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mariadb/sql/sql_unions.cc
unknown 3a7d827d09 Further work on UNION's
sql/sql_delete.cc:
  Removed some unnecessary stuff
2001-07-13 13:41:40 +03:00

139 lines
3.5 KiB
C++

/* Copyright (C) 2000 MySQL AB
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; either version 2 of the License, or
(at your option) any later version.
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/* UNION of select's */
/* UNION's were introduced by Monty and Sinisa <sinisa@mysql.com> */
#include "mysql_priv.h"
/* Union of selects */
int mysql_union(THD *thd,LEX *lex,uint no_of_selects)
{
SELECT_LEX *sl, *for_order=&lex->select_lex; uint no=0; int res=0;
List<Item> fields; TABLE *table=(TABLE *)NULL; TABLE_LIST *resulting=(TABLE_LIST *)NULL;
for (;for_order->next;for_order=for_order->next);
ORDER *some_order = (ORDER *)for_order->order_list.first;
for (sl=&lex->select_lex;sl;sl=sl->next, no++)
{
TABLE_LIST *tables=(TABLE_LIST*) sl->table_list.first;
if (!no) // First we do CREATE from SELECT
{
select_create *result;
lex->create_info.options=HA_LEX_CREATE_TMP_TABLE;
if ((result=new select_create(tables->db ? tables->db : thd->db,
NULL, &lex->create_info,
lex->create_list,
lex->key_list,
sl->item_list,DUP_IGNORE)))
{
res=mysql_select(thd,tables,sl->item_list,
sl->where,
sl->ftfunc_list,
(ORDER*) NULL,
(ORDER*) sl->group_list.first,
sl->having,
(ORDER*) some_order,
sl->options | thd->options,
result);
if (res)
{
result->abort();
delete result;
return res;
}
table=result->table;
List_iterator<Item> it(*(result->fields));
Item *item;
while ((item= it++))
fields.push_back(item);
delete result;
if (!reopen_table(table)) return 1;
if (!(resulting = (TABLE_LIST *) thd->calloc(sizeof(TABLE_LIST))))
return 1;
resulting->db=tables->db ? tables->db : thd->db;
resulting->real_name=table->real_name;
resulting->name=table->table_name;
resulting->table=table;
}
else
return -1;
}
else // Then we do INSERT from SELECT
{
select_result *result;
if ((result=new select_insert(table, &fields, DUP_IGNORE)))
{
res=mysql_select(thd,tables,sl->item_list,
sl->where,
sl->ftfunc_list,
(ORDER*) some_order,
(ORDER*) sl->group_list.first,
sl->having,
(ORDER*) NULL,
sl->options | thd->options,
result);
delete result;
if (res) return 1;
}
else
return -1;
}
}
select_result *result;
List<Item> item_list;
List<Item_func_match> ftfunc_list;
ftfunc_list.empty();
if (item_list.push_back(new Item_field(NULL,NULL,"*")))
return -1;
if (lex->exchange)
{
if (lex->exchange->dumpfile)
{
if (!(result=new select_dump(lex->exchange)))
return -1;
}
else
{
if (!(result=new select_export(lex->exchange)))
return -1;
}
}
else if (!(result=new select_send()))
return -1;
else
{
res=mysql_select(thd,resulting,item_list,
NULL,
ftfunc_list,
(ORDER*) NULL,
(ORDER*) NULL,
NULL,
(ORDER*) NULL,
thd->options,
result);
if (res)
result->abort();
}
delete result;
return res;
}