mariadb/sql/field_composite.h
Iqbal Hassan cb5070c052 MDEV-34319: DECLARE TYPE .. TABLE OF .. INDEX BY
in stored routines

This patch adds support for associative arrays in stored procedures
for sql_mode=ORACLE.
The syntax follows Oracle's PL/SQL syntax for associative arrays -
TYPE assoc_array_t IS TABLE OF VARCHAR2(100) INDEX BY INTEGER;
or
TYPE assoc_array_t IS TABLE OF record_t INDEX BY VARCHAR2(100);
where record_t is a record type.

The following functions were added for associative arrays:
- COUNT - Retrieve the number of elements within the arra
- EXISTS - Check whether given key exists in the array
- FIRST - Retrieve the first key in the array
- LAST - Retrieve the last key in the array
- PRIOR - Retrieve the key before the given key
- NEXT - Retrieve the key after the given key
- DELETE - Remove the element with the given key or remove all elements
if no key is given

The arrays/elements can be initialized with the following methods:
- Constructor
i.e. array:= assoc_array_t('key1'=>1, 'key2'=>2, 'key3'=>3)
- Assignment
i.e. array(key):= record_t(1, 2)
- SELECT INTO
i.e. SELECT x INTO array(key)

TODOs:
- Nested tables are not supported yet.
i.e. TYPE assoc_array_t IS TABLE OF other_assoc_array_t INDEX BY INTEGER;
- Associative arrays comparisons are not supported yet.
2025-05-13 15:32:35 +08:00

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C++

/*
Copyright (c) 2025, Rakuten Securities
Copyright (c) 2025, MariaDB plc
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 02110-1335 USA
*/
#ifndef FIELD_COMPOSITE_INCLUDED
#define FIELD_COMPOSITE_INCLUDED
#include "field.h"
class Field_composite: public Field_null
{
public:
Field_composite(uchar *ptr_arg, const LEX_CSTRING *field_name_arg)
:Field_null(ptr_arg, 0, Field::NONE, field_name_arg, &my_charset_bin)
{}
en_fieldtype tmp_engine_column_type(bool use_packed_rows) const override
{
DBUG_ASSERT(0);
return Field::tmp_engine_column_type(use_packed_rows);
}
enum_conv_type rpl_conv_type_from(const Conv_source &source,
const Relay_log_info *rli,
const Conv_param &param) const override
{
DBUG_ASSERT(0);
return CONV_TYPE_IMPOSSIBLE;
}
virtual uint rows() const { return 0; }
virtual bool get_key(String *key, bool is_first) { return true; }
virtual bool get_next_key(const String *curr_key, String *next_key)
{
return true;
}
virtual bool get_prior_key(const String *curr_key, String *prior_key)
{
return true;
}
virtual Item_field *element_by_key(THD *thd, String *key) { return NULL; }
virtual Item_field *element_by_key(THD *thd, String *key) const
{
return NULL;
}
virtual Item **element_addr_by_key(THD *thd, String *key) { return NULL; }
virtual bool delete_all_elements() { return true; }
virtual bool delete_element_by_key(String *key) { return true; }
/*
Retrieve the Item representing the element of the composite field.
Note that the item here may not represent a particular element but
it does contain the information about the element type.
Use element_by_key() to retrieve the item representing a particular
element of the composite field.
*/
virtual Item *get_element_item() const { return NULL; }
};
#endif /* FIELD_COMPOSITE_INCLUDED */