columnName;
 
   return fNameBuffer;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Get next query result row. The returned object must be
/// deleted by the user.
 
TSQLRow *TODBCResult::Next()
{
   if (!fHstmt) return nullptr;
 
   SQLRETURN retcode = SQLFetch(fHstmt);
 
   if (retcode == SQL_SUCCESS || retcode == SQL_SUCCESS_WITH_INFO)
       return new TODBCRow(fHstmt, fFieldCount);
 
   return nullptr;
}