Part1:JSON格式的支援

版本終於支援了原生的JSON格式,即將關係型資料庫和文件型NO_SQL資料庫集於一身。本文接下來將對這特性分別就和各自實現的方法異同進行介紹和演示。

Part2:建立相應表結構

[[email protected] ~]# mysql -V

mysql  Ver Distrib , for linux- (x86_64) using  EditLine wrapper

mysql> create database helei;
Query OK, 1 row affected ( sec)
mysql> use helei;
Database changed
mysql> create table helei (id int(10) unsigned NOT NULL,context json default null,primary key(id));
Query OK, 0 rows affected ( sec)
mysql> show create table helei \G
*************************** 1. row ***************************
       Table: helei
Create Table: CREATE TABLE `helei` (
  `id` int(10) unsigned NOT NULL,
  `context` json DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8
1 row in set ( sec)
 

Part3:構造資料&測試

mysql> desc helei;
+---------+------------------+------+-----+---------+-------+
| Field   | Type             | Null | Key | Default | Extra |
+---------+------------------+------+-----+---------+-------+
| id      | int(10) unsigned | NO   | PRI | NULL    |       |
| context | json             | YES  |     | NULL    |       |
+---------+------------------+------+-----+---------+-------+
2 rows in set ( sec)

mysql> insert into helei values(1,'{"name":"賀磊","age":100}'),(2,'{"name":"陳加持","age":30}'),(3,'{"name":"於浩","age":28}');
Query OK, 3 rows affected ( sec)
Records: 3  Duplicates: 0  Warnings: 0

mysql> select * from helei;
+----+----------------------------------+
| id | context                          |
+----+----------------------------------+
|  1 | {"age": 100, "name": "賀磊"}     |
|  2 | {"age": 30, "name": "陳加持"}    |
|  3 | {"age": 28, "name": "於浩"}      |
+----+----------------------------------+
3 rows in set ( sec)


mysql> select id,JSON_EXTRACT(context,'$.name') name,JSON_EXTRACT(context,'$.age') age from helei;
+----+-------------+------+
| id | name        | age  |
+----+-------------+------+
|  1 | "賀磊"      | 100  |
|  2 | "陳加持"    | 30   |
|  3 | "於浩"      | 28   |
+----+-------------+------+
3 rows in set ( sec)
獲取Key-Value

mysql> select id,json_keys(context) from helei;
+----+--------------------+
| id | json_keys(context) |
+----+--------------------+
|  1 | ["age", "name"]    |
|  2 | ["age", "name"]    |
|  3 | ["age", "name"]    |
+----+--------------------+
3 rows in set ( sec)
獲取全部Key

mysql> update helei set context=JSON_INSERT(context,'$.name',"賀磊",'$.address','beijing')where id=1;
Query OK, 1 row affected ( sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> select * from helei;
+----+------------------------------------------------------+
| id | context                                              |
+----+------------------------------------------------------+
|  1 | {"age": 100, "name": "賀磊", "address": "beijing"}   |
|  2 | {"age": 30, "name": "陳加持"}                        |
|  3 | {"age": 28, "name": "於浩"}                          |
+----+------------------------------------------------------+
3 rows in set ( sec)
增加Key-Value

mysql> update helei set context=JSON_SET(context,'$.name',"高窮帥")where id=1;
Query OK, 1 row affected ( sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> select * from helei;
+----+---------------------------------------------------------+
| id | context                                                 |
+----+---------------------------------------------------------+
|  1 | {"age": 100, "name": "高窮帥", "address": "beijing"}    |
|  2 | {"age": 30, "name": "陳加持"}                           |
|  3 | {"age": 28, "name": "於浩"}                             |
+----+---------------------------------------------------------+
3 rows in set ( sec)
變更key-value

mysql> update helei set context=JSON_REMOVE(context,'$.name') where id=1;
Query OK, 1 row affected ( sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> select * from helei;
+----+------------------------------------+
| id | context                            |
+----+------------------------------------+
|  1 | {"age": 100, "address": "beijing"} |
|  2 | {"age": 30, "name": "陳加持"}      |
|  3 | {"age": 28, "name": "於浩"}        |
+----+------------------------------------+
3 rows in set ( sec)
刪除Key-Value
 

JSON格式儲存BLOB的測試

Part1:Dynamic Columns處理方式的異同

①的動態列JSON格式儲存

mysql> insert into helei_blob values(1,'{"name":"賀磊","age":100}'),(2,'{"name":"陳加持","age":30}'),(3,'{"name":"於浩","age":28}');
Query OK, 3 rows affected ( sec)
Records: 3  Duplicates: 0  Warnings: 0
mysql> select * from helei_blob;
+----+-------------------------------+
| id | blob_col                      |
+----+-------------------------------+
|  1 | {"name":"賀磊","age":100}     |
|  2 | {"name":"陳加持","age":30}    |
|  3 | {"name":"於浩","age":28}      |
+----+-------------------------------+
3 rows in set ( sec)
 

②MariaDB的動態列JSON格式儲存

MariaDB [helei]> create table helei (id int(10) unsigned NOT NULL,context json default null,primary key(id));
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'json default null,primary key(id))' at line 1
可以看到MariaDB並不能直接儲存JSON型別。

MariaDB [helei]> show create table helei_blob\G;
*************************** 1. row ***************************
       Table: helei_blob
Create Table: CREATE TABLE `helei_blob` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `blob_col` blob,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8
1 row in set ( sec)
ERROR: No query specified

MariaDB [helei]> insert into helei_blob values(5,column_create('color','blue','size','XL'));
Query OK, 1 row affected ( sec)

MariaDB [helei]> select * from helei_blob;
+----+--------------------------------+
| id | blob_col                       |
+----+--------------------------------+
|  1 | {"name":"賀磊","age":100}      |
|  2 | {"name":"陳加持","age":30}     |
|  3 | {"name":"於浩","age":28}       |
|  5 |  	     3 sizecolor!XL!blue |
+----+--------------------------------+
4 rows in set ( sec)
直接查詢是亂碼需用以下函式查詢

MariaDB [helei]> select id,column_json(blob_col) from helei_blob where id =5;
+----+------------------------------+
| id | column_json(blob_col)        |
+----+------------------------------+
|  5 | {"size":"XL","color":"blue"} |
+----+------------------------------+
1 row in set ( sec)

MariaDB [helei]> select id,column_list(blob_col) from helei_blob where id =5;
+----+-----------------------+
| id | column_list(blob_col) |
+----+-----------------------+
|  5 | `size`,`color`        |
+----+-----------------------+
1 row in set ( sec)
獲取全部Key

MariaDB [helei]> select id,column_get(blob_col,'color' as char) as color from helei_blob where id =5;
+----+-------+
| id | color |
+----+-------+
|  5 | blue  |
+----+-------+
1 row in set ( sec)
獲取Key-Value

MariaDB [helei]> update helei_blob set blob_col=column_add(blob_col,'sex','man') where id=5;
Query OK, 1 row affected ( sec)
Rows matched: 1  Changed: 1  Warnings: 0

MariaDB [helei]> select id,column_json(blob_col) from helei_blob where id=5;
+----+------------------------------------------+
| id | column_json(blob_col)                    |
+----+------------------------------------------+
|  5 | {"sex":"man","size":"XL","color":"blue"} |
+----+------------------------------------------+
1 row in set ( sec)
增加Key-Value

MariaDB [helei]> update helei_blob set blob_col=column_add(blob_col,'color','black') where id=5;
Query OK, 1 row affected ( sec)
Rows matched: 1  Changed: 1  Warnings: 0

MariaDB [helei]> select id,column_json(blob_col) from helei_blob where id=5;
+----+-------------------------------------------+
| id | column_json(blob_col)                     |
+----+-------------------------------------------+
|  5 | {"sex":"man","size":"XL","color":"black"} |
+----+-------------------------------------------+
1 row in set ( sec)
更改Key-Value

MariaDB [helei]> update helei_blob set blob_col=column_delete(blob_col,'sex','man') where id=5;
Query OK, 1 row affected ( sec)
Rows matched: 1  Changed: 1  Warnings: 0

MariaDB [helei]> select id,column_json(blob_col) from helei_blob where id=5;
+----+-------------------------------+
| id | column_json(blob_col)         |
+----+-------------------------------+
|  5 | {"size":"XL","color":"black"} |
+----+-------------------------------+
1 row in set ( sec)
刪除Key-Value

——總結——

雖然和/版本對於JSON的支援是比較完整的,不過MongoDB的Sharding功能更加好用,個人更傾向於MongoDB。由於筆者的水平有限，編寫時間也很倉促，文中難免會出現一些錯誤或者不準確的地方，不妥之處懇請讀者批評指正。