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492.3.13
by Lee
code clean move Item_func_floor, Item_func_length, Item_func_min_max, Item_func_rand, Item_func_round to functions directory |
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/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
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* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
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*
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* Copyright (C) 2008 Sun Microsystems
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; version 2 of the License.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include <drizzled/server_includes.h> |
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#include CSTDINT_H
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#include <drizzled/functions/rand.h> |
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void Item_func_rand::seed_random(Item *arg) |
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{
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/*
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TODO: do not do reinit 'rand' for every execute of PS/SP if
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args[0] is a constant.
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*/
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uint32_t tmp= (uint32_t) arg->val_int(); |
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randominit(rand, (uint32_t) (tmp*0x10001L+55555555L), |
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(uint32_t) (tmp*0x10000001L)); |
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}
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||
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520.1.22
by Brian Aker
Second pass of thd cleanup |
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bool Item_func_rand::fix_fields(Session *session,Item **ref) |
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492.3.13
by Lee
code clean move Item_func_floor, Item_func_length, Item_func_min_max, Item_func_rand, Item_func_round to functions directory |
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{
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520.1.22
by Brian Aker
Second pass of thd cleanup |
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if (Item_real_func::fix_fields(session, ref)) |
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492.3.13
by Lee
code clean move Item_func_floor, Item_func_length, Item_func_min_max, Item_func_rand, Item_func_round to functions directory |
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return true; |
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used_tables_cache|= RAND_TABLE_BIT; |
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if (arg_count) |
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{ // Only use argument once in query |
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/*
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No need to send a Rand log event if seed was given eg: RAND(seed),
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as it will be replicated in the query as such.
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*/
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if (!rand && !(rand= (struct rand_struct*) |
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520.1.22
by Brian Aker
Second pass of thd cleanup |
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session->alloc(sizeof(*rand)))) |
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492.3.13
by Lee
code clean move Item_func_floor, Item_func_length, Item_func_min_max, Item_func_rand, Item_func_round to functions directory |
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return true; |
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if (args[0]->const_item()) |
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seed_random (args[0]); |
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}
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else
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{
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/*
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Save the seed only the first time RAND() is used in the query
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Once events are forwarded rather than recreated,
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the following can be skipped if inside the slave thread
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*/
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520.1.22
by Brian Aker
Second pass of thd cleanup |
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if (!session->rand_used) |
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492.3.13
by Lee
code clean move Item_func_floor, Item_func_length, Item_func_min_max, Item_func_rand, Item_func_round to functions directory |
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{
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520.1.22
by Brian Aker
Second pass of thd cleanup |
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session->rand_used= 1; |
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session->rand_saved_seed1= session->rand.seed1; |
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session->rand_saved_seed2= session->rand.seed2; |
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492.3.13
by Lee
code clean move Item_func_floor, Item_func_length, Item_func_min_max, Item_func_rand, Item_func_round to functions directory |
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}
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520.1.22
by Brian Aker
Second pass of thd cleanup |
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rand= &session->rand; |
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492.3.13
by Lee
code clean move Item_func_floor, Item_func_length, Item_func_min_max, Item_func_rand, Item_func_round to functions directory |
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}
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return false; |
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}
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void Item_func_rand::update_used_tables() |
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{
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Item_real_func::update_used_tables(); |
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used_tables_cache|= RAND_TABLE_BIT; |
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}
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double Item_func_rand::val_real() |
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{
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assert(fixed == 1); |
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if (arg_count && !args[0]->const_item()) |
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seed_random (args[0]); |
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return my_rnd(rand); |
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}
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