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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.h | |
parent | Initial commit. (diff) | |
download | mariadb-10.5-a175314c3e5827eb193872241446f2f8f5c9d33c.tar.xz mariadb-10.5-a175314c3e5827eb193872241446f2f8f5c9d33c.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 '')
-rw-r--r-- | sql/derived_handler.h | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/sql/derived_handler.h b/sql/derived_handler.h new file mode 100644 index 00000000..171165bb --- /dev/null +++ b/sql/derived_handler.h @@ -0,0 +1,85 @@ +/* + Copyright (c) 2016, 2017 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 St, Fifth Floor, Boston, MA 02110-1301 USA */ + +#ifndef DERIVED_HANDLER_INCLUDED +#define DERIVED_HANDLER_INCLUDED + +#include "mariadb.h" +#include "sql_priv.h" + +class TMP_TABLE_PARAM; + +typedef class st_select_lex_unit SELECT_LEX_UNIT; + +/** + @class derived_handler + + This interface class is to be used for execution of queries that specify + derived table by foreign engines +*/ + +class derived_handler +{ +public: + THD *thd; + handlerton *ht; + + TABLE_LIST *derived; + + /* + Temporary table where all results should be stored in record[0] + The table has a field for every item from the select list of + the specification of derived. + */ + TABLE *table; + + /* The parameters if the temporary table used at its creation */ + TMP_TABLE_PARAM *tmp_table_param; + + SELECT_LEX_UNIT *unit; // Specifies the derived table + + SELECT_LEX *select; // The first select of the specification + + derived_handler(THD *thd_arg, handlerton *ht_arg) + : thd(thd_arg), ht(ht_arg), derived(0),table(0), tmp_table_param(0), + unit(0), select(0) {} + virtual ~derived_handler() {} + + /* + Functions to scan data. All these returns 0 if ok, error code in case + of error + */ + + /* Initialize the process of producing rows of the derived table */ + virtual int init_scan()= 0; + + /* + Put the next produced row of the derived in table->record[0] and return 0. + Return HA_ERR_END_OF_FILE if there are no more rows, return other error + number in case of fatal error. + */ + virtual int next_row()= 0; + + /* End prodicing rows */ + virtual int end_scan()=0; + + /* Report errors */ + virtual void print_error(int error, myf errflag); + + void set_derived(TABLE_LIST *tbl); +}; + +#endif /* DERIVED_HANDLER_INCLUDED */ |