Drizzled Public API Documentation

replace_select.cc
1 /* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
2  * vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
3  *
4  * Copyright (C) 2009 Sun Microsystems, Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include <config.h>
22 #include <drizzled/show.h>
23 #include <drizzled/lock.h>
24 #include <drizzled/session.h>
25 #include <drizzled/statement/replace_select.h>
26 #include <drizzled/select_insert.h>
27 #include <drizzled/sql_lex.h>
28 #include <drizzled/open_tables_state.h>
29 
30 namespace drizzled {
31 
33 {
34  TableList *first_table= (TableList *) lex().select_lex.table_list.first;
35  TableList *all_tables= lex().query_tables;
36  assert(first_table == all_tables && first_table != 0);
37  Select_Lex *select_lex= &lex().select_lex;
38 
39  if (insert_precheck(&session(), all_tables))
40  {
41  return true;
42  }
43 
44  /* Don't unlock tables until command is written to binary log */
45  select_lex->options|= SELECT_NO_UNLOCK;
46 
47  lex().unit.set_limit(select_lex);
48 
49  if (session().wait_if_global_read_lock(false, true))
50  {
51  return true;
52  }
53 
54  bool res;
55  if (! (res= session().openTablesLock(all_tables)))
56  {
57  /* Skip first table, which is the table we are inserting in */
58  TableList *second_table= first_table->next_local;
59  select_lex->table_list.first= (unsigned char*) second_table;
60  select_lex->context.table_list= select_lex->context.first_name_resolution_table= second_table;
61  res= insert_select_prepare(&session());
62  if (not res)
63  {
64  select_insert sel_result(first_table, first_table->table, &lex().field_list, &lex().update_list,&lex().value_list, lex().duplicates, lex().ignore);
65  res= handle_select(&session(), &lex(), &sel_result, OPTION_SETUP_TABLES_DONE);
66  /*
67  Invalidate the table in the query cache if something changed
68  after unlocking when changes become visible.
69  TODO: this is a workaround. right way will be move invalidating in
70  the unlock procedure.
71  */
72  if (first_table->lock_type == TL_WRITE_CONCURRENT_INSERT && session().open_tables.lock)
73  {
74  /* INSERT ... SELECT should invalidate only the very first table */
75  TableList *save_table= first_table->next_local;
76  first_table->next_local= 0;
77  first_table->next_local= save_table;
78  }
79  }
80  /* revert changes for SP */
81  select_lex->table_list.first= (unsigned char*) first_table;
82  }
83 
84  /*
85  Release the protection against the global read lock and wake
86  everyone, who might want to set a global read lock.
87  */
88  session().startWaitingGlobalReadLock();
89 
90  return res;
91 }
92 
93 } /* namespace drizzled */
94