#ifndef SQL_TYPE_JSON_INCLUDED
#define SQL_TYPE_JSON_INCLUDED
/*
Copyright (c) 2019, 2021 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
*/
#include "mariadb.h"
#include "sql_type.h"
class Type_handler_json_common
{
public:
static Virtual_column_info *make_json_valid_expr(THD *thd,
const LEX_CSTRING *field_name);
static bool make_json_valid_expr_if_needed(THD *thd, Column_definition *c);
static bool set_format_name(Send_field_extended_metadata *to)
{
static const Lex_cstring fmt(STRING_WITH_LEN("json"));
return to->set_format_name(fmt);
}
static const Type_handler *json_type_handler(uint max_octet_length);
static const Type_handler *json_blob_type_handler_by_length_bytes(uint len);
static const Type_handler *json_type_handler_sum(const Item_sum *sum);
static const Type_handler *json_type_handler_from_generic(const Type_handler *th);
static bool has_json_valid_constraint(const Field *field);
static const Type_collection *type_collection();
static bool is_json_type_handler(const Type_handler *handler)
{
return handler->type_collection() == type_collection();
}
};
template <class BASE, const Named_type_handler<BASE> &thbase>
class Type_handler_general_purpose_string_to_json:
public BASE,
public Type_handler_json_common
{
public:
const Type_handler *type_handler_base() const override
{
return &thbase;
}
const Type_collection *type_collection() const override
{
return Type_handler_json_common::type_collection();
}
bool Column_definition_validate_check_constraint(THD *thd,
Column_definition *c)
const override
{
return make_json_valid_expr_if_needed(thd, c) ||
BASE::Column_definition_validate_check_constraint(thd, c);
}
bool Column_definition_data_type_info_image(Binary_string *to,
const Column_definition &def)
const override
{
/*
Override the inherited method to avoid JSON type handlers writing any
extended metadata to FRM. JSON type handlers are currently detected
only by CHECK(JSON_VALID()) constraint. This may change in the future
to do write extended metadata to FRM, for more reliable detection.
*/
return false;
}
bool Item_append_extended_type_info(Send_field_extended_metadata *to,
const Item *item) const override
{
return set_format_name(to); // Send "format=json" in the protocol
}
bool Item_hybrid_func_fix_attributes(THD *thd,
const LEX_CSTRING &name,
Type_handler_hybrid_field_type *hybrid,
Type_all_attributes *attr,
Item **items, uint nitems)
const override
{
if (BASE::Item_hybrid_func_fix_attributes(thd, name, hybrid, attr,
items, nitems))
return true;
/*
The above call can change the type handler on "hybrid", e.g.
choose a proper BLOB type handler according to the calculated max_length.
Convert general purpose string type handler to its JSON counterpart.
This makes hybrid functions preserve JSON data types, e.g.:
COALESCE(json_expr1, json_expr2) -> JSON
*/
hybrid->set_handler(json_type_handler_from_generic(hybrid->type_handler()));
return false;
}
};
class Type_handler_string_json:
public Type_handler_general_purpose_string_to_json<Type_handler_string,
type_handler_string>
{ };
class Type_handler_varchar_json:
public Type_handler_general_purpose_string_to_json<Type_handler_varchar,
type_handler_varchar>
{ };
class Type_handler_tiny_blob_json:
public Type_handler_general_purpose_string_to_json<Type_handler_tiny_blob,
type_handler_tiny_blob>
{ };
class Type_handler_blob_json:
public Type_handler_general_purpose_string_to_json<Type_handler_blob,
type_handler_blob>
{ };
class Type_handler_medium_blob_json:
public Type_handler_general_purpose_string_to_json<Type_handler_medium_blob,
type_handler_medium_blob>
{ };
class Type_handler_long_blob_json:
public Type_handler_general_purpose_string_to_json<Type_handler_long_blob,
type_handler_long_blob>
{ };
extern MYSQL_PLUGIN_IMPORT
Named_type_handler<Type_handler_string_json> type_handler_string_json;
extern MYSQL_PLUGIN_IMPORT
Named_type_handler<Type_handler_varchar_json> type_handler_varchar_json;
extern MYSQL_PLUGIN_IMPORT
Named_type_handler<Type_handler_tiny_blob_json> type_handler_tiny_blob_json;
extern MYSQL_PLUGIN_IMPORT
Named_type_handler<Type_handler_blob_json> type_handler_blob_json;
extern MYSQL_PLUGIN_IMPORT
Named_type_handler<Type_handler_medium_blob_json> type_handler_medium_blob_json;
extern MYSQL_PLUGIN_IMPORT
Named_type_handler<Type_handler_long_blob_json> type_handler_long_blob_json;
#endif // SQL_TYPE_JSON_INCLUDED
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