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92d2ceac73
The problem was that when JOIN_TAB::remove_duplicates() noticed there can only be one possible row in the output, it adjusted limits but didn't take into account any possible offset. Fixed by not adjusting limit offset when setting one-row-limit.
83 lines
2.4 KiB
C++
83 lines
2.4 KiB
C++
/* Copyright (c) 2019, MariaDB Corporation.
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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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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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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 02110-1335 USA */
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#ifndef INCLUDES_MARIADB_SQL_LIMIT_H
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#define INCLUDES_MARIADB_SQL_LIMIT_H
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/**
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LIMIT/OFFSET parameters for execution.
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*/
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class Select_limit_counters
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{
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ha_rows select_limit_cnt, offset_limit_cnt;
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public:
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Select_limit_counters():
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select_limit_cnt(0), offset_limit_cnt(0)
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{};
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Select_limit_counters(Select_limit_counters &orig):
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select_limit_cnt(orig.select_limit_cnt),
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offset_limit_cnt(orig.offset_limit_cnt)
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{};
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void set_limit(ha_rows limit, ha_rows offset)
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{
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if (limit == 0)
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offset= 0;
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offset_limit_cnt= offset;
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select_limit_cnt= limit;
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if (select_limit_cnt + offset_limit_cnt >=
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select_limit_cnt)
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select_limit_cnt+= offset_limit_cnt;
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else
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select_limit_cnt= HA_POS_ERROR;
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}
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void set_single_row()
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{
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offset_limit_cnt= 0;
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select_limit_cnt= 1;
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}
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/* Send the first row, still honoring offset_limit_cnt */
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void send_first_row()
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{
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/* Guard against overflow */
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if ((select_limit_cnt= offset_limit_cnt +1 ) == 0)
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select_limit_cnt= offset_limit_cnt;
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// with_ties= false; Remove // on merge to 10.6
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}
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bool is_unlimited()
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{ return select_limit_cnt == HA_POS_ERROR; }
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bool is_unrestricted()
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{ return select_limit_cnt == HA_POS_ERROR && offset_limit_cnt == 0; }
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void set_unlimited()
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{ select_limit_cnt= HA_POS_ERROR; offset_limit_cnt= 0; }
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bool check_offset(ha_rows sent)
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{
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return sent < offset_limit_cnt;
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}
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void remove_offset() { offset_limit_cnt= 0; }
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ha_rows get_select_limit()
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{ return select_limit_cnt; }
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ha_rows get_offset_limit()
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{ return offset_limit_cnt; }
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};
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#endif // INCLUDES_MARIADB_SQL_LIMIT_H
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