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/* Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
#ifndef _sql_cursor_h_
#define _sql_cursor_h_
#ifdef USE_PRAGMA_INTERFACE
#pragma interface /* gcc class interface */
#endif
#include "sql_class.h" /* Query_arena */
class JOIN;
/**
@file
Declarations for implementation of server side cursors. Only
read-only non-scrollable cursors are currently implemented.
*/
/**
Server_side_cursor -- an interface for materialized
implementation of cursors. All cursors are self-contained
(created in their own memory root). For that reason they must
be deleted only using a pointer to Server_side_cursor, not to
its base class.
*/
class Server_side_cursor: protected Query_arena
{
protected:
/** Row destination used for fetch */
select_result *result;
public:
Server_side_cursor(MEM_ROOT *mem_root_arg, select_result *result_arg)
:Query_arena(mem_root_arg, STMT_INITIALIZED), result(result_arg)
{}
virtual bool is_open() const= 0;
virtual int open(JOIN *top_level_join)= 0;
virtual void fetch(ulong num_rows)= 0;
virtual void close()= 0;
virtual bool export_structure(THD *thd, Row_definition_list *defs)
{
DBUG_ASSERT(0);
return true;
}
virtual ~Server_side_cursor();
static void *operator new(size_t size, MEM_ROOT *mem_root)
{ return alloc_root(mem_root, size); }
static void operator delete(void *ptr, size_t size);
static void operator delete(void *, MEM_ROOT *){}
};
int mysql_open_cursor(THD *thd, select_result *result,
Server_side_cursor **res);
#endif /* _sql_cusor_h_ */
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