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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 18:07:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 18:07:14 +0000 |
commit | a175314c3e5827eb193872241446f2f8f5c9d33c (patch) | |
tree | cd3d60ca99ae00829c52a6ca79150a5b6e62528b /sql/derived_handler.cc | |
parent | Initial commit. (diff) | |
download | mariadb-10.5-upstream.tar.xz mariadb-10.5-upstream.zip |
Adding upstream version 1:10.5.12.upstream/1%10.5.12upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'sql/derived_handler.cc')
-rw-r--r-- | sql/derived_handler.cc | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/sql/derived_handler.cc b/sql/derived_handler.cc new file mode 100644 index 00000000..f48b95cb --- /dev/null +++ b/sql/derived_handler.cc @@ -0,0 +1,125 @@ +/* + Copyright (c) 2018, 2019 MariaDB + + 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 Street, Fifth Floor, Boston, MA 02111-1301 USA */ + +#include "mariadb.h" +#include "sql_priv.h" +#include "sql_select.h" +#include "derived_handler.h" + + +/** + The methods of the Pushdown_derived class. + + The objects of this class are used for pushdown of the derived tables + into engines. The main method of the class is Pushdown_derived::execute() + that initiates execution of the query specifying a derived by a foreign + engine, receives the rows of the result set and put them in a temporary + table on the server side. + + The method uses only the functions of the derived_handle interface to do + this. The constructor of the class gets this interface as a parameter. + + Currently a derived tables pushed into an engine is always materialized. + It could be changed if the cases when the tables is used as driving table. +*/ + + +Pushdown_derived::Pushdown_derived(TABLE_LIST *tbl, derived_handler *h) + : derived(tbl), handler(h) +{ + is_analyze= handler->thd->lex->analyze_stmt; +} + + +Pushdown_derived::~Pushdown_derived() +{ + delete handler; +} + + +int Pushdown_derived::execute() +{ + int err; + THD *thd= handler->thd; + TABLE *table= handler->table; + TMP_TABLE_PARAM *tmp_table_param= handler->tmp_table_param; + + DBUG_ENTER("Pushdown_query::execute"); + + if ((err= handler->init_scan())) + goto error; + + if (is_analyze) + { + handler->end_scan(); + DBUG_RETURN(0); + } + + while (!(err= handler->next_row())) + { + if (unlikely(thd->check_killed())) + { + handler->end_scan(); + DBUG_RETURN(-1); + } + + if ((err= table->file->ha_write_tmp_row(table->record[0]))) + { + bool is_duplicate; + if (likely(!table->file->is_fatal_error(err, HA_CHECK_DUP))) + continue; // Distinct elimination + + if (create_internal_tmp_table_from_heap(thd, table, + tmp_table_param->start_recinfo, + &tmp_table_param->recinfo, + err, 1, &is_duplicate)) + DBUG_RETURN(1); + if (is_duplicate) + continue; + } + } + + if (err != 0 && err != HA_ERR_END_OF_FILE) + goto error; + + if ((err= handler->end_scan())) + goto error_2; + + DBUG_RETURN(0); + +error: + handler->end_scan(); +error_2: + handler->print_error(err, MYF(0)); + DBUG_RETURN(-1); // Error not sent to client +} + + +void derived_handler::print_error(int error, myf errflag) +{ + my_error(ER_GET_ERRNO, MYF(0), error, hton_name(ht)->str); +} + + +void derived_handler::set_derived(TABLE_LIST *tbl) +{ + derived= tbl; + table= tbl->table; + unit= tbl->derived; + select= unit->first_select(); + tmp_table_param= ((select_unit *)(unit->result))->get_tmp_table_param(); +} + |